UBC Theses and Dissertations

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UBC Theses and Dissertations

Acting upon versus telling about false-beliefs : a comparison of two procedures for accessing young children's… Hala, Suzanne Marie Pauline 1989

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ACTING UPON VERSUS TELLING ABOUT F A L S E - B E L I E F S : A COMPARISON OF TWO PROCEDURES FOR ACCESSING YOUNG CHILDREN'S EARLY THEORIES OF MIND by SUZANNE MARIE PAULINE HALA B.A. ( P s y c h o l o g y ) , U n i v e r s i t y o f V i c t o r i a , 1978 A THESIS SUBMITTED I N PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ARTS, DEVELOPMENTAL PSYCHOLOGY. i n THE FACULTY OF GRADUATE STUDIES D e p a r t m e n t o f P s y c h o l o g y We a c c e p t t h i s t h e s i s as c o n f o r m i n g t o t h e r e q u i r e d s t a n d a r d THE UNIVERSITY OF B R I T I S H COLUMBIA A u g u s t , 1989 © SUZANNE MARIE PAULINE HALA, 1989 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of Psycho logy The University of British Columbia Vancouver, Canada Date August ^ n f DE-6 (2/88) i i ABSTRACT T h i s r e p o r t i s i n t e n d e d t o h e l p a r b i t r a t e t h e u n s e t t l e d m a t t e r o f when i n t h e c o u r s e o f t h e i r e a r l y c o g n i t i v e d e v e l o p m e n t c h i l d r e n f i r s t e v i d e n c e some " t h e o r y - l i k e " u n d e r s t a n d i n g o f t h e i r own a n d o t h e r s ' m e n t a l l i v e s . To t h i s e n d , t h i s s t u d y d i r e c t l y c o m p a r e d r e s u l t s o b t a i n e d t h r o u g h t h e a d m i n i s t r a t i o n o f t w o c o m p e t i n g a s s e s s m e n t p r o c e d u r e s , e a c h o f w h i c h h a s b e e n u s e d t o s u p p o r t c o n f l i c t i n g c l a i m s r e g a r d i n g t h e e a r l i e s t age a t w h i c h c h i l d r e n f i r s t e v i d e n c e a n u n d e r s t a n d i n g o f t h e p o s s i b i l i t y o f f a l s e b e l i e f s . A s u b s t a n t i a l b o d y o f r e c e n t r e s e a r c h h a s c o n t r i b u t e d t o a g r o w i n g , b u t p e r h a p s p r e m a t u r e c o n s e n s u s t h a t c h i l d r e n u n d e r 4 y e a r s o f age do n o t r e c o g n i z e t h e p o s s i b i l i t y o f c o u n t e r f a c t u a l b e l i e f s i n o t h e r s a n d c o n s e q u e n t l y l a c k a n y e a r l y t h e o r y o f m i n d . Much o f t h e e v i d e n c e i n s u p p o r t o f t h i s l a t e - o n s e t v i e w i s b a s e d u p o n t h e u s e o f a n " u n e x p e c t e d c h a n g e " t a s k d e v e l o p e d b y Wimmer and P e r n e r ( 1 9 8 3 ) i n w h i c h c h i l d r e n a r e a s k e d t o p r e d i c t w here a n i n a d e q u a t e l y i n f o r m e d s t o r y c h a r a c t e r w i l l s e a r c h f o r an o b j e c t . I n c o n t r a s t t o t h e s e f i n d i n g s r e s u l t s o b t a i n e d u s i n g a r e c e n t l y d e v e l o p e d h i d e - a n d - s e e k t a s k , w h i c h d i r e c t l y a s s e s s e d c h i l d r e n ' s a b i l i t i e s t o g e n e r a t e m i s l e a d i n g c l u e s i n o r d e r t o p r o d u c e a f a l s e - b e l i e f i n a n o t h e r , o f f e r e d s t r o n g s u p p o r t f o r a much e a r l i e r - o n s e t p o s i t i o n ( C h a n d l e r , F r i t z & H a l a , i n p r e s s ) . D e s p i t e s t r o n g m e t h o d o l o g i c r e a s o n s i n f a v o u r o f a c c e p t i n g t h e r e s u l t s o f t h i s i n v e s t i g a t i o n t h e p o s s i b i l i t y r e m a i n e d t h a t t h e 3 - y e a r - o l d s i n t h e C h a n d l e r e t a l . s t u d y w e r e a s p e c i a l population that might also have succeeded i n the unexpected change task had they been given i t . To guard against t h i s p o s s i b i l i t y the present study provided a wi thin-subject comparison of both the unexpected change procedure and the newer hide-and-seek procedure based on the responses of 30 c h i l d r e n ages 3.0, 3.5 and 4.0 years. A further t e s t of f a l s e - b e l i e f understanding was provided by asking subjects to comment d i r e c t l y upon t h e i r opponent's b e l i e f based on subjects ' own misleading act ions . As predicted even young 3-year-olds demonstrated the a b i l i t y to provide misleading clues to t h e i r opponent but when faced with the unexpected change task these youngest subjects performed poorly . When responding to the f a l s e - b e l i e f question based on t h e i r own deceptive act ions , however, even these youngest subjects showed strong evidence of understanding the p o s s i b i l i t y of fa l s e b e l i e f s i n others. i v TABLE OF CONTENTS A b s t r a c t i i T a b l e o f C o n t e n t s i v L i s t o f T a b l e s v i L i s t o f F i g u r e s v i i A c k n o w l e d g e m e n t v i i i CHAPTER 1: INTRODUCTION 1 S t a t e m e n t o f t h e P r o b l e m 1 A S y n o p s i s o f C o m p e t i n g V i e w s o f E m e r g i n g T h e o r i e s o f M i n d 1 An A l t e r n a t i v e t o S t a n d a r d F a l s e B e l i e f M e a s u r e s . . . 3 Summary o f H y p o t h e s e s 8 CHAPTER 2: METHOD 9 P r o c e d u r a l Summary 9 S u b j e c t s 9 M a t e r i a l s 10 P r o c e d u r e 10 S c o r i n g 15 U n e x p e c t e d Change T a s k 15 H i d e - a n d - S e e k T a s k 16 CHAPTER 3: RESULTS 21 O r d e r a nd Sex E f f e c t s 22 P a r t I : R e p l i c a t i o n o f t h e C h a n d l e r , F r i t z a n d H a l a s t u d y 22 V P a r t I I : S t a n d a r d U n e x p e c t e d Change M e a s u r e 25 D e c e p t i o n v e r s u s U n e x p e c t e d Change M e a s u r e 28 P a r t I I I : P r e d i c t i n g F a l s e B e l i e f i n t h e D e c e p t i o n T a s k 29 J u s t i f i c a t i o n s 34 CHAPTER 4: DISCUSSION 37 D e t a i l s a n d I m p l i c a t i o n s o f t h e R e s e a r c h F i n d i n g s . . . 37 L i m i t a t i o n s a n d S u g g e s t i o n s f o r F u t u r e R e s e a r c h . . . . 42 REFERENCES 45 TABLES 55 FIGURES 69 APPENDICES 76 A. R e v i e w o f t h e L i t e r a t u r e 77 B. P r o t o c o l f o r U n e x p e c t e d Change T a s k 117 L I S T OF TABLES v i T a b l e 1: H i d i n g S t r a t e g i e s b y Age 56 T a b l e 2: P r e s e n c e o r A b s e n c e o f D e c e p t i v e S t r a t e g y b y Age . 57 T a b l e 3'- P e r f o r m a n c e on I g n o r a n c e Q u e s t i o n i n U n e x p e c t e d Change T a s k b y Age 58 T a b l e 4: P e r f o r m a n c e on F a l s e B e l i e f Q u e s t i o n i n U n e x p e c t e d Change T a s k b y Age 59 T a b l e 5: I g n o r a n c e b y F a l s e B e l i e f i n U n e x p e c t e d Change T a s k 60 T a b l e 6: W i t h i n S u b j e c t C o m p a r i s o n o f H i d e - a n d - S e e k and U n e x p e c t e d Change T a s k s 61 T a b l e 7: P e r f o r m a n c e on I g n o r a n c e Q u e s t i o n i n H i d e - a n d - S e e k T a s k b y Age 62 T a b l e 8: P e r f o r m a n c e on F a l s e B e l i e f Q u e s t i o n i n H i d e - a n d -S e e k T a s k b y Age 63 T a b l e 9: P r e d i c t e d C e l l s f o r C o n c e p t u a l D e f i c i t H y p o t h e s i s 64 T a b l e 10: P r e d i c t e d C e l l s f o r C o n c e p t u a l C o m p e t e n c e H y p o t h e s i s 65 T a b l e 11: O b s e r v e d F r e q u e n c i e s f o r F a l s e B e l i e f Q u e s t i o n i n H i d e - a n d - S e e k T a s k 66 T a b l e 12: J u s t i f i c a t i o n o f R e s p o n s e s o n U n e x p e c t e d Change T a s k b y Age 67 T a b l e 13: J u s t i f i c a t i o n o f R e s p o n s e s on H i d e - a n d - S e e k T a s k b y Age 68 L I S T OF FIGURES v i i F i g u r e 1: E x p e r i m e n t a l S e t u p f o r U n e x p e c t e d Change P r o c e d u r e 70 F i g u r e 2: E x p e r i m e n t a l S e t u p f o r H i d e - a n d - S e e k P r o c e d u r e . 72 F i g u r e 3: C o m p a r i s o n o f P e r f o r m a n c e B e t w e e n U n e x p e c t e d Change T a s k and H i d e - a n d - S e e k T a s k 74 ACKNOWLEDGEMENTS v i i i On t h i s p a g e I w o u l d l i k e t o t h a n k a l l t h o s e whose h e l p d i r e c t l y c o n t r i b u t e d t o t h e s u c c e s s f u l c o m p l e t i o n o f t h i s p r o j e c t , a n d t h e many o t h e r s whose e n c o u r a g e m e n t a nd s u p p o r t s e r v e d t o g u i d e me t h r o u g h o u t t h i s p r o j e c t . To my s u p e r v i s o r , M i c h a e l C h a n d l e r , I w o u l d l i k e t o e x p r e s s my d e e p a p p r e c i a t i o n f o r t h e g e n e r o u s a n d t h o u g h t f u l i n t e l l e c t u a l g u i d a n c e h e h a s p r o v i d e d n o t o n l y i n t h e c o u r s e o f t h i s p r o j e c t b u t a l s o i n t h e i n t e r e s t s o f my b r o a d e r a c a d e m i c e d u c a t i o n . I w o u l d l i k e t o t h a n k J a n e t W e r k e r , P e t e r G r a f a n d G l e n D i x o n f o r s e r v i n g o n my t h e s i s c o m m i t t e e a n d f o r t h e i r h e l p f u l comments and t h e i r e n t h u s i a s m f o r t h i s r e s e a r c h p r o j e c t . I w o u l d l i k e t o a c k n o w l e d g e t h e c o n t r i b u t i o n s made b y An n a F r i t z a s an i n t e g r a l p a r t o f t h e r e s e a r c h g r o u p o u t o f w h i c h t h e o r i g i n a l m e a s u r e e m e r g e d a n d I w i s h t o t h a n k h e r f o r h e r d i l i g e n t e f f o r t s i n t h e r e l i a b i l i t y s c o r i n g o f t h e d a t a . I w o u l d a l s o l i k e t o t h a n k V a l e r i e L l o y d a n d T r i s h N i e l s e n f o r t h e i r c o n s c i e n t i o u s a s s i s t a n c e w i t h c o l l e c t i n g t h e d a t a f o r t h i s p r o j e c t a s w e l l a s J a n e t W e r k e r who so g e n e r o u s l y made them a v a i l a b l e f o r t h i s p r o j e c t . I w i s h a l s o t o e x t e n d my a p p r e c i a t i o n t o t h e U n i v e r s i t y o f B r i t i s h C o l u m b i a C h i l d S t u d y C e n t r e , w i t h s p e c i a l t h a n k s t o G l e n D i x o n a n d Sue F i s h e r , a n d t o t h e t e a c h e r s , s t a f f , p a r e n t s a n d c h i l d r e n w i t h o u t whose c o o p e r a t i o n a n d p a r t i c i p a t i o n t h i s p r o j e c t c o u l d n o t h a v e b e e n c o m p l e t e d . F i n a l l y , I w i s h t o e x t e n d my d e e p e s t g r a t i t u d e t o J o h n Sampson f o r h i s u n f a i l i n g s u p p o r t a n d h i s g o o d humored c o m p u t e r t u t o r a g e a n d t o Graeme H a l a Sampson a n d I a n H a l a Sampson f o r h e l p i n g me k e e p i t a l l i n p e r s p e c t i v e . CHAPTER 1: INTRODUCTION 1 S t a t e m e n t o f t h e P r o b l e m T h i s t h e s i s i s i n t e n d e d t o h e l p a r b i t r a t e t h e u n s e t t l e d m a t t e r o f when i n t h e c o u r s e o f t h e i r e a r l y c o g n i t i v e d e v e l o p m e n t c h i l d r e n f i r s t e v i d e n c e some t h e o r y - l i k e u n d e r s t a n d i n g o f t h e i r own and o t h e r s ' m e n t a l l i v e s . To t h i s e n d , t h i s s t u d y d i r e c t l y c o m p a r e d t h e r e s u l t s o f two c o m p e t i n g a s s e s s m e n t p r o c e d u r e s , e a c h o f w h i c h h a s b e e n u s e d t o s u p p o r t c o n f l i c t i n g c l a i m s a s t o t h e e a r l i e s t age a t w h i c h c h i l d r e n f i r s t e v i d e n c e a n u n d e r s t a n d i n g o f t h e p o s s i b i l i t y o f f a l s e b e l i e f s . W h i l e t h e r e e x i s t s g e n e r a l a g r e e m e n t among c o n t r i b u t o r s t o t h i s l i t e r a t u r e t h a t y o u n g c h i l d r e n do i n f a c t a c q u i r e some t h e o r y - l i k e k n o w l e d g e o f m e n t a l e v e n t s s o m e t i m e d u r i n g t h e i r p r e -s c h o o l y e a r s ( O l s o n , A s t i n g t o n & H a r r i s , 1 9 8 8 ) , w h a t c o n t i n u e s t o r e m a i n u n s e t t l e d i s j u s t when i n t h e i r e a r l y c o g n i t i v e d e v e l o p m e n t s u c h e v i d e n c e i s f i r s t i n p l a c e . F o r t h e mos t p a r t , a d v o c a t e s o f t h e s e d i v e r g e n t v i e w s c a n de d i v i d e d i n t o one o r t h e o t h e r o f t w o o p p o s i n g camps, one o f w h i c h p r o m o t e s an e a r l y -a n d t h e o t h e r a l a t e - o n s e t v i e w . A S y n o p s i s o f C o m p e t i n g V i e w s o f E m e r g i n g T h e o r i e s o f M i n d A c c o r d i n g t o t h e f i r s t o r e a r l y - o n s e t p o s i t i o n , c h i l d r e n a s y o u n g a s 2 1/2 y e a r s o f age a r e s a i d t o be c a p a b l e o f some p r e l i m i n a r y u n d e r s t a n d i n g o f t h e r o l e o f m e n t a l p r o c e s s e s i n d e t e r m i n i n g t h e i r own and o t h e r ' s a c t i o n s ( e g . C h a n d l e r , F r i t z & H a l a , i n p r e s s ; L e s l i e , 1982; W e l l m a n , 1985, 1988, i n p r e s s ) . By 2 c o n t r a s t , a d v o c a t e s o f t h e d e l a y e d - o n s e t v i e w m a i n t a i n t h a t i t i s n o t u n t i l a r o u n d 4 o r 5 y e a r s o f age t h a t c h i l d r e n f i r s t g i v e e v i d e n c e o f u n d e r s t a n d i n g t h e p o s s i b i l i t y o f f a l s e b e l i e f s a n d , c o n s e q u e n t l y , c a n be s a i d t o h o l d t o some t h e o r y - l i k e u n d e r s t a n d i n g o f m i n d ( e g . G o p n i k &. A s t i n g t o n , 1988; P e r n e r , Leekam, & Wimmer, 1 9 8 7 ) . I n s u p p o r t o f t h e e a r l y - o n s e t p o s i t i o n i n v e s t i g a t o r s s u c h a s B r e t h e r t o n ( 1 9 8 4 ) , f o r e x a m p l e , p o i n t t o t h e f a c t t h a t c h i l d r e n a s y o u n g a s 2 o r 2 1/2 y e a r s o l d s p o n t a n e o u s l y e m p l o y v a r i o u s m e n t a l s t a t e t e r m s i n t h e i r e v e r y d a y s p e e c h . S i m i l a r l y , 2- a n d 3 - y e a r o l d s a l s o show c o n s i d e r a b l e c o m p e t e n c e i n r e p r e s e n t i n g a l t e r n a t i v e m o d e l s o f r e a l i t y a s d e m o n s t r a t e d t h r o u g h t h e i r a b i l i t y t o engage i n a c t s o f p r e t e n d p l a y ( L e s l i e , 1 9 8 8 ) , t h e i r s k i l l i n c o n t r a s t i n g b e l i e f s t a t e s w i t h r e a l i t y ( S h a t z , W e l l m a n & S i l b e r , 1 9 8 3 ) , t h e i r s p o n t a n e o u s t e n d e n c y t o i n v o k e f a l s e b e l i e f s i n a c c o u n t i n g f o r a n o m a l o u s b e h a v i o u r s ( W e l l m a n , i n p r e s s ) a n d t h e i r a b i l i t i e s t o u n d e r s t a n d t h e d i f f e r e n c e b e t w e e n r e a l a n d i m a g i n a r y o b j e c t s , a l l o f w h i c h s u p p o r t t h e n o t i o n t h a t y o u n g c h i l d r e n a l r e a d y p o s s e s s some b a s i c t h e o r y o f m i n d . I n c o n t r a s t t o t h i s e a r l y o n s e t p o s i t i o n , o t h e r s h a v e h e l d o u t f o r w h a t i s a r g u e d t o b e a more e x a c t i n g s t a n d a r d o f e v i d e n c e . A c c o r d i n g t o t h i s v i e w , e v i d e n c e o f a n y t h e o r y o f m i n d i s s a i d t o r e q u i r e t h e a b i l i t y t o r e c o g n i z e t h a t o t h e r s w i l l a c t upon t h e i r b e l i e f s e v e n when t h e s e b e l i e f s a r e o b j e c t i v e l y f a l s e . A d v o c a t e s o f t h i s p r e s u m a b l y t o u g h e r m i n d e d p o s i t i o n h a v e r e g u l a r l y r e p o r t e d a s u b s t a n t i a l l y l a t e r o n s e t t i m e f o r 3 c h i l d r e n ' s f i r s t t h e o r i e s of mind. Using an ingenious but complicated measurement paradigm, Wimmer and Perner (1983) and t h e i r c o l l e a g u e s , f o r example, have presented evidence s a i d t o e s t a b l i s h t h a t c h i l d r e n younger than approximately 4 years of age e n t i r e l y l a c k any demonstrable t h e o r y of mind. The "unexpected change" procedure promoted by these authors has s i n c e become a wid e l y accepted l i t m u s t e s t of young c h i l d r e n ' s understanding of f a l s e b e l i e f and, consequently, t h e i r f i r s t t h e o r i e s of mind. In t h i s procedure s u b j e c t s are t o l d a s t o r y w h i l e i t i s acted out wit h two d o l l f i g u r e s , both of which i n i t i a l l y have equal access t o i n f o r m a t i o n about the t r u e l o c a t i o n of an o b j e c t . One d o l l then l e a v e s the room and i n i t s absence, the o b j e c t i s moved ( i . e . , i t s l o c a t i o n i s unexpectedly changed) t o a second l o c a t i o n . S u b j e c t s are then r e q u i r e d t o p r e d i c t where they t h i n k t h i s i l l informed d o l l w i l l s e a r c h f o r the concealed o b j e c t . A subsequent s e r i e s of minor m o d i f i c a t i o n s and s i m p l i f i c a t i o n s i n t h i s procedure (e.g. Gopnik & A s t i n g t o n , 1988; Hogrefe, Wimmer & Perner, 1986; Perner, Leekam & Wimmer 1987; Wimmer, Gruber & Perner, 1984, 1985) have so f a r done n o t h i n g t o s u b s t a n t i a l l y a l t e r the o r i g i n a l f i n d i n g t h a t c h i l d r e n r e g u l a r l y f a i l t h i s measure u n t i l they are approximately 4 years o l d ( f o r a p o s s i b l e e x c e p t i o n t o t h i s g e n e r a l i z a t i o n see Lewis, i n p r e p a r a t i o n ) . An A l t e r n a t i v e t o Standard F a l s e B e l i e f Measures In a r e c e n t attempt t o a r b i t r a t e between the e a r l y and l a t e onset views Chandler, F r i t z and Hala ( i n p r e s s ) i n t r o d u c e d a 4 n o v e l m e a s u r e m e n t s t r a t e g y t h a t u t i l i z e d a t e s t o f c h i l d r e n ' s a b i l i t i e s t o d e c e i v e o t h e r s a s a m e thod o f i n d e x i n g t h e i r u n d e r s t a n d i n g o f f a l s e b e l i e f s . I n t h i s s t u d y c h i l d r e n b e t w e e n t h e a g e s o f 2 1/2 and 5 y e a r s t o o k p a r t i n a h i d e - a n d - s e e k game i n w h i c h t h e y w e r e a s k e d t o h i d e a " t r e a s u r e " f r o m a s e c o n d e x p e r i m e n t e r . C o m p l i c a t i n g t h i s t a s k was t h e f a c t t h a t s u b j e c t s w e r e r e q u i r e d t o c o m p l e t e t h i s h i d i n g o p e r a t i o n u s i n g a d o l l w h i c h l e f t a c l e a r t r a i l o f f o o t p r i n t s t h a t i m m e d i a t e l y g a v e away i t s movements on t h e p l a y i n g s u r f a c e . The t a s k c o n f r o n t i n g t h e s u b j e c t was how t o h i d e t h e t r e a s u r e g i v e n t h e p r e s e n c e o f t e l l -t a l e t r a c k s i n d i c a t i n g t h e i r c h o s e n h i d i n g l o c a t i o n . The m e a s u r e e x t r a c t e d f r o m t h i s p r o c e d u r e c o n c e r n e d t h e a b i l i t y o f s u b j e c t s t o t a k e a c t i v e s t e p s t o " d i s i n f o r m " t h e i r o p p o n e n t . On t h e a s s u m p t i o n t h a t o n l y s u b j e c t s who u n d e r s t o o d t h e p o s s i b i l i t y o f f a l s e b e l i e f c o u l d u n d e r t a k e t o d i s i n f o r m o t h e r s , c l e a r e v i d e n c e o f s u c h d e c e i t was t a k e n as a d e m o n s t r a t i o n o f some a l r e a d y p r e s e n t t h e o r y o f m i n d . W i t h t h e a i d o f t h i s l e s s p a s s i v e , l e s s h y p o t h e t i c a l a n d l e s s v e r b a l l y e n c u m b e r e d a s s e s s m e n t s t r a t e g y C h a n d l e r e t a l . ( i n p r e s s ) d e m o n s t r a t e d t h a t when o p e r a t i n g o n t h e i r own b e h a l f c h i l d r e n a s y o u n g a s 2 1/2 y e a r s o f age d i d engage i n a c t s o f p u r p o s e f u l d e c e i t , t h u s d e m o n s t r a t i n g a w o r k i n g u n d e r s t a n d i n g o f t h e p o s s i b i l i t y o f f a l s e b e l i e f . A l o n g l i s t o f p o t e n t i a l r e a s o n s e x i s t a s t o why t h e s e two f a l s e - b e l i e f m e a s u r e s may h a v e g e n e r a t e d s u c h d i f f e r e n t r e s u l t s . As a l r e a d y a l l u d e d t o a b o v e , Wimmer an d P e r n e r ' s u n e x p e c t e d c h a n g e m e a s u r e i n v o l v e s s u b j e c t s a s t h i r d p a r t y b y s t a n d e r s who 5 p a s s i v e l y o b s e r v e t h e u n f o l d i n g o f a l o n g a n d h y p o t h e t i c a l n a r r a t i v e a b o u t a s e q u e n c e o f e v e n t s i n w h i c h t h e y h a v e no p e r s o n a l s t a k e . They a r e a l s o r e q u i r e d t o p r o c e s s a n d remember t h e s p e c i f i c i n f o r m a t i o n a l d e t a i l s made a v a i l a b l e t o t h e m s e l v e s and t h e v a r i o u s s t o r y c h a r a c t e r s a n d c o n s e q u e n t l y i n f e r e x a c t l y what b e l i e f s e a c h i s l e g i t i m a t e l y e n t i t l e d t o . The p o s s i b i l i t y a l s o e x i s t s t h a t t h e r e l a t i v e l y p o o r s h o w i n g o f y o u n g s u b j e c t s on t h e u n e x p e c t e d c h a n g e m e a s u r e i s i n p a r t t r a c e a b l e t o t h e f a c t t h a t t h i s a n d s i m i l a r l y s t r u c t u r e d m e a s u r e s r e q u i r e , n o t o n l y t h e a b i l i t y t o c o n s i d e r t h e p o s s i b i l i t y o f f a l s e b e l i e f s , b u t a l s o t h o s e a d d i t i o n a l e x p o s i t o r y s k i l l s n e c e s s a r y t o t e l l a b o u t o r comment upon s u c h a n u n d e r s t a n d i n g . F i n a l l y , b e c a u s e b o t h m e a s u r e s were n o t a d m i n i s t e r e d t o t h e same s a m p l e , t h e p o s s i b i l i t y r e m a i n s o pen t h a t t h e s u b j e c t s o f t h e C h a n d l e r e t a l . s t u d y somehow c o n s t i t u t e d a n u n u s u a l l y p r e c o c i o u s s a m p l e , who a l s o m i g h t h a v e p a s s e d t h e W i m m e r - P e r n e r u n e x p e c t e d c h a n g e m e a s u r e h a d t h e y b e e n g i v e n t h e o p p o r t u n i t y . The p r e s e n t s t u d y p u t t h i s l a s t p o s s i b i l i t y t o t h e t e s t b y p r o v i d i n g a d i r e c t w i t h i n - s u b j e c t c o m p a r i s o n o f t h e two meas u r e m e n t p a r a d i g m s . To t h i s e n d s u b j e c t s r a n g i n g i n age f r o m 3.0 t o 4.5 y e a r s w e r e t e s t e d u s i n g b o t h o f t h e s e e x p e r i m e n t a l p r o c e d u r e s . On t h e s t r e n g t h o f t h e a s s u m p t i o n t h a t y o u n g 3 - y e a r - o l d s do i n f a c t u n d e r s t a n d t h e p o s s i b i l i t y o f f a l s e b e l i e f s , b u t c o n t i n u e t o f a i l u n e x p e c t e d c h a n g e m e a s u r e s f o r r e a s o n s h a v i n g t o do w i t h t h e i r u n n e c e s s a r y p r o c e d u r a l c o m p l e x i t y i t was h y p o t h e s i z e d t h a t e v e n t h e y o u n g e s t s u b j e c t s o f t h e p r e s e n t s t u d y w o u l d s u c c e e d on t h e 6 d e c e p t i o n m e a s u r e b u t s t i l l f a i l t h e u n e x p e c t e d c h a n g e t a s k . A s e c o n d a nd c o n c e p t u a l l y more w e i g h t y c o u n t e r e x p l a n a t i o n f o r t h e d i v e r g e n t r e s u l t s p r o d u c e d b y d e c e p t i o n a n d u n e x p e c t e d c h a n g e m e a s u r e s c o n c e r n s t h e p r o s p e c t t h a t t h e s u b j e c t s o f t h e C h a n d l e r , F r i t z a n d H a l a s t u d y , w h i l e somehow a b l e t o m a n i p u l a t e t h e b e h a v i o u r o f t h e i r o p p o n e n t i n t h e h i d e - a n d - s e e k t a s k , d i d n o t u n d e r t a k e t h e v a r i o u s d i s i n f o r m i n g s t r a t e g i e s t h a t t h e y e m p l o y e d w i t h any i n t e n t o f a c t u a l l y m a n i p u l a t i n g t h e o t h e r ' s b e l i e f s . I n s t e a d , i t m i g h t be a r g u e d , t h e y o u n g s u b j e c t s i n t h e C h a n d l e r e t a l . s t u d y w e r e a t t e m p t i n g s i m p l y t o l e a d o t h e r s i n t o w r o n g b e h a v i o r a l c h o i c e s , w i t h o u t a n y s e r i o u s k n o w l e d g e o f o r i n t e r e s t i n t h e i r p o t e n t i a l f o r h o l d i n g t o f a l s e b e l i e f s . One e x p l i c i t t e s t o f t h i s r e d u c t i v e i n t e r p r e t a t i o n i s t o w a i t u n t i l s u b j e c t s h a d c o m p l e t e d t h e i r a t t e m p t t o h i d e t h e t r e a s u r e a n d t h e n a s k them d i r e c t l y a b o u t w h a t t h e y t h o u g h t t h e i r o p p o n e n t w o u l d b e l i e v e a b o u t t h e l o c a t i o n o f t h e t r e a s u r e a n d w h e r e he o r sh e c o u l d be e x p e c t e d t o b e g i n t h e i r s e a r c h . R e s p o n s e s o n t h e p a r t o f t h e s u b j e c t s i n d i c a t i n g t h a t t h e y e x p e c t e d t h e i r o p p o n e n t t o be t a k e n i n b y t h e i r d e c e p t i v e e f f o r t s a n d t o s e a r c h i n a f a l s e l o c a t i o n w o u l d i n d i c a t e t h a t t h e y u n d e r s t a n d a nd c a n g i v e v o i c e t o t h e f a c t t h a t t h e s e d e c e p t i v e a c t i o n s w i l l c a u s e o p p o n e n t s t o h o l d b e l i e f s t h a t t h e y t h e m s e l v e s know t o b e f a l s e . B e c a u s e i t was assumed t h a t t h e s u b j e c t s i n t h e e a r l i e r C h a n d l e r , F r i t z a n d H a l a s t u d y h a d u n d e r t a k e n t h e i r h i d i n g e f f o r t s w i t h j u s t s u c h a c l e a r e x p e c t a t i o n t h a t t h e y w e r e f i r s t m a n i p u l a t i n g t h e i r o p p o n e n t ' s b e l i e f s a n d o n l y as a c o n s e q u e n c e 7 t h e i r act ions , rather than on the basis of some simpler behavioral strategy, i t was hypothesized that even the young 3-year-olds of the present study would c o r r e c t l y respond to questions about opponents b e l i e f s . F i n a l l y , i t could be argued that the youngest subjects i n the Chandler, F r i t z and Hala study simply forgot where they had hidden the treasure and so were never i n a p o s i t i o n to consider simultaneous but contrast ive notions about i t s true l o c a t i o n . Were t h i s the case, then any f a i l u r e on the part of the subjects of the present study to fol low what has come to be c a l l e d a " r e a l i t y assessment strategy" (Wellman & Bartsch, i n press) by i n d i c a t i n g that t h e i r opponent would search where the treasure was a c t u a l l y hidden could indicate that they had ended up deceiving themselves as wel l as others. That i s , responses of subjects to "belief" questions regarding t h e i r assumptions about the thoughts or l i k e l y search s trategies of t h e i r opponents are only in terpre tab le i n r e l a t i o n to t h e i r own r e c o l l e c t i o n s regarding the true loca t ion of the treasure . The responses of subjects who may have l o s t t rack of where they have previous ly hidden the treasure would allow room for uncertainty as to what i s a c t u a l l y meant when they indicate that t h e i r opponent i s l i k e l y to search i n a p a r t i c u l a r l o c a t i o n . To guard against t h i s poss ible source of i n t e r p r e t i v e confusion, the present study included memory contro l questions i n the deception procedure to ensure that subjects r e c a l l e d the actual l oca t ion of the treasure . Here the hypothesis was that subjects of a l l ages 8 would success fu l ly remember where they had hidden the treasure . Summary of Hypotheses In summary, then, the four hypotheses that guided the present study were as fol lows: 1) Like the c h i l d r e n of the Chandler, F r i t z and Hala study, subjects i n a l l age groups to be tested w i l l commonly take steps to dis inform t h e i r opponents i n the hide-and-seek task; 2) Subjects of a l l ages w i l l accurately remember the true h id ing l oca t ion of the treasure i n the h ide-and-seek task; 3) The youngest subjects (3-year-olds) w i l l f a i l a standard vers ion of the Wimmer-Perner unexpected change measure; while 4) The same subjects w i l l pass a comparable "belief" question i n the deception task. Before proceeding d i r e c t l y to the s p e c i f i c methods employed to tes t these hypotheses, i t might prove useful to fol low a more de ta i l ed summary of the research l i t e r a t u r e that guided the formulation of t h i s inquiry . The l i t e r a t u r e review provided i n Appendix A i s meant to supply t h i s supporting information. CHAPTER 2: METHOD 9 Procedural Summary Subjects A t o t a l of 33 c h i l d r e n between the ages of 3.0 and 4.5 years of age were r e c r u i t e d from a metropolitan preschool i n a Western Canadian c i t y . Chi ldren whose parents gave the necessary permission were excluded from the re su l t s only i f they refused to p a r t i c i p a t e i n some aspect of the procedure, such as manipulating the d o l l f igure or refus ing to hide the treasure i n the hide-and-seek task. On the basis of t h i s c r i t e r i a three subjects were dropped p r i o r to analys is (two 3-year-olds and one 3 .5 -year -o ld ) . The remaining 30 ch i ldren were d iv ided into three age groups with 10 subjects comprising each group: young 3-year-olds (range= 3.0 - 3.4, mean= 3.2, 5 males and 5 females); 3 .5-year-olds (range= 3.5 - 3.9, mean= 3.8, 4 males, 6 females) and young 4-year-olds (range= 4.0 - 4.4, mean= 4.2, 4 males, 6 females). A l l subjects p a r t i c i p a t e d i n both the unexpected change task and the deception task. The order of presentat ion of these two measures was counterbalanced with ha l f of the subjects being administered the unexpected change task f i r s t . The procedures were c a r r i e d out i n two separate t e s t i n g sessions to avoid subject fat igue and task demand s p i l l o v e r . What w i l l be described l a t e r as the " fa l s e -be l i e f t es t question" i n the deception task was always asked immediately a f ter each subject had completed h i s or her own h id ing e f for t s and immediately 10 b e f o r e t h e i r o p p o n e n t r e e n t e r e d t h e room. M a t e r i a l s B o t h t h e u n e x p e c t e d c h a n g e t a s k a n d t h e d e c e p t i o n t a s k i n v o l v e d t h e u s e o f a 92 cm x 82 cm w h i t e p l a y i n g s u r f a c e c o v e r e d w i t h a w a s h a b l e o i l c l o t h m a t e r i a l a n d 20 cm h i g h o p a q u e p l a s t i c c o n t a i n e r s w i t h l i d s ( 5 c o n t a i n e r s f o r t h e d e c e p t i o n t a s k a n d 2 f o r t h e u n e x p e c t e d c h a n g e t a s k ) . The u n e x p e c t e d c h a n g e t a s k u s e d two 33 cm h i g h h a n d p u p p e t s a n d a s m a l l t o y c a r ( s e e F i g u r e 1) w h i l e t h e d e c e p t i o n t a s k u s e d a k i t c h e n s p o n g e , a " t r e a s u r e " made up o f c h o c o l a t e c o i n s a n d s m a l l t r i n k e t s a n d one 33 cm p u p p e t mounted o n a w h e e l w i t h p r o j e c t i n g f e e t a t t a c h e d w h i c h r o t a t e l e a v i n g a s e t o f i n k y f o o t p r i n t s a s t h e p u p p e t i s moved ( s e e F i g u r e 2 ) . P r o c e d u r e U n e x p e c t e d Change T a s k As t h e s t r o n g e s t a n d mos t c o n s e r v a t i v e t e s t o f t h e s e v e r a l h y p o t h e s e s p r e s e n t e d h e r e , t h e most r e c e n t r e v i s i o n o f t h e u n e x p e c t e d c h a n g e t a s k ( P e r n e r , Leekam & Wimmer, 1987) was u s e d . T h i s v a r i a t i o n d i f f e r s m a r g i n a l l y f r o m t h e s e a u t h o r s ' own e a r l i e r v e r s i o n s o f t h i s p r o c e d u r e p r i m a r i l y i n t h a t memory a n d r e a l i t y p r o b e s a r e u s e d t h r o u g h o u t i n a n e f f o r t t o e n s u r e t h a t t h e s u b j e c t s u n d e r s t a n d a n d r e c a l l t h e r a t h e r c o m p l i c a t e d s t o r y t h a t u n f o l d s . A g a i n , f o l l o w i n g P e r n e r , Leekam a n d Wimmer's s u g g e s t i o n , " s t o p - a n d - t h i n k " i n s t r u c t i o n s w e r e i n c l u d e d i n t h i s p r o c e d u r e t o h e l p p r e v e n t i m p u l s i v e g u e s s i n g o n t h e p a r t o f t h e y o u n g e r s u b j e c t s . The o n l y s u b s t a n t i a l d i f f e r e n c e b e t w e e n t h e present "unexpected change" procedure and t h a t d e s c r i b e d by Perner e t a l . was t h a t , i n order t o i n s u r e the c l o s e s t p o s s i b l e match between t h i s procedure and the hide-and-seek t a s k d e s c r i b e d below, some of the same t e s t i n g m a t e r i a l s were used i n both measures. That i s , the same c o n t a i n e r s and s i m i l a r puppets were used t o guard a g a i n s t any p o s s i b l e p r e f e r e n c e s f o r one s e t of stimulus m a t e r i a l s over another t h a t might confound s u b j e c t s ' performance on the t a s k s . S u b j e c t s were seen i n d i v i d u a l l y by a s i n g l e experimenter wi t h whom the c h i l d r e n had gained some f a m i l i a r i t y i n the classroom. The t a s k was i n t r o d u c e d as a s h o r t puppet show which the c h i l d r e n were asked t o watch c a r e f u l l y because q u e s t i o n s were to be asked a t the end. Two puppets were shown t o a r r i v e at a room t h a t c o n t a i n e d two d i f f e r e n t c o l o u r e d (one red, one yellow) opaque c o n t a i n e r s t h a t look l i k e m i n i a t u r e p l a s t i c garbage cans. One of the puppets was c a r r y i n g a small toy c a r . The puppets were made t o p l a y t o g e t h e r w i t h the c a r and then t o g e t h e r put i t away i n the r e d c o n t a i n e r . The puppets were then c a l l e d away f o r snack time and both l e f t the room i n o p p o s i t e d i r e c t i o n s s a y i n g they would meet a f t e r snack t o p l a y again. One puppet ( K a t i e ) r e t u r n e d f i r s t and removed the toy c a r from the red c o n t a i n e r , played w i t h i t f o r a few minutes, but a f t e r h e a r i n g her t e a c h e r c a l l her back, l e f t the room once more. T h i s time, however, she put the toy c a r i n the ye l l o w c o n t a i n e r b e f o r e she l e f t the room. Soon the second puppet (Sam) was shown about t o r e t u r n and h i s d e s i r e t o once agai n p l a y w i t h the toy c a r was e x p l i c i t l y s t a t e d . A t t h i s p o i n t t h e f o l l o w i n g t e s t q u e s t i o n s w e r e a s k e d o f t h e s u b j e c t : "Does Sam know w h e r e t h e t o y c a r i s ? " , "Where w i l l Sam l o o k f o r t h e c a r ? " . I n a d d i t i o n t o t h e t e s t q u e s t i o n s o t h e r memory and r e a l i t y p r o b e s w e r e a s k e d t o i n s u r e t h a t t h e s u b j e c t f o l l o w e d t h e s e q u e n c e o f e v e n t s a n d remembered a l l t h e i m p o r t a n t d e t a i l s . As w e l l , a l l o f t h e v a r i o u s s t r a t e g i e s d e s c r i b e d b y P e r n e r e t a l . ( 1 9 8 7 ) t o a s s i s t t h e i r s u b j e c t s i n f o c u s i n g o n t h e r e l e v a n t d e t a i l s w e r e i n c l u d e d . F i n a l l y , s u b j e c t s w e r e a s k e d t o p r o v i d e j u s t i f i c a t i o n s f o r t h e i r r e s p o n s e s . The a d e q u a c y o f t h e s e j u s t i f i c a t i o n s d i d n o t i n f l u e n c e s u b j e c t s ' s c o r e s on t h e i g n o r a n c e a n d f a l s e - b e l i e f t e s t q u e s t i o n s a s t h e y h a v e p r e v i o u s l y b e e n f o u n d t o u n d e r e s t i m a t e y o u n g p r e s c h o o l c h i l d r e n ' s p e r f o r m a n c e o n f a l s e - b e l i e f t a s k s ( s e e P e r n e r e t a l . , 1987) b u t w e r e i n c l u d e d h e r e a s a n a i d t o i l l u m i n a t i n g any d i f f i c u l t i e s s u c h y o u n g s u b j e c t s may h a v e h a d w i t h t h e t a s k . The h i d e - a n d - s e e k t a s k I n t h e i n t e r e s t s o f m a k i n g t h e h i d e - a n d - s e e k t a s k m a t c h t h e u n e x p e c t e d c h a n g e m e a s u r e a s c l o s e l y a s p o s s i b l e , t h e C h a n d l e r e t a l . p r o c e d u r e was m o d i f i e d i n s e v e r a l m i n o r ways. M o s t n o t a b l y t h e p r o c e d u r e was s h o r t e n e d a n d a s t a n d a r d i z e d number o f t r i a l s ( 3 ) was u s e d r a t h e r t h a n r e q u i r i n g s u b j e c t s t o c o n t i n u e u n t i l t h e y h a d e x h a u s t e d t h e i r r e p e r t o i r e o f d e c e p t i v e s t r a t e g i e s . T h i s s h o r t e n i n g was done w i t h t h e a i m o f m i n i m i z i n g any e f f e c t s t h a t s i m p l e p r a c t i c e w i t h t h e m a t e r i a l s a n d p r o c e d u r e s m i g h t h a v e on c h i l d r e n ' s p e r f o r m a n c e on l a t e r t r i a l s . I n a d d i t i o n , r e a l i t y a n d memory c o n t r o l p r o c e d u r e s , w h i c h were not a part of the o r i g i n a l Chandler et a l . deception study, were introduced to determine whether the subjects remembered where they h i d the treasure . This procedure once again provided a better match to the unexpected change measure, and allowed for a more judic ious comparison. F i n a l l y , fo l lowing each of t h e i r separate h id ing e f for t s subjects were asked exact ly the same f a l s e - b e l i e f t es t questions which were used i n the unexpected change procedure. Subjects again were seen i n d i v i d u a l l y , t h i s time by two experimenters, both of whom were f a m i l i a r to the subject . The task was introduced as a hide-and-seek game that involved h id ing a small treasure somewhere on the game board so that the opponent could not f i n d i t . One experimenter (El) remained with the subject throughout the procedure to p h y s i c a l l y a s s i s t i n the h id ing operat ion, remind the subject of the ru les of the game and to ask the r e q u i s i t e probes and tes t questions. The second experimenter (E2) acted as the opponent. To ensure subjects had a grasp of the bas ic concepts of the game a b r i e f warm-up t r i a l without the puppet was conducted i n which the c h i l d took one turn as f i r s t f inder then as h ider . These t r i a l s were not included i n the scoring and were used instead as a method of introducing the goals and ru les of the game. Af ter t h i s short warm-up a puppet named Toni was introduced. I t was explained that Toni was r e a l l y the owner of the treasure and i t was the c h i l d ' s job to help Toni hide the treasure . The experimenter then demonstrated how Toni could be made to walk across the board, and at tent ion 14 was drawn t o the c l e a r t r a i l of inky f o o t p r i n t s t h a t the puppet l e f t behind. At t h i s p o i n t the t r a c k s were wiped away w i t h a damp k i t c h e n sponge t h a t was l e f t a v a i l a b l e f o r l a t e r use. The su b j e c t and E l took the f i r s t t u r n i n the f i n d e r s ' r o l e , l e a v i n g the room w h i l e E2 h i d the t r e a s u r e i n one of the c o n t a i n e r s . When the s u b j e c t r e e n t e r e d the room, a c l e a r s e t of f o o t p r i n t s marked the l o c a t i o n of the t r e a s u r e . T h i s s t e p served t o ensure t h a t s u b j e c t s made the p o t e n t i a l connection between the f o o t p r i n t s and the l o c a t i o n of the t r e a s u r e . I f the s u b j e c t f a i l e d t o make use of the f o o t p r i n t s i n the search f o r the t r e a s u r e the f o o t p r i n t s were e x p l i c i t l y p o i n t e d out and the t r i a l repeated. In the second and most c r i t i c a l p a r t of the procedure i t became the s u b j e c t ' s t u r n t o a c t i n the r o l e of h i d e r , and t h i s time E2 l e f t the room. The f i r s t experimenter then reminded the su b j e c t of the r u l e t h a t the puppet Toni must be used t o hid e the t r e a s u r e and simply a s s i s t e d i n c a r r y i n g out whatever t a s k s were i n i t i a t e d by the s u b j e c t . Once the t r e a s u r e was hidden, thereby l e a v i n g a t r a i l of f o o t p r i n t s on the board, E l reminded the su b j e c t t h a t the goal was t o make i t hard f o r E2 t o f i n d the t r e a s u r e and asked the s u b j e c t how t h a t c o u l d be done. R e a l i t y probes a k i n t o those used i n the Perner e t a l . unexpected change paradigm were used throughout. When the s u b j e c t had completed h i s o r her h i d i n g e f f o r t s E l asked "Do you remember where you h i d the t r e a s u r e " , "show me". F i n a l l y , the two c r i t i c a l t e s t q uestions were asked be f o r e E2 was c a l l e d back: (1) The " i g n o r a n c e " q u e s t i o n , " W i l l E2 know w h e r e t h e t r e a s u r e i s ? " ; a nd (2 ) The " f a l s e - b e l i e f " q u e s t i o n , "Where w i l l E2 l o o k ? " . When E2 r e t u r n e d , i f t h e s u b j e c t h a s a c t e d s t r a t e g i c a l l y , E l s u r r e p t i t i o u s l y s i g n a l e d t h e t r u e l o c a t i o n o f t h e t r e a s u r e t o p r e v e n t E 2 ' s a c c i d e n t l y f i n d i n g i t on t h e f i r s t a t t e m p t . A f t e r a f i r s t f a i l e d a t t e m p t E2 was g i v e n a n o t h e r c h a n c e . A t t h i s p o i n t t h e s u b j e c t was p r o v i d e d f u r t h e r o p p o r t u n i t y f o r d e c e p t i o n b y b e i n g a s k e d "Where s h a l l we t e l l E2 t o l o o k now". S u b j e c t s w e r e a s k e d t o j u s t i f y o r e x p l a i n t h e i r h i d i n g s t r a t e g i e s b u t a s w i t h t h e u n e x p e c t e d c h a n g e t a s k t h e s e j u s t i f i c a t i o n s d i d n o t e n t e r i n t o t h e s c o r i n g o f t h e s e s t r a t e g i e s a s d e c e p t i v e o r n o n d e c e p t i v e . A maximum o f two more h i d i n g t r i a l s w e r e t h e n r e p e a t e d e x a c t l y a s d e s c r i b e d a b o v e . S c o r i n g U n e x p e c t e d Change T a s k As i n t h e P e r n e r e t a l . ( 1 9 8 7 ) s t u d y a d i c h o t o m o u s s c o r i n g p r o c e d u r e was e m p l o y e d . S u b j e c t s w e r e s c o r e d a s p a s s i n g t h e f a l s e - b e l i e f t e s t q u e s t i o n i f t h e y r e s p o n d e d t o t h e q u e s t i o n , "Where w i l l Sam l o o k f o r t h e t o y c a r when he r e t u r n s ? " b y c o r r e c t l y p o i n t i n g t o t h e c o n t a i n e r i n w h i c h t h e t o y c a r h a d i n f a c t b e e n o r i g i n a l l y p l a c e d . S u b j e c t s who f o l l o w e d a " r e a l i t y a s s e s s m e n t s t r a t e g y " b y i n c o r r e c t l y p o i n t i n g t o t h e c o n t a i n e r i n w h i c h t h e t o y c a r a c t u a l l y was l o c a t e d w e r e s c o r e d a s h a v i n g f a i l e d . S i m i l a r l y , s u b j e c t s who r e s p o n d e d c o r r e c t l y t h a t t h e u n i n f o r m e d p u p p e t w o u l d n o t know where t h e t o y c a r was w e r e 16 scored as passing the ignorance tes t question. While not used to determine p a s s / f a i l performance on t h i s task, subjects also were asked to j u s t i f y t h e i r answers. These responses were coded dichotomously as to t h e i r adequacy. Hide-and-Seek Task Scoring for t h i s measure of f a l s e - b e l i e f understanding i s somewhat more complex than for the unexpected change procedure as there ex i s t several poss ib le s trategies subjects could employ i n attempting to deceive t h e i r opponent. Chandler, F r i t z and Hala ( in press) , set out a typology of deception s trateg ies into which subjects' responses were r e l i a b l y placed. This f i ve l e v e l typology orders the various s t ra teg i c actions ava i lab le to the subjects i n terms of the c e r t a i n t y they provide that deception has a c t u a l l y occurred but t h i s order does not r e f l e c t any assumptions regarding h i e r a r c h i c a l r e l a t i o n s of increas ing complexity of s trateg ies . Once actions are assigned to a s p e c i f i c l e v e l within t h i s typology a further dichotomous categor izat ion can be made in to deceptive-nondeceptive actions i n order to f a c i l i t a t e comparison with re su l t s on the unexpected change task. The f i r s t l e v e l i n t h i s typology, l e v e l 0, categorizes as nondeceptive both those act ions that are t o t a l l y devoid of any apparent attempt at deception (e .g. leaving c l e a r foo tpr in t s to the loca t ion of the treasure) , and also any act ions that might conceivably have had deceptive intent , but were too ambiguous to be unequivocally coded as deceptive. Responses assigned to t h i s l a t t e r category i n c l u d e d such a c t i o n s as: a) the simple w i t h h o l d i n g of evidence by making sure t h a t any c o n t a i n e r s t h a t had been moved were r e t u r n e d t o t h e i r o r i g i n a l l o c a t i o n ; b) e f f o r t s on the p a r t of the s u b j e c t t o make sure t h a t E2 was not peeking d u r i n g the h i d i n g procedure; c) not t e l l i n g E2 the l o c a t i o n of the t r e a s u r e ; and d) attempts at h i d i n g the t r e a s u r e t h a t i n v o l v e d some s o r t of "smokescreen" of i r r e l e v a n t but not o b s c u r i n g c l u e s . The remaining l e v e l s of the d e c e p t i o n t y p o l o g y concern responses which go beyond attempts at simple s e c r e t keeping, and i n s t e a d e v i d e n t l y i n v o l v e some de c e p t i v e i n t e n t and a c t i o n . L e v e l 1, d e s t r o y i n g evidence, i n c l u d e s those attempts t o remove any c l u e s l e f t d u r i n g the h i d i n g procedure by wiping up the puppet's t e l l - t a l e t r a c k s . L e v e l 2, l y i n g , r e p r e s e n t s s u b j e c t s ' attempts t o m i s l e a d t h e i r opponent by s u g g e s t i n g t h a t they look f o r the t r e a s u r e i n an empty c o n t a i n e r . L e v e l 3, producing f a l s e  t r a i l s , i n c l u d e s a l l attempts on the p a r t of the s u b j e c t t o l a y one or more s e t s of a d d i t i o n a l t r a i l s t o some empty c o n t a i n e r . The f i n a l l e v e l , l e v e l 4, d e s t r o y i n g evidence and producing f a l s e  t r a i l s , was used whenever s u b j e c t s combined the s t r a t e g y of producing f a l s e t r a i l s (no. 3) w i t h the s t r a t e g y of removal of the o r i g i n a l s e t of t e l l - t a l e f o o t p r i n t s (no. 2), r e s u l t i n g i n l e a v i n g only m i s l e a d i n g c l u e s f o r the opponent t o f o l l o w . F o r the purposes of the data analyses to be r e p o r t e d below l e v e l s 0 and 1 i n t h i s s c o r i n g scheme were coded as nondeceptive and o n l y responses scored i n l e v e l s 2, 3, and 4 were counted as evidence 18 of c l e a r deception. Scoring of the f a l s e - b e l i e f t e s t question asked during the hide-and-seek procedure i s a lso a somewhat more complex task than for the unexpected change procedure which simply requires the subject to ind icate i n which of two containers the only p a r t i a l l y informed puppet w i l l look for the concealed toy car . While exact ly the same tes t question was asked i n the hide-and-seek task, what counts as a correct response d i f f e r s from subject to subject and even from t r i a l to t r i a l depending upon the type of h id ing s trateg ies employed. If , for example, a subject had l e f t only one c l e a r , but f a l s e , set of tracks leading to an empty container, then the most r a t i o n a l a t t r i b u t i o n the subject could make i s the E2 would search i n that s ingle f a l s e l y nominated container. If , however, the subject has produced tracks to a l l of the remaining containers , then the most r a t i o n a l response would be that E2 would be obl iged to look i n each and every container. In fac t , many subjects spontaneously appreciated t h i s consequence of t h e i r h id ing e f for t s and would counter by saying "But I w i l l t e l l her to look i n t h i s one" i n d i c a t i n g one of the f a l s e l y nominated containers . There also existed the r e a l p o s s i b i l i t y that subjects might respond i n any one of several ways that were a l l i r r a t i o n a l i n that they were unrelated to the ava i lab le evidence (e.g. suggesting that E2 would look i n a container that had no clues i n d i c a t i n g that i t contained the treasure) . A spec ia l case of t h i s larger c lass of i r r a t i o n a l responses i s provided by responses i n which the subject indicates 19 that E2 would look i n the container that a c t u a l l y concealed the treasure , despite the presence of ava i lab le evidence i n d i c a t i n g otherwise. Responses of t h i s sort are re ferred to here as a r e a l i t y assessment s trategies because subjects employing them appear to be basing t h e i r assessment of another's b e l i e f s upon the state of the world as i t r e a l l y i s rather than as the other might have reason to be l ieve i t to be. Note that while the term r e a l i t y assessment might i n some s i tuat ions connote an achievement i n cogni t ive development i n t h i s case i t c a r r i e s a more negative connotation and i s meant to character ize f a i l u r e on the part of c h i l d r e n to d i s t i n g u i s h what i s r e a l l y the case from what t h e i r opponent has a r i g h t to be l ieve based on the evidence a v a i l a b l e . Responses based upon such r e a l i t y assessment s trategies are p r e c i s e l y those which young 3-year-olds are sa id to rout ine ly make i n the unexpected change task. Given t h i s range of p o s s i b i l i t i e s the scor ing of subjects ' responses involved p lac ing them into a dichotomous categor izat ion of r e a l i t y assessment s trateg ies versus r a t i o n a l  assessment s tra teg ies . The term r a t i o n a l assessment s trategies serves as a contrast to r e a l i t y assessment s trateg ies and draws at tent ion to the fact that subjects employing such s trateg ies a t t r ibute to t h e i r opponents courses of act ion that r a t i o n a l l y fol low on the bas is of evidence ava i lab le to them. Although, as indicated above, i t was t e c h n i c a l l y poss ib le for subjects to generate "nonrational" responses other than those r e s u l t i n g from the app l i ca t ion of a simple r e a l i t y assessment strategy, such choices were rare (n=2). Whatever e lse they might s i g n a l , they d id not ind ica te that the subjects understood the l i k e l y impact of ava i lab le evidence upon E2's search response and so were conservat ively counted here as instances of r e a l i t y assessment  s trateg ies . A s i m i l a r course of act ion was taken i n those few instances (n=2) i n which subjects f a i l e d to act decept ive ly . While a case might have been made to exclude these subjects on the grounds that s ince a l l of the ava i l ab l e evidence pointed to where the treasure was a c t u a l l y located, no r e a l opportunity was ava i lab le for subjects to employ any strategy but a r e a l i t y assessment strategy. Again, i n an e f f o r t to choose a course of act ion that d id not favour the hypotheses guiding t h i s study, these cases were counted as true instances of a r e a l i t y assessment strategy. CHAPTER 3: RESULTS 21 The c e n t r a l q u e s t i o n w h i c h t h i s s t u d y was i n t e n d e d t o a n s w e r i s w h e t h e r c h i l d r e n y o u n g e r t h a n 4 y e a r s o f age do i n f a c t p o s s e s s some t h e o r y - l i k e u n d e r s t a n d i n g o f t h e i r own a n d o t h e r s ' m e n t a l l i v e s , a s e v i d e n c e d b y t h e i r a b i l i t y t o e n g a g e i n d e c e p t i v e h i d i n g p r a c t i c e s a n d t o a n t i c i p a t e t h e c o n s e q u e n c e s o f t h e s e d e c e p t i v e a c t s o n t h e b e l i e f s o f o t h e r s . The f o l l o w i n g r e s u l t s , w h i c h a r e i n t e n d e d t o a n s w e r t h e s e q u e s t i o n s , a r e o r g a n i z e d i n t o t h r e e s e c t i o n s . The f i r s t o f t h e s e s u m m a r i z e s t h e f i n d i n g s o f an a t t e m p t t o r e p l i c a t e t h e r e s u l t s o f t h e e a r l i e r * C h a n d l e r , F r i t z a n d H a l a s t u d y ( i n p r e s s ) , u p o n w h i c h t h i s i n v e s t i g a t i o n was p r e d i c a t e d . P a r t two d e s c r i b e s r e s u l t s f r o m a c o n c u r r e n t a t t e m p t t o e v a l u a t e t h e p e r f o r m a n c e o f t h e same s u b j e c t s on a n a l t e r n a t i v e f a l s e - b e l i e f t a s k , t h e s t a n d a r d " u n e x p e c t e d c h a n g e m e a s u r e " o r i g i n a l l y i n t r o d u c e d b y J o h n s o n a n d M a r a t s o s ( 1 9 7 7 ) a nd s u b s e q u e n t l y p o p u l a r i z e d b y Wimmer and P e r n e r a n d t h e i r c o l l e a g u e s ( s e e P e r n e r e t a l . 1 9 8 7 ) . F i n a l l y , a n d mos t i m p o r t a n t l y , P a r t t h r e e w i l l p r e s e n t t h e r e s u l t s o f a n o v e l a t t e m p t t o t r a n s p o r t t h e k e y " b e l i e f " q u e s t i o n , upon w h i c h t h e i n t e r p r e t a t i o n o f r e s u l t s f r o m s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e s r e g u l a r l y h i n g e , i n t o t h e d e c e p t i v e h i d i n g p a r a d i g m f e a t u r e d i n t h i s s t u d y . H e r e t h e k e y i s s u e i s w h e t h e r c h i l d r e n who a r e a b l e t o a c t i v e l y d e c e i v e a l s o u n d e r s t a n d t h a t t h e i r m i s l e a d i n g a c t i o n s a c t u a l l y p r o m o t e f a l s e b e l i e f s i n o t h e r s . O r d e r a n d S e x E f f e c t s 22 The a p p r o p r i a t e n e s s o f t h i s s e r i a l a p p r o a c h t o t h e p r e s e n t a t i o n o f t h e r e s u l t s n e c e s s a r i l y p r e s u p p o s e s t h a t t h e s e p a r a t e f i n d i n g s f r o m t h e d i f f e r e n t f a l s e - b e l i e f m e a s u r e s a r e a c t u a l l y i n d e p e n d e n t o f t h e o r d e r i n w h i c h t h e y w e r e c o l l e c t e d . B a s e d o n a oneway a n a l y s i s o f v a r i a n c e , t a s k o r d e r was n o t f o u n d t o h a v e a n y s i g n i f i c a n t e f f e c t o n t h e p e r f o r m a n c e o f s u b j e c t s i n any o f t h e s e t a s k s . P a r e n t h e t i c a l l y , a s e c o n d oneway a n a l y s i s o f v a r i a n c e r e v e a l e d no s i g n i f i c a n t e f f e c t f o r s e x o f s u b j e c t f o r any o f t h e m e a s u r e s , w a r r a n t i n g t h e c o m b i n a t i o n o f t h e d a t a f r o m b o t h m a l e a n d f e m a l e s u b j e c t s . P a r t I : R e p l i c a t i on o f t h e C h a n d l e r , F r i t z a n d H a l a s t u d y As d e s c r i b e d e a r l i e r , t h e C h a n d l e r e t a l . s t u d y d e m o n s t r a t e d t h a t c h i l d r e n a s y o u n g a s t h r e e y e a r s o f age t o o k a p p r o p r i a t e s t e p s t o d e c e i v e a n o p p o n e n t i n a h i d e - a n d - s e e k game, b o t h s u p p o r t i n g t h e c o n c l u s i o n s t h a t t h e y a l r e a d y h a d a w o r k i n g u n d e r s t a n d i n g o f f a l s e b e l i e f a n d , c o n s e q u e n t l y , some o p e r a t i v e t h e o r y o f m i n d . F o l l o w i n g t h e s c o r i n g c o n v e n t i o n s i n t r o d u c e d i n t h e C h a n d l e r e t a l . s t u d y a n d f u r t h e r d e s c r i b e d i n C h a p t e r 2 o f t h i s r e s e a r c h r e p o r t , an i n i t i a l e x a m i n a t i o n o f t h e t y p e s o f d e c e p t i v e s t r a t e g i e s e m p l o y e d a c r o s s t h e t h r e e age g r o u p s s t u d i e d ( s e e t a b l e 1) p r o v i d e s a c l e a r d e m o n s t r a t i o n t h a t e v e n t h e y o u n g e s t s u b j e c t s o f t h i s s t u d y d i d a c t i v e l y u n d e r t a k e t o d e c e i v e t h e i r 23 I n s e r t t a b l e 1 a b o u t h e r e o p p o n e n t s . I n l i n e w i t h t h e h i g h s c o r i n g r e l i a b i l i t y f o u n d i n t h e C h a n d l e r e t a l . s t u d y , b a s e d on a p p r o x i m a t e l y 2 6 % o f s u b j e c t s ' r e s p o n s e s ( a t o t a l o f 8 s u b j e c t s ) p e r f e c t ( 1 0 0 % ) a g r e e m e n t was o b t a i n e d b e t w e e n two i n d e p e n d e n t r a t e r s i n t h e p r e s e n t s t u d y . B e f o r e p r o c e e d i n g t o a more d e t a i l e d e x a m i n a t i o n o f t h e o v e r a l l r e s u l t s u s i n g t h e h i d e - a n d - s e e k t a s k , h o w e v e r , i t i s i m p o r t a n t t o d e s c r i b e j u s t how t h e s u b j e c t s ' i n d i v i d u a l h i d i n g e f f o r t s w e r e s u m m a r i z e d and a s s i g n e d t o e a c h o f t h e s e v e r a l s c o r i n g c a t e g o r i e s o u t l i n e d i n t h i s t a b l e . I n b r i e f , a l t h o u g h a t o t a l o f t h r e e t r i a l s was a l l o w e d , a s u f f i c i e n t l y l a r g e number o f s u b j e c t s ( 2 7 % ) c o m p l e t e d o n l y t w o h i d i n g t r i a l s . C o n s e q u e n t l y , t h e a n a l y s e s t o be r e p o r t e d w e r e b a s e d o n l y on t r i a l s one and two. F u r t h e r , b e c a u s e t h e r e a r e no g r o u n d s f o r a s s u m i n g t h a t a n y g i v e n s u b j e c t ' s b e s t p e r f o r m a n c e w o u l d o c c u r on one o r t h e o t h e r o f t h e s e t r i a l s , a n d b e c a u s e t h e i n t e n t i o n was t o a s s e s s t h e i r c a p a c i t y f o r a c t i n g d e c e p t i v e l y , s u b j e c t s w e r e s c o r e d i n t e r m s o f t h e i r b e s t p e r f o r m a n c e a c r o s s t h e s e f i r s t two t r i a l s . T h i s s c o r i n g c o n v e n t i o n a l s o accommodated t h e f a c t t h a t t h e s t r a t e g y o f d e s t r o y i n g e v i d e n c e b y w i p i n g up t h e p u p p e t ' s t r a c k s was t h e i n i t i a l r e s p o n s e o f c h o i c e o f h a l f ( 5 0 % ) o f t h e s u b j e c t s . W h i l e t h i s i s a n e s p e c i a l l y e f f e c t i v e h i d i n g t e c h n i q u e , t h e f a c t t h a t s u c h r e s p o n s e s a r e l e s s c l e a r l y i n t e r p r e t a b l e a s a t t e m p t s a t d e c e p t i o n t h a n a r e l y i n g o r t h e l a y i n g o f f a l s e t r a c k s , s u c h r e s p o n s e s w e r e c a u t i o u s l y e x c l u d e d f r o m t h e l i s t o f u n a m b i g u o u s measures of d e c e i t . Given t h i s p r a c t i c e , r e l y i n g upon t r i a l one alone or averaging t r i a l s one and two would have c r e a t e d a m i s l e a d i n g p i c t u r e of s u b j e c t s ' a b i l i t i e s t o a c t i v e l y d i s i n f o r m o t h e r s . As can be seen from a f u r t h e r examination of t a b l e 1, the v a r i o u s types of h i d i n g s t r a t e g i e s used by i n d i v i d u a l s u b j e c t s are d i s t r i b u t e d r e l a t i v e l y evenly a c r o s s the t h r e e age groups. As i n the Chandler, F r i t z and Hala study, the b e s t s i n g l e measure of the o v e r a l l a b i l i t y of these young s u b j e c t s t o deceive comes from an examination of the p r o p o r t i o n s of c h i l d r e n a t each age who evidenced any h i d i n g e f f o r t s t h a t can be regarded as unambiguously d e c e p t i v e . Consequently, f o r the purpose of t h i s a n a l y s i s , those a c t i o n s t h a t c o u l d be s a i d t o o n l y serve as " s e c u r i t y f u n c t i o n s " by w i t h h o l d i n g or d e s t r o y i n g t e l l - t a l e evidence were r e l e g a t e d t o the category of nondeceptive responses. I t i s important t o be c l e a r about j u s t how c o n s e r v a t i v e t h i s s t r i n g e n t d e f i n i t i o n of d e c e p t i o n a c t u a l l y i s . There i s an a c t i v e l i t e r a t u r e on d e c e p t i o n r e g a r d i n g human and other s p e c i e s (e.g. M i t c h e l l & Thompson, 1986) most of which i s s a t i s f i e d t o count the w i t h h o l d i n g of evidence (e.g., i n t h i s measurement paradigm simply demonstrating c a u t i o n i n r e t u r n i n g c o n t a i n e r s t o t h e i r o r i g i n a l p o s i t i o n on the p l a y i n g s u r f a c e ) as proof of d e c e p t i v e i n t e n t . The a c t u a l wiping up of the puppet's t r a c k s which i s r e f e r r e d to here as a s t r a t e g y f o r " d e s t r o y i n g evidence", i n v o l v e s a much more a c t i v e e f f o r t on the p a r t of s u b j e c t s t o r e a c h backwards i n time and e l i m i n a t e t e l l - t a l e 25 e v i d e n c e o f t h e i r e a r l i e r b e h a v i o u r . As s u c h , s t r a t e g i e s o f t h i s s o r t m i g h t w e l l h a v e b e e n a r g u e d t o b e a t y p e o f d i s i n f o r m i n g a c t an d t h u s , e x c l u d i n g t h e s e h i g h l y e f f i c i e n t h i d i n g p r a c t i c e s f r o m t h e c a t e g o r y o f d e c e p t i o n c l e a r l y w o r k s a g a i n s t t h e p r e s e n t h y p o t h e s i s t h a t e v e n y o u n g 3 - y e a r - o l d s a l r e a d y p o s s e s s some t h e o r y o f m i n d . E v e n u s i n g t h i s s t r i n g e n t c r i t e r i a , a n d d i c h o t o m i z i n g r e s p o n s e s i n t o d e c e p t i v e a n d n o n d e c e p t i v e a c t s , I n s e r t t a b l e 2 a b o u t h e r e a s c a n be s e e n b y an e x a m i n a t i o n o f t h i s t a b l e , a l m o s t a l l s u b j e c t s ( 9 3 % ) a c t e d d e c e p t i v e l y . H i e r a r c h i c a l l o g l i n e a r a n a l y s i s was a p p l i e d t o t h e s e d a t a s t a r t i n g w i t h a s a t u r a t e d m o d e l a n d u s i n g a b a c k w a r d i t e r a t i o n t o f i n d t h e m o d e l o f b e s t f i t . The a n a l y s i s r e v e a l s t h a t t h e m o d e l t h a t t h e t w o way e f f e c t s o f t h e i n t e r a c t i o n o f age a n d t a s k p e r f o r m a n c e a r e z e r o c a n n o t b e r e j e c t e d ( G 2 = 1.692, 2, p = .59) a n d t h a t t h e one way e f f e c t o f t a s k p e r f o r m a n c e p r o v i d e s t h e b e s t f i t t i n g m o d e l f o r t h e d a t a ( G 2 = 1.69, 4, p = . 7 9 ) . T h e s e r e s u l t s i n d i c a t e t h a t t h e r e i s no s i g n i f i c a n t e f f e c t o f age a n d t h u s a r e i n k e e p i n g w i t h t h o s e o b t a i n e d b y C h a n d l e r e t a l . a n d a g a i n p r o v i d e s t r o n g s u p p o r t f o r t h e c l a i m t h a t e v e n when v e r y c o n s e r v a t i v e s c o r i n g c r i t e r i a a r e e m p l o y e d c h i l d r e n a s y o u n g a s 3 y e a r s o f age a r e c a p a b l e o f a c t i n g d e c e p t i v e l y . P a r t I I : S t a n d a r d U n e x p e c t e d Change M e a s u r e A s e c o n d f o c u s o f t h i s r e s e a r c h was upon t h e r e s p o n s e s o f these same subjects to Wimmer and Perner's standard unexpected change task. The methods employed here c lo se ly conform to the revised vers ion of the adminis trat ion and scor ing procedure recent ly introduced by Perner et a l . (1987), which included several memory and r e a l i t y probes e n l i s t e d to ensure that subjects ac tua l ly fol low the convoluted p lots required by t h i s task. Three such contro l questions were asked of subjects fo l lowing the unexpected change: 1) "Where i s the toy car now?" 2) "Where d id Kat ie and Sam (the two puppets) put the toy car at the beginning?"; and 3) "Did Sam see the toy car being moved?". These contro l questions were answered c o r r e c t l y by a l l subjects . Ignorance t e s t question. Subjects responded to the f i r s t t es t question regarding whether the absent puppet knew where the toy car was e i ther c o r r e c t l y by rep ly ing "no" or i n c o r r e c t l y by s ta t ing "yes". As shown i n table 3 the re su l t s are i n l i n e with previous research ( e . g . , Hogrefe, Wimmer & Perner, 1986; Perner et a l . , 1987; Wimmer & Perner, 1983) with almost a l l of the young 3-year-olds having responded i n c o r r e c t l y while most of the 3 .5-year-olds and a l l of the 4-year-olds responded c o r r e c t l y . H i e r a r c h i c a l l o g l i n e a r analys is demonstrates that the best f i t t i n g model i s one i n which age and task success in terac t and that a tes t that the two way e f fects of age and task success are zero i s re jec ted (G2 = 21.66, 2, p < .001). Insert table 3 about here 27 F a l s e - b e l i e f t e s t q u e s t i o n R e s p o n s e s o f s u b j e c t s t o t h e s t a n d a r d " f a l s e b e l i e f " p e r f o r m a n c e q u e s t i o n o f "Where w i l l Sam L o o k ? " w e r e s c o r e d a s e i t h e r p a s s . when s u b j e c t s i n d i c a t e d t h a t Sam w o u l d a c t a p p r o p r i a t e l y b y l o o k i n g i n t h e o r i g i n a l c o n t a i n e r ( i . e . , w h ere he h a d l a s t s e e n t h e c a r p u t ) , o r f a i l . when s u b j e c t s m i s t a k e n l y i n d i c a t e d t h a t Sam w o u l d l o o k i n t h e c o n t a i n e r t h a t now a c t u a l l y h e l d t h e t o y c a r . The r e s u l t s shown i n t a b l e 4 show t h a t , a s I n s e r t t a b l e 4 a b o u t h e r e p r e d i c t e d , when u s i n g t h i s s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e o f f a l s e - b e l i e f u n d e r s t a n d i n g , t h e f i n d i n g s w e r e c o m p a r a b l e w i t h t h o s e r e c e n t l y o b t a i n e d e l s e w h e r e ( e . g . P e r n e r e t a l . , 1987) w i t h 8 0 % o f 3 - y e a r - o l d s m i s t a k e n l y c h o o s i n g t h e a c t u a l l o c a t i o n o f t h e t o y c a r a s t h e p l a c e i n w h i c h Sam w o u l d s e a r c h . I n c o n t r a s t t o t h i s p o o r p e r f o r m a n c e m o s t o f t h e 3.5- and 4 - y e a r - o l d s c o r r e c t l y i n d i c a t e d t h a t Sam w o u l d s e a r c h i n t h e l o c a t i o n w h ere he a n d t h e o t h e r p u p p e t f i g u r e h a d a c t u a l l y l e f t i t . H i e r a r c h i c a l l o g l i n e a r a n a l y s i s i n d i c a t e s t h a t a m o d e l i n w h i c h t h e two way e f f e c t s o f t a s k p e r f o r m a n c e and age p r o v i d e s t h e b e s t f i t and d e l e t i o n o f t h i s i n t e r a c t i o n e f f e c t s i g n i f i c a n t l y a l t e r s t h e g o o d n e s s o f f i t (G2 = 11.654, 2, p < . 0 1 ) . I g n o r a n c e " V e r s u s " F a l s e - b e l i e f C o n t r a r y t o t h e f i n d i n g s o f H o g r e f e e t a l . ( 1 9 8 6 ) , i n w h i c h a d e v e l o p m e n t a l l a g was f o u n d t o e x i s t b e t w e e n t h e a b i l i t y o f 28 s u b j e c t s t o f i r s t p a s s t h e " i g n o r a n c e " q u e s t i o n , a n d t h e i r s u b s e q u e n t a b i l i t y t o p a s s t h e " f a l s e - b e l i e f " q u e s t i o n , s u b j e c t s a t a l l a g e s i n t h i s s t u d y c o n s i s t e n t l y t e n d e d t o e i t h e r p a s s o r f a i l b o t h o f t h e s e t a s k s t o g e t h e r , w i t h t h e same numbers o f s u b j e c t s i n e a c h age g r o u p p a s s i n g t h e f a l s e - b e l i e f q u e s t i o n a f t e r f a i l i n g t h e i g n o r a n c e q u e s t i o n a s s h o w i n g t h e r e v e r s e p a t t e r n . T h e s e f i n d i n g s , a l o n g w i t h t h e r e s u l t s o f a w i t h i n -s u b j e c t a n a l y s i s u s i n g McNemar's t e s t f o r c o r r e l a t e d p r o p o r t i o n s w h i c h t e s t s t h e e q u a l i t y o f two p r o p o r t i o n s , a r e r e p o r t e d i n t a b l e 5 (McNemar P-1) and i n d i c a t e t h e h i g h c o n s i s t e n c y f o u n d i n s u b j e c t s ' r e s p o n s e s t o t h e two t e s t q u e s t i o n s . I n s e r t t a b l e 5 a b o u t h e r e  D e c e p t i o n v e r s u s U n e x p e c t e d Change M e a s u r e I n a g r e e m e n t w i t h t h e r e s u l t s r e p o r t e d b y C h a n d l e r e t a l . , b u t i n s h a r p c o n t r a s t t o o t h e r f i n d i n g s b a s e d u p on v a r i o u s m e a s u r e s o f u n e x p e c t e d c h a n g e , t h e r e s u l t s o f t h i s s t u d y a g a i n d e m o n s t r a t e t h a t c h i l d r e n w e l l u n d e r t h e age o f 4 y e a r s a r e c a p a b l e o f a c t i v e l y l e a d i n g a n o t h e r i n t o f a l s e b e l i e f s a b o u t t h e l o c a t i o n o f h i d d e n o b j e c t s . F i g u r e 3 d e p i c t s a d i r e c t b e t w e e n -g r o u p s c o m p a r i s o n o f t h e p e r f o r m a n c e o f s u b j e c t s on t h e s e two t a s k s . C o n s i s t e n t w i t h t h e h y p o t h e s e s t h a t g u i d e d t h i s s t u d y , t h e I n s e r t f i g u r e 3 a b o u t h e r e most s t r i k i n g d i f f e r e n c e t o be o b s e r v e d i n t h e s e d a t a o c c u r s i n the young 3-year-old age group. Whereas o n l y 20% of these young s u b j e c t s pass the unexpected change measure, 90% demonstrated the a b i l i t y t o a c t d e c e p t i v e l y i n the hide-and-seek task. A w i t h i n -s u b j e c t comparison p r o v i d e s an even s t r o n g e r demonstration t h a t the 3-year-olds i n t h i s study performed s i g n i f i c a n t l y b e t t e r on the d e c e p t i o n t a s k than on the unexpected change tas k . Table 6 shows a two by two contingency t a b l e of performance on the two competing t a s k s . As can be seen by an examination of t h i s t a b l e 10 of the s u b j e c t s who f a i l e d the unexpected change measure of I n s e r t t a b l e 6 about here f a l s e - b e l i e f were capable of t a k i n g d e c e p t i v e a c t i o n i n the hide-and-seek t a s k while no s u b j e c t s showed the r e v e r s e p a t t e r n . An a n a l y s i s u s i n g McNemar's t e s t f o r c o r r e l a t e d p r o p o r t i o n s r e v e a l s s i g n i f i c a n t d i f f e r e n c e s i n performance on the two t a s k s (p<.01) i n d i c a t i n g t h a t s u b j e c t s had more d i f f i c u l t y i n responding c o r r e c t l y d u r i n g the unexpected change procedure. P a r t I I I : P r e d i c t i n g F a l s e B e l i e f i n the Deception Task In s p i t e of the impressive performance of young 3-year-olds observed on the hide-and-seek task, the q u e s t i o n may s t i l l remain as t o whether a c t i n g i n t h i s a p p a r e n t l y d e c e p t i v e way can be i n t e r p r e t e d unambiguously as proof t h a t these young s u b j e c t s a c t u a l l y a p p r e c i a t e d t h a t t h e i r m i s l e a d i n g a c t i o n s would r e s u l t i n g e n e r a t i n g f a l s e b e l i e f s i n t h e i r opponents. The i n c l u s i o n w i t h i n the new hide-and-seek t a s k of a p a r a l l e l v e r s i o n of the 30 s t a n d a r d " f a l s e - b e l i e f " t e s t q u e s t i o n t h a t i s s o c e n t r a l t o a l l u n e x p e c t e d c h a n g e m e a s u r e s , was i n t e n d e d a s a d i r e c t m e t h o d o f s e t t l i n g t h i s u n c e r t a i n m a t t e r . B e f o r e p r o c e e d i n g t o a n e x a m i n a t i o n o f t h e s e r e s u l t s , h o w e v e r , i t was n e c e s s a r y t o d e t e r m i n e w h e t h e r s u b j e c t s t h e m s e l v e s a c t u a l l y remembered w h e r e t h e y h a d h i d d e n t h e t r e a s u r e . S u b s e q u e n t t o a n y h i d i n g s t r a t e g y , w h e t h e r d e c e p t i v e o r n o n d e c e p t i v e , s u b j e c t s t h e r e f o r e w e r e a s k e d "Do y o u remember w h e r e y o u h i d t h e t r e a s u r e ? " , "Show me". R e s p o n s e s w e r e s c o r e d a s c o r r e c t i f s u b j e c t s i n d i c a t e d t h e a c t u a l l o c a t i o n o f t h e t r e a s u r e . A c r o s s a l l s u b j e c t s a n d a l l t r i a l s o n l y one s u b j e c t (3 y e a r s o l d ) o n o n l y one t r i a l d i d n o t r e s p o n d c o r r e c t l y and n e e d e d t o be r e m i n d e d o f t h e t r u e l o c a t i o n o f t h e t r e a s u r e . A l t h o u g h t h i s s u b j e c t ' s a c t i o n s on t h i s t r i a l h a d t h e e f f e c t o f m i s l e a d i n g t h e o p p o n e n t , t h i s s i n g l e t r i a l was n o t i n c l u d e d i n a n y o f t h e a n a l y s e s . I g n o r a n c e Q u e s t i o n i n H i d e - a n d - S e e k t a s k A d d i t i o n a l l y , p r i o r t o t u r n i n g t o t h e more c e n t r a l i s s u e o f a s s e s s i n g t h e a d e q u a c y o f s u b j e c t s ' r e s p o n s e s t o t h e " f a l s e -b e l i e f " q u e s t i o n s , s u b j e c t s ' p e r f o r m a n c e on t h e more p e r i p h e r a l " i g n o r a n c e q u e s t i o n " w i l l be b r i e f l y e x a m i n e d . S u b j e c t s ' p e r f o r m a n c e on t h e i g n o r a n c e q u e s t i o n i n t h e h i d e - a n d - s e e k t a s k ( i . e . , " W i l l E2 know w h e r e t h e t r e a s u r e i s ? " ) , as c a n b e s e e n i n t a b l e 7, shows an i n c r e a s e i n c o r r e c t r e s p o n s e s w i t h age. I n s e r t t a b l e 7 a b o u t h e r e H i e r a r c h i c a l l o g l i n e a r a n a l y s i s i n d i c a t e s t h a t t h e b e s t f i t t i n g m o d e l f o r t h e s e d a t a i s one i n w h i c h age a n d t a s k p e r f o r m a n c e i n t e r a c t a n d t h a t t h e m o d e l t h a t t h e t w o way e f f e c t o f t h e s e v a r i a b l e s i s z e r o must be r e j e c t e d ( G 2 = 8.725, 2, p <.05). I n l i n e w i t h t h e r e s u l t s f r o m t h e u n e x p e c t e d c h a n g e t a s k , b u t i n c o n t r a s t t o p r e v i o u s r e s u l t s r e p o r t e d by H o g r e f e e t a l . ( 1 9 8 6 ) , c o r r e c t l y a n s w e r i n g t h e i g n o r a n c e q u e s t i o n d i d n o t a p p e a r t o be g e n e r a l l y e a s i e r , e s p e c i a l l y f o r t h e y o u n g e s t s u b j e c t s , t w o o f whom a c t u a l l y f o u n d i t more d i f f i c u l t . T h e s e f i n d i n g s l e a v e c o n s i d e r a b l e room f o r d o u b t a s t o p r e c i s e l y w h a t q u e s t i o n s u c h y o u n g s u b j e c t s u n d e r s t a n d t h e m s e l v e s t o be a n s w e r i n g when a s k e d w h e t h e r E2 w i l l know w h e r e t h e t r e a s u r e i s . G i v e n t h e f a c t t h a t E2 was g e n e r a l l y a l l o w e d more t h a n one a t t e m p t a t f i n d i n g t h e t r e a s u r e on e a c h t r i a l a n d t h a t t h i s q u e s t i o n i s t e m p o r a l l y n o t w e l l m a r k e d i t r e m a i n s a m b i g u o u s how e v e n an a d u l t s h o u l d a n s w e r t h i s q u e s t i o n . F a l s e B e l i e f Q u e s t i o n i n H i d e - a n d - S e e k T a s k I n c o n t r a s t t o t h o s e r e s u l t s o b t a i n e d h e r e a n d e l s e w h e r e w i t h s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e s , 8 0 % o f t h e s u b j e c t s i n t h i s s t u d y r e s p o n d e d c o r r e c t l y t o t h e f a l s e - b e l i e f t e s t q u e s t i o n o f "Where w i l l E2 l o o k ? " when i t was p o s e d i n t h e c o n t e x t o f t h e i r own d e c e p t i v e h i d i n g e f f o r t s . As w i t h t h e h i d i n g r e s p o n s e s , a p p r o x i m a t e l y 2 5 % o f s u b j e c t s ' r e s p o n s e s t o t h i s q u e s t i o n w e r e s c o r e d b y a n i n d e p e n d e n t r a t e r f o r r e l i a b i l i t y w i t h 1 0 0 % a g r e e m e n t o n c e a g a i n b e i n g f o u n d . As c a n be s e e n i n t a b l e 8, 7 0 % o f e v e n t h e y o u n g 3 - y e a r - o l d s s u c c e e d e d i n p r o v i d i n g a " r a t i o n a l " 32 as opposed to a "real i ty" based response to t h i s t es t question Insert table 8 about here on t h e i r best deceptive t r i a l . Logl inear analys is indicates that the model that the two way ef fects of age and task performance are zero cannot be rejected (G 2 = 1.30, 2, p = .53). The best f i t t i n g model i s found for only the one way e f fec t of task performance (G2 = 1.30, 4, p = .86). A more s t r i k i n g way to examine these f indings and how they compare to re su l t s from standard unexpected change measures i s provided by the use of p r e d i c t i o n analyses (VonEye & Brandtstadter, 1988) which compared the f i t of the observed data to two competing models. For comparison purposes the f i r s t of these competing models i s l a b e l l e d the "conceptual d e f i c i t hypothesis" i n response to the strong c la im put f o r t h by Perner et a l . (1987). According to t h i s model c h i l d r e n younger than 3.5 to 4 were sa id to suf fer from some unspeci f ied "cognitive d e f i c i t " which prevents them from understanding the p o s s i b i l i t y of f a l s e - b e l i e f i n others. The second model, re ferred to here as the "conceptual competence  hypothesis". fol lows from the e a r l i e r Chandler, F r i t z and Hala ( in press) study and holds out that subjects who take e f f ec t i ve act ion to dis inform others a c t u a l l y understand that t h e i r deceptive e f for t s w i l l inf luence the b e l i e f s as wel l as the behaviours of t h e i r opponents. The conceptual d e f i c i t hypothesis generates the p r e d i c t i o n that the 3-year-olds i n the present 33 s t u d y m i g h t s u c c e e d i n t h e h i d e - a n d - s e e k t a s k , b u t w o u l d s t i l l f a i l u n e x p e c t e d c h a n g e t a s k s b y f o l l o w i n g r e a l i t y a s s e s s m e n t  s t r a t e g i e s when a s k e d t o p r e d i c t w h e r e t h e i r o p p o n e n t w o u l d a c t u a l l y s e a r c h f o r t h e h i d d e n t r e a s u r e ( s e e t a b l e 9 f o r c e l l p r e d i c t i o n s ) . A somewhat more g e n e r o u s r e a d i n g o f t h i s I n s e r t T a b l e 9 a b o u t h e r e h y p o t h e s i s , b a s e d u p on t h e r e c e n t d e m o n s t r a t i o n t h a t some 3.5-y e a r - o l d s may be c a p a b l e o f u n d e r s t a n d i n g t h e p o s s i b i l i t y o f f a l s e b e l i e f s ( P e r n e r e t a l . 1 9 8 7 ) , w o u l d make t h i s same w i t h h o l d i n g p r e d i c t i o n o n l y f o r y o u n g 3 - y e a r - o l d s . By c o n t r a s t , t h e c o n c e p t u a l c o m p e t e n c e h y p o t h e s i s h o l d s o u t t h a t e v e n c h i l d r e n a s y o u n g a s 3 y e a r s s h o u l d a l r e a d y f o l l o w a r a t i o n a l a s s e s s m e n t s t r a t e g y and p r e d i c t t h a t t h e i r o p p o n e n t w i l l b e l i e v e a n d a c t u pon t h e m i s l e a d i n g c u e s made a v a i l a b l e t o t h e m ( s e e t a b l e 10 f o r c e l l p r e d i c t i o n s ) . I n s e r t t a b l e 10 a b o u t h e r e B e c a u s e b o t h t h e c o n c e p t u a l d e f i c i t h y p o t h e s i s a n d t h e c o n c e p t u a l c o m p e t e n c e m o d e l s p r e d i c t t h a t 4 - y e a r - o l d s w i l l s u c c e e d a t t h i s t a s k , s u b j e c t s i n t h i s age g r o u p w e r e n o t i n c l u d e d i n t h e a n a l y s e s . The e x p e c t e d f r e q u e n c i e s w e r e d i s t r i b u t e d e q u a l l y ( n = 5 i n e a c h c e l l ) , a s age i s n o t f r e e t o v a r y a c r o s s t h e r o w s . A p r e d i c t i o n a n a l y s i s b a s e d u p on t h e s e a n d t h e a c t u a l o b s e r v e d f r e q u e n c i e s r e p o r t e d i n t a b l e 11 f a i l e d t o 34 I n s e r t T a b l e 11 a b o u t h e r e f i n d s t r o n g s u p p o r t f o r t h e c o n c e p t u a l d e f i c i t h y p o t h e s i s ( d e l = - . 4 , p r e c i s i o n = .25, z = - 1 . 0 3 , p ( z ) = . 2 4 ) , i n d i c a t i n g t h a t s u b s c r i b i n g t o t h i s m o d e l d o e s n o t s i g n i f i c a n t l y r e d u c e t h e e r r o r i n t h e o b s e r v e d a s c o m p a r e d t o e x p e c t e d f r e q u e n c y d i s t r i b u t i o n . The c o n c e p t u a l a b i l i t y h y p o t h e s i s , b y c o n t r a s t , r e c e i v e d much s t r o n g e r s u p p o r t ( d e l =.5, p r e c i s i o n = .5, z = 2.24, p ( z ) =.03). The p r e c i s i o n v a l u e a s s o c i a t e d w i t h p r e d i c t i o n s b a s e d u p o n t h i s h y p o t h e s i s , w h i l e r e l a t i v e l y l o w , i s h i g h e r t h a n t h a t o b t a i n e d f o r t h e c o n c e p t u a l d e f i c i t h y p o t h e s i s . When t h e d e l s o f t h e s e t w o c o m p e t i n g h y p o t h e s e s a r e c o m p a r e d i n t e r m s o f t h e i r o v e r a l l p r e d i c t i v e p o wer, t h e d i f f e r e n c e b e t w e e n them was f o u n d t o be s i g n i f i c a n t ( z = 3.83, p<.001) i n d i c a t i n g t h a t t h e c o n c e p t u a l a b i l i t y h y p o t h e s i s i n v o l v e s s i g n i f i c a n t l y more e r r o r r e d u c t i o n t h a n t h e c o n c e p t u a l d e f i c i t h y p o t h e s i s . J u s t i f i c a t i o n s I n a d d i t i o n t o t h e i r a c t u a l p e r f o r m a n c e on t h e u n e x p e c t e d c h a n g e a n d t h e h i d e - a n d - s e e k t a s k s , s u b j e c t s w e r e a s k e d f o r j u s t i f i c a t i o n s o f t h e i r r e s p o n s e s on b o t h t h e s e m e a s u r e s . W h i l e t h e s e j u s t i f i c a t i o n s w e r e s c o r e d d i c h o t o m o u s l y i n b o t h c a s e s , t h e e x a c t n a t u r e o f t h e q u e s t i o n s p o s e d and t h e a p p r o p r i a t e r e s p o n s e s w e r e somewhat d i f f e r e n t i n e a c h t a s k . The U n e x p e c t e d Change T a s k A f t e r m a k i n g t h e i r p r e d i c t i o n s a b o u t w h e r e Sam w o u l d l o o k 35 f o r t h e c a r i n t h e s t a n d a r d u n e x p e c t e d c h a n g e t a s k s u b j e c t s w e re a s k e d "Why w i l l he l o o k t h e r e ? " and a p p r o p r i a t e r e s p o n s e s w e r e h e l d t o be t h o s e t h a t made some r e f e r e n c e t o Sam's l i k e l y a n d l e g i t i m a t e b e l i e f s , o r h i s l a c k o f o p p o r t u n i t y t o h a v e a more up t o d a t e o p i n i o n a s t o t h e c a r ' s new l o c a t i o n . F o r e x a m p l e , i f a s u b j e c t a n s w e r e d " b e c a u s e t h a t ' s w h e r e t h e y p u t t h e c a r " t h e r e s p o n s e was s c o r e d a s c o r r e c t e v e n t h o u g h i t d i d n o t e x p r e s s o t h e r p e r t i n e n t f a c t s , s u c h a s t h a t Sam d i d n o t s e e t h e c a r b e i n g moved. I f , h o w e v e r , s u b j e c t s r e s p o n d e d w i t h o n l y some " d e s i r e " s t a t e m e n t ( e . g . "He w a n t s t o p l a y w i t h t h e c a r " ) , o r s a i d n o t h i n g a t a l l , t h e i r j u s t i f i c a t i o n was s c o r e d a s i n a d e q u a t e . F o r t h i s a n a l y s i s a l l s u b j e c t s w e r e i n c l u d e d and t h o s e t h a t f a i l e d t o c o r r e c t l y a n s w e r t h e f a l s e - b e l i e f t e s t q u e s t i o n n e c e s s a r i l y w e r e s c o r e d a s o f f e r i n g no a d e q u a t e j u s t i f i c a t i o n f o r Sam's f a l s e b e l i e f . The r e s u l t s a s shown i n t a b l e 12 i n d i c a t e t h a t i n t h i s m e a s u r e m e n t c o n t e x t t h e a d e q u a c y o f s u c h j u s t i f i c a t i o n s i n c r e a s e s I n s e r t t a b l e 12 a b o u t h e r e w i t h age. H i e r a r c h i c a l l o g l i n e a r a n a l y s i s r e v e a l s t h a t t h e m o d e l t h a t t h e two way e f f e c t s o f age and a d e q u a t e j u s t i f i c a t i o n o f r e s p o n s e s a r e z e r o i s r e j e c t e d (G2 = 15.38, 2, p. < .001) a n d t h a t a m o d e l i n w h i c h t h e s e t w o v a r i a b l e s i n t e r a c t p r o v i d e s t h e b e s t f i t w i t h t h e d a t a . Much o f t h e r e s p o n s i b i l i t y f o r t h i s s i g n i f i c a n t f i n d i n g i s t r a c e a b l e , h o w e v e r , t o t h e f a c t t h a t m o s t o f t h e y o u n g s u b j e c t s h a d a l r e a d y f a i l e d t o p r e d i c t t h a t Sam's b e l i e f w o u l d be m i s t a k e n and s o c o u l d s c a r c e l y be e x p e c t e d t o 36 j u s t i f y b e l i e f s t h a t t h e y d i d n o t h o l d . The H i d e - a n d - S e e k T a s k A f t e r E2 h a d s e a r c h e d f o r and f a i l e d t o f i n d t h e t r e a s u r e i n t h e h i d e - a n d - s e e k t a s k s u b j e c t s w e re a s k e d t o " T e l l E2 how y o u made i t h a r d f o r h e r t o f i n d t h e t r e a s u r e " . I f s u b j e c t s w e r e a b l e t o e x p l a i n t h e i r a c t i o n s v e r b a l l y o r i f t h e y p h y s i c a l l y d e m o n s t r a t e d t h e i r s t r a t e g y t o E2 t h e y w e r e j u d g e d a s h a v i n g a d e q u a t e l y j u s t i f i e d t h e i r d e c e p t i v e a c t i o n s . As w i t h t h e u n e x p e c t e d c h a n g e t a s k , an a d e q u a t e r e s p o n s e t o t h i s q u e s t i o n was d e p e n d e n t u pon s u b j e c t s h a v i n g f i r s t somehow a c t e d d e c e p t i v e l y . The f r e q u e n c y o f a d e q u a t e j u s t i f i c a t i o n s a c r o s s age g r o u p s i s r e p o r t e d i n t a b l e 13. H i e r a r c h i c a l l o g l i n e a r a n a l y s i s was I n s e r t t a b l e 13 a b o u t h e r e a p p l i e d t o t h e s e d a t a p r o d u c i n g t h e f i n d i n g t h a t t h e m o d e l i n w h i c h t h e two way e f f e c t s o f age a n d p r o p o r t i o n o f a d e q u a t e j u s t i f i c a t i o n s a r e z e r o must b e r e j e c t e d ( G 2 = 6.56, 2, p < .05) and t h a t a m o d e l i n w h i c h t h e s e two v a r i a b l e s i n t e r a c t p r o v i d e s t h e b e s t f i t f o r t h e d a t a . CHAPTER 4: DISCUSSION 37 Deta i l s and Implications of the Research Findings The c e n t r a l question addressed i n t h i s study was whether ch i ldren as young as three years of age do already demonstrate an understanding of the p o s s i b i l i t y of fa l s e b e l i e f , and consequently to possess some r e a l i f f l e d g l i n g theory of mind. The present r e s u l t s c l e a r l y r e p l i c a t e d e a r l i e r f indings reported by Chandler, F r i t z and Hala ( in press) by once again demonstrating that c h i l d r e n as young as three years of age are able to take ac t ive steps to dis inform others about some true state of a f f a i r s , fur ther strengthening the e a r l i e r conclusion that , wel l before t h e i r fourth birthday, such young preschoolers are wel l aware that others are capable of ho ld ing fa l s e b e l i e f s . Nevertheless, these same c h i l d r e n t y p i c a l l y continue to f a i l Wimmer and Perner's unexpected change measure. The d i f f eren t d i f f i c u l t y l eve l s of these two measures was c l e a r l y demonstrated by the fac t that while 90% of the 3-year-olds tested were able to provide s o l i d evidence of t h e i r a b i l i t y to dis inform others, only 20% of t h i s sample would have been judged capable of understanding the p o s s i b i l i t y of fa l s e b e l i e f had they been evaluated using only the Wimmer-Perner measure. This evidence provides stronger support for the conclusion that , contrary to popular opinion, the standard unexpected change measure does not provide a minimally complex method for est imating young c h i l d r e n ' s e a r l i e s t understanding of f a l s e b e l i e f s . Other features of these data also serve to counter various methodologic c r i t i q u e s to which the e a r l i e r Chandler et a l . study remained open. For example, the f indings of t h i s study confirm that the c h i l d r e n who served as subjects i n t h i s study d id not d i f f e r i n any important respect from other samples previous ly administered the unexpected change procedure, thus d i f f u s i n g any argument that the success of subjects here or i n the Chandler, F r i t z and Hala study could be due to having stumbled upon some s p e c i a l l y competent subject sample. S i m i l a r l y , the f i n d i n g that subjects of a l l ages a c t u a l l y remembered where they had hidden the treasure speaks strongly against the p o s s i b i l i t y that they somehow l o s t t rack of the treasure ' s true l oca t ion and thus f a i l e d to understand the contrast between where the treasure was i n fac t and where E2 might mistakenly be l ieve i t to be. Had t h i s study ended with t h i s r e p l i c a t i o n e f f o r t the p o s s i b i l i t y would s t i l l have remained that , despite t h e i r demonstrated e f for t s to dis inform t h e i r opponents, these 3-year-olds only imagined themselves to be manipulating the behaviour, but not the mental states or b e l i e f s of others. That i s , i t might s t i l l have been argued that the deceptive e f for t s of these subjects simply represented some behavioral strategy c a r r i e d out i n t o t a l ignorance of the e f fec t t h e i r actions might have upon the b e l i e f s of t h e i r opponent. It i s for just t h i s reason that the Wimmer-Perner unexpected change measure of f a l s e - b e l i e f understanding has rested i t s case upon c h i l d r e n ' s success or f a i l u r e i n p r e d i c t i n g the search behaviour of an only p a r t i a l l y 39 informed puppet character. The consistent argument has been that only subjects who have already mastered a conception of the p o s s i b i l i t y of f a l s e b e l i e f could anticipate that others w i l l behave i n ways that run contrary to events as they actually are by following courses of action consistent with the misleading information at t h e i r disposal. When applied to children's own apparent attempts to mislead an opponent the f a l s e b e l i e f t e s t question provides a useful check on whether such hiding e f f o r t s are i n f a c t based on some comprehension of other's capacity f o r f a l s e b e l i e f . The f a c t that most of the 3-year-old children i n t h i s study accurately predicted t h e i r opponent's l i k e l y future actions based on the misleading clues that they themselves had l e f t lends strong credence to the claim that t h e i r deceptive actions are based upon an understanding of and an attempt to influence the b e l i e f s of others. Despite the f a c t that between 70 and 90% of the subjects i n a l l age groups tested appropriately responded to questions concerning where t h e i r opponent would search f o r the hidden treasure by i n d i c a t i n g one or more of the locations indicated by the misleading cues they themselves had generated ( i . e . followed what i s referred to here as a " r a t i o n a l assessment strategy"), and did not predict others would search i n the location where the treasure was actually hidden ( i . e . a " r e a l i t y assessment strategy), as would have been the case i f they actually were unaware of the p o s s i b i l i t y of f a l s e b e l i e f s , these findings might 40 be s t i l l be c h a l l e n g e d on t h e g r o u n d s t h a t some o f t h e s e r e s u l t s m i g h t be an a r t i f a c t o f t h e f a c t t h a t i n t h e p r e s e n t a s s e s s m e n t c o n t e x t t h e r e a r e d e c e p t i v e s t r a t e g i e s t h a t p r o v i d e more ways o f b e i n g " r a t i o n a l " t h a n " r e a l i s t i c " . T h a t i s , w h i l e t h e t r e a s u r e i s n a t u r a l l y a l w a y s i n a s i n g l e h i d i n g l o c a t i o n a n d , c o n s e q u e n t l y , t h e r e i s o n l y one r e s p o n s e t h a t c o u l d q u a l i f y a s an i n s t a n c e o f a " r e a l i t y a s s e s s m e n t s t r a t e g y " , t h e same i s n o t t r u e f o r r e s p o n s e s t h a t q u a l i f y a s " r a t i o n a l " . T h i s f o l l o w s b e c a u s e when c h i l d r e n h a v e l e f t d e c e p t i v e c u e s t h a t n o m i n a t e more t h a n one p o s s i b l e h i d i n g l o c a t i o n , p o i n t i n g t o any o r a l l o f t h e s e l o c a t i o n s a s a l i k e l y p l a c e t o s e a r c h i s e q u a l l y " r a t i o n a l " . I n s h o r t , s u c h a l i n e o f a r g u m e n t w o u l d a t t e m p t t o m i n i m i z e t h e s i g n i f i c a n c e o f t h e o b s e r v a t i o n t h a t y o u n g s u b j e c t s s o f r e q u e n t l y f o l l o w e d t h i s r a t i o n a l c o u r s e b y p o i n t i n g t o t h e f a c t t h a t t h e s e r e s u l t s m i g h t be a s i m p l e c o n s e q u e n c e o f t h e r e b e i n g more o p p o r t u n i t y f o r r a n d o m l y g e n e r a t e d r e s p o n s e s t o b e c o d e d a s r a t i o n a l . W h i l e i t i s j u d g e d u n l i k e l y t h a t t h e s u b j e c t s o f t h i s s t u d y w e r e r e s p o n d i n g i n s u c h a random f a s h i o n , a c h e c k on t h i s p o s s i b i l i t y may be h a d b y e x a m i n i n g o n l y t h o s e c a s e s w h e r e s u b j e c t s h a d f a l s e l y n o m i n a t e d a s i n g l e c o n t a i n e r a s t h e l i k e l y h i d i n g p l a c e , e i t h e r b y l a y i n g a s i n g l e s e t o f f a l s e t r a c k s o r b y some o t h e r means s u c h a s m i s a l i g n i n g o n l y one o f t h e empty c o n t a i n e r s . L o o k i n g a t e v e r y i n s t a n c e o f s u c h a s i n g l e f a l s e l y n o m i n a t e d c o n t a i n e r a c r o s s a l l s u b j e c t s and a l l t r i a l s , a t o t a l o f 23 s u c h o c c u r r e n c e s w e re f o u n d . Of t h e s e , 7 8 % o f t h e r e s p o n s e s g i v e n w e r e r a t i o n a l a s s e s s m e n t s t r a t e g i e s . Among t h e four 3-year-olds who used such a s i n g l e - f a l s e - t r a c k strategy 75% (3) s i m i l a r l y answered with a r a t i o n a l assessment strategy, i n d i c a t i n g that E2 would look only i n the container marked by the t racks . C l e a r l y then, even when the p o s s i b i l i t y of a correc t response by chance i s maximally reduced, these young subjects continued to act i n ways that suggest that t h e i r opponent would be led by ava i lab le evidence to bel ieve something which they themselves knew to be f a l s e . A second argument that might be l e v e l l e d against the c la im put f o r t h here that subjects' "rat ional responses" indicate an underlying concept of f a l s e - b e l i e f understanding i s that when subjects were asked where E2 would look they simply mis interpreted such questions as something l i k e "Where do the tracks lead?". A counter to t h i s argument can be provided by an examination of only those cases where subjects took steps to e l iminate a l l t e l l - t a l e t racks . While the h id ing strategy of leaving no tracks does not qua l i fy as unambiguously deceptive i n the scor ing typology used here, such a strategy does provide an opportunity to observe how subjects proceed i n the absence of perceptual clues ( i . e . f o o t p r i n t s ) . That i s , i f i t i s to be argued that the subjects of t h i s study succeeded i n answering "belief" questions simply by not ing where the ava i lab le tracks l ed , then any subjects using such a p r i m i t i v e strategy should f a i l to respond i n a seemingly "rat ional" way whenever a l l such cues were missing. As a t e s t of t h i s p o s s i b i l i t y a l l of the responses of subjects that resu l ted i n the p lay ing surface being 42 l e f t empty o f t r a c k s was e x a m i n e d s e p a r a t e l y . Of t h e 24 h i d i n g e f f o r t s t h a t met t h i s c r i t e r i o n 7 9 % r e s u l t e d i n p r e d i c t i o n s i n d i c a t i n g t h a t E2 w o u l d n e e d t o l o o k i n a l l o f t h e c o n t a i n e r s , o r i n some s i n g l e f a l s e c o n t a i n e r b e c a u s e t h e s u b j e c t w o u l d t e l l h e r t o do s o . S u c h a p p r o p r i a t e r e s p o n s e s s p e a k a g a i n s t a n y s u g g e s t i o n t h a t s u b j e c t s s i m p l y b a s e d t h e i r p r e d i c t i o n s u p o n t h e a v a i l a b i l i t y o f t h e p e r c e p t u a l c u e s p r o v i d e d b y v a r i o u s f a l s e t r a i l s . T a k e n t o g e t h e r , a l l o f t h e s e f i n d i n g s a r e s e e n t o p r o v i d e s t r o n g e v i d e n c e i n s u p p o r t o f t h e c o n c l u s i o n t h a t e v e n y o u n g 3-y e a r - o l d s a l r e a d y u n d e r s t a n d t h e p o s s i b i l i t y o f f a l s e b e l i e f a n d c o n s e q u e n t l y a l r e a d y p o s s e s s some f l e d g l i n g t h e o r y o f m i n d . L i m i t a t i o n s a n d S u g g e s t i o n s f o r F u t u r e R e s e a r c h D e s p i t e t h e c l e a r a b i l i t i e s shown b y t h e y o u n g e s t s u b j e c t s o f t h i s s t u d y numerous q u e s t i o n s r e m a i n a b o u t j u s t w h a t s p e c i f i c f e a t u r e s o f t h e u n e x p e c t e d c h a n g e t a s k p r e v e n t 3 - y e a r - o l d s f r o m a d e q u a t e l y d e m o n s t r a t i n g t h e i r a b i l i t y i n t h a t m e a s u r e m e n t c o n t e x t . As o u t l i n e d e a r l i e r , some o f t h e d i f f i c u l t i e s y o u n g p e r s o n s e x p e r i e n c e w i t h u n e x p e c t e d c h a n g e m e a s u r e s o f f a l s e b e l i e f may s i m p l y r e f l e c t t h e f a c t t h a t t h e s e p r o c e d u r e s a r e age i n a p p r o p r i a t e o r u n n e c e s s a r i l y c o m p l e x . I n t h e u n e x p e c t e d c h a n g e t a s k , f o r e x a m p l e , s u b j e c t s a r e p a s s i v e o b s e r v e r s who must p r o c e s s , c o m p r e h e n d and remember a c o m p l e x s e t o f c o n d i t i o n s t h a t a f f e c t a s t o r y c h a r a c t e r ' s a c c e s s t o r e l e v a n t i n f o r m a t i o n . I n c o n t r a s t , i n t h e d e c e p t i o n t a s k s u b j e c t s a r e a c t i v e p a r t i c i p a n t s who i n v e n t t h e i r own manner o f i n s t i l l i n g f a l s e b e l i e f s i n a n o t h e r . W h i l e s u c h p r o c e d u r a l d i f f e r e n c e s m i g h t p r o v i d e a s u f f i c i e n t e x p l a n a t i o n f o r t h e d i f f e r e n t r e s u l t s p r o v i d e d b y t h e s e t w o t a s k s , t h i s c o n c l u s i o n must a w a i t an e m p i r i c a l d e m o n s t r a t i o n . A n o t h e r q u e s t i o n t h a t t h i s s t u d y d o e s n o t a d d r e s s i s w h a t m i g h t be c o n s i d e r e d t h e l o w e r age b o u n d a r y o f p o s s e s s i n g a r u d i m e n t a r y t h e o r y o f m i n d . I n t h i s s t u d y y o u n g 3 - y e a r - o l d c h i l d r e n w e r e shown t o be q u i t e c a p a b l e , n o t o n l y o f a t t e m p t i n g t o d e c e i v e a n o t h e r b u t o f b e i n g a b l e t o comment u p o n w h a t t h e d e c e i v e d o t h e r w o u l d a c t u a l l y b e l i e v e . W h i l e c h i l d r e n y o u n g e r t h a n 3 y e a r s w e r e n o t i n c l u d e d h e r e , C h a n d l e r e t a l . f o u n d t h a t e v e n 2 1 / 2 - y e a r - o l d c h i l d r e n t y p i c a l l y a t t e m p t e d t o d e c e i v e t h e o t h e r s i n t h e same h i d e - a n d - s e e k game. T h e s e y o u n g s u b j e c t s w e r e n o t a s k e d s p e c i f i c a l l y a b o u t t h e l i k e l y f a l s e b e l i e f s o f t h e i r o p p o n e n t , h o w e v e r , and g i v e n t h a t 2 1 / 2 - y e a r - o l d c h i l d r e n h a v e v e r y l i m i t e d v e r b a l a b i l i t i e s i t i s p o s s i b l e t h a t t h e s e y o u n g e s t s u b j e c t s c o u l d n o t h a v e a d e q u a t e l y a n s w e r e d t h e f a l s e - b e l i e f q u e s t i o n , d e s p i t e t h e i r o f t e n s u c c e s s f u l h i d i n g e f f o r t s . I t w o u l d be i m p r u d e n t h o w e v e r t o c o n c l u d e t h a t s u c h a f a i l u r e w o u l d n e c e s s a r i l y r u l e o u t a n e m e r g i n g u n d e r s t a n d i n g o f f a l s e b e l i e f . I n s t e a d , s u c h f a i l u r e c o u l d s i m p l y i n d i c a t e t h a t c h i l d r e n u n d e r t h e age o f 3 y e a r s a r e u n a b l e t o e f f e c t i v e l y f o l l o w s u c h c o m p l e x q u e s t i o n s o r l a c k t h e a b i l i t y t o comment u p o n t h e f a l s e b e l i e f s o f o t h e r s , d e s p i t e t h e i r a b i l i t y t o u t i l i z e s u c h k n o w l e d g e i n t h e i r i n t e r p e r s o n a l i n t e r a c t i o n s . To tap the lower age boundary of t h i s a b i l i t y i t may be necessary to look beyond even the present deception measure and to turn to an examination of the spontaneous attempts of toddlers to deceive others i n everyday s o c i a l settings. While n a t u r a l i s t i c observations of t h i s sort are l i k e l y to underestimate the presence of such deceptive actions, due to t h e i r r e l a t i v e l y infrequent nature, i t may be possible to access such actions through the use of various diary methods. Over and above any future attempts to better e s t a b l i s h the lower age boundary of young children's f i r s t theories of mind, there remain numerous i n t e r e s t i n g and unanswered questions concerning the l i k e l y additional steps that young persons pass through i n eventually a r r i v i n g at an a d u l t - l i k e theory of mind. Studies aimed at better understanding t h i s process are a necessary part of any agenda aimed at achieving an adequate understanding of children's developing theories of mind. 45 REFERENCES Anderson, M. (1986). C u l t u r a l c o n c a t e n a t i o n of d e c e i t and secrecy. In R. W. M i t c h e l l , and N. S. 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( 4 ) , 4 5 6 - 4 7 1 . S o r d a h l , T. A. ( 1 9 8 6 ) . E v o l u t i o n a r y a s p e c t s o f a v i a n d i s t r a c t i o n d i s p l a y : V a r i a t i o n i n A m e r i c a n a v o c e t a n d b l a c k - n e c k e d s t i l t a n t i p r e d a t o r b e h a v i o u r . I n R. W. M i t c h e l l & N. S. Thompson ( E d s . ) , D e c e p t i o n : P e r s p e c t i v e s o n human a n d nonhuman  d e c e i t ( p p . 8 7 - 1 1 2 ) . A l b a n y : S t a t e U n i v e r s i t y o f New Y o r k P r e s s . S t e i n , N. L. & L e v i n e , L. J . ( 1 9 8 5 ) . The o r g a n i z a t i o n a n d d e v e l o p m e n t o f c h i l d r e n ' s k n o w l e d g e a b o u t t h r e e e m o t i o n a l s t a t e s . T a y l o r , M. & F l a v e l l , J . H. ( 1 9 8 4 ) . S e e i n g a n d b e l i e v i n g : C h i l d r e n ' s u n d e r s t a n d i n g o f t h e d i s t i n c t i o n b e t w e e n a p p e a r a n c e a nd r e a l i t y . C h i l d D e v e l o p m e n t . 55. 1710-1720. V a s e k , M. E. ( 1 9 8 6 ) . L y i n g a s a s k i l l : The d e v e l o p m e n t o f d e c e p t i o n i n c h i l d r e n . I n R. W. M i t c h e l l & N. S. Thompson ( E d s . ) , D e c e p t i o n : P e r s p e c t i v e s o n human a n d nonhuman  d e c e i t ( p p . 2 7 1 - 2 9 2 ) . A l b a n y : S t a t e U n i v e r s i t y o f New Y o r k P r e s s . v o n E y e , A. & B r a n d s t a d t e r , J . ( 1 9 8 8 ) . E v a l u a t i n g d e v e l o p m e n t a l h y p o t h e s e s u s i n g s t a t e m e n t c a l c u l u s a n d n o n p a r a m e t r i c s t a t i s t i c s . I n P. B. B a l t e s , D. L. F e a t h e r m a n , & R. M. L e r n e r ( E d s . ) , L i f e - s p a n d e v e l o p m e n t a n d b e h a v i o u r ( V o l . 8 ) , (p p . 6 1 - 9 7 ) . H i l l s d a l e , N J : L a w r e n c e E r l b a u m . W e l l m a n , H. M. ( 1 9 8 5 ) . The c h i l d ' s t h e o r y o f m i n d : The d e v e l o p m e n t o f c o n c e p t s o f c o g n i t i o n . I n S. R. Y u s s e n ( E d . ) , The g r o w t h o f r e f l e c t i o n ( p p . 1 6 9 - 2 0 6 ) . S a n D i e g o : A c a d e m i c P r e s s . W e l l m a n , H. M. ( 1 9 8 8 ) . F i r s t s t e p s i n t h e c h i l d ' s t h e o r i z i n g a b o u t t h e m i n d . I n J . W. A s t i n g t o n , P. L. H a r r i s , a n d D. R. O l s o n ( E d s . ) , D e v e l o p i n g t h e o r i e s o f m i n d ( p p . 6 4 - 9 2 ) . New Y o r k : C a m b r i d g e U n i v e r s i t y P r e s s . W e l l m a n , H. M. ( i n p r e s s ) . C h i l d r e n ' s e a r l y t h e o r i e s o f m i n d . B r a d f o r d B o o k s . W e l l m a n , H. M. & B a r t s c h , K. ( i n p r e s s ) . Y o u n g c h i l d r e n ' s r e a s o n i n g a b o u t b e l i e f s . C o g n i t i o n . W e l l m a n , H. M. & E s t e s , D. ( 1 9 8 6 ) . E a r l y u n d e r s t a n d i n g o f m e n t a l e n t i t i e s : A r e e x a m i n a t i o n o f c h i l d h o o d r e a l i s m . C h i l d D e v e l o p m e n t . 57, 910-923. Wimmer, H., G r u b e r , S. & P e r n e r , J . ( 1 9 8 4 ) . Y o u n g c h i l d r e n ' s c o n c e p t i o n o f l y i n g : L e x i c a l r e a l i s m - m o r a l s u b j e c t i v i s m . J o u r n a l o f E x p e r i m e n t a l C h i l d P s y c h o l o g y . 37. 1-30. Wimmer, H., G r u b e r , S. & P e r n e r , J . ( 1 9 8 5 ) . Y o u n g c h i l d r e n ' s c o n c e p t i o n o f l y i n g : M o r a l i n t e n t i o n a n d t h e d e n o t a t i o n a n d c o n n o t a t i o n o f " t o l i e " . D e v e l o p m e n t a l P s y c h o l o g y . 2 1 , 9 9 3 -995. Wimmer, H., & P e r n e r , J . ( 1 9 8 3 ) . B e l i e f s a b o u t b e l i e f s : R e p r e s e n t a t i o n a n d c o n s t r a i n i n g f u n c t i o n o f w r o n g b e l i e f s i n 54 y o u n g c h i l d r e n ' s u n d e r s t a n d i n g o f d e c e p t i o n . C o g n i t i o n . 13, 103-128. 55 TABLES T a b l e 1 H i d i n g S t r a t e g i e s b y Age 56 H i d i n g S t r a t e g y 1  3.0 y r s Age a 3.5 y r s 4.0 y r s W i t h h o l d i n g T a m p e r i n g 0 1 1 0 0 0 L y i n g D i s i n f o r m i n g D i s i n f o r m i n g p l u s T a m p e r i n g 0 6 3 1 2 6 2 3 5 a n = 10 e a c h age g r o u p 57 Table 2 Presence or Absence of Deceptive Strategy by Age Hiding Strategy 3. . 0 yrs Age a 3.5 yrs 4.0 yrs Non-Deceptive 1 1 0 Deceptive 9 9 10 Note. Non-deceptive strategy included simple withholding and wiping up tracks . Deceptive strategy included l y i n g i n conjunction with other strategy, prov id ing fa l s e c lues , prov id ing f a l s e clues and destroying actual evidence. a n = 10 each age group T a b l e 3 P e r f o r m a n c e on I g n o r a n c e Q u e s t i o n i n U n e x p e c t e d Change T a s k b y Age Age a I g n o r a n c e q u e s t i o n 3.0 y r s 3.5 y r s 4.0 y r s F a i l 9 3 0 P a s s 1 7 10 a n = 10 e a c h age g r o u p T a b l e 4 P e r f o r m a n c e on F a l s e B e l i e f Q u e s t i o n i n U n e x p e c t e d Change T a s k b y Age Age a F a l s e B e l i e f q u e s t i o n 3.0 y r s 3.5 y r s 4.0 y r s F a i l 8 3 1 P a s s 2 7 9 a n = 10 e a c h age g r o u p T a b l e 5 I g n o r a n c e b y F a l s e B e l i e f i n U n e x p e c t e d Change T a s k I g n o r a n c e Q u e s t i o n F a l s e B e l i e f q u e s t i o n F a i l P a s s F a i l 6 1 P a s s 1 22 McNemar (N = 3 0 ) , p. = 1.0 T a b l e 6 W i t h i n S u b . i e c t C o m p a r i s o n  o f H i d e - a n d - S e e k a n d U n e x p e c t e d Change T a s k s D e c e p t i o n F a l s e B e l i e f T a s k No Y e s F a i l 2 10 P a s s 0 18 McNemar (N = 3 0 ) , p < 0.1 Table 7 Performance on Ignorance Question i n Hide-and-Seek Task by Age Age a Ignorance question 3.0 yrs 3.5 yrs 4.0 yrs F a i l 5 2 0 Pass 5 8 10 a n = 10 each age group T a b l e 8 P e r f o r m a n c e on F a l s e B e l i e f Q u e s t i o n i n H i d e -•and-Seek T a s k by Age Age a S t r a t e g y 3.0 y r s 3.5 y r s 4. . 0 y r s R e a l i t y A s s e s s m e n t 3 2 1 R a t i o n a l A s s e s s m e n t 7 8 9 a n = 10 e a c h age g r o u p T a b l e 9 P r e d i c t e d C e l l s f o r C o n c e p t u a l D e f i c i t H y p o t h e s i s R e a l i t y R a t i o n a l Age a A s s e s s m e n t A s s e s s m e n t 3.0 y r s Pb NF* 3.5 y r s P P 4.0 y r s NP P a n = 10 e a c h age g r o u p b P = P e r m i t t e d C e l l s c NP = N o n - p e r m i t t e d C e l l s T a b l e 10 P r e d i c t e d C e l l s f o r C o n c e p t u a l C o m p e t e n c e H y p o t h e s i s R e a l i t y R a t i o n a l Age a A s s e s s m e n t A s s e s s m e n t 3.0 y r s NP<= Pb 3.5 y r s NP P 4.0 y r s NP P a n = 10 e a c h age g r o u p b P = P e r m i t t e d C e l l s c NP = N o n - p e r m i t t e d C e l l s T a b l e 11 O b s e r v e d F r e q u e n c i e s f o r F a l s e B e l i e f Q u e s t i o n  i n H i d e - a n d - S e e k T a s k R e s p o n s e t o F a l s e B e l i e f t e s t q u e s t i o n R e a l i t y R a t i o n a l A ge a A s s e s s m e n t A s s e s s m e n t 3.0 y r s 3 7 3.5 y r s 2 8 a n = 10 e a c h age g r o u p T a b l e 12 J u s t i f i c a t i o n o f R e s p o n s e s  on U n e x p e c t e d Change T a s k b y Age Age a J u s t i f i c a t i o n 3.0 y r s 3.5 y r s 4.0 y r s No 10 4 3 Y e s 0 6 7 a n = 10 e a c h age g r o u p T a b l e 13 J u s t i f i c a t i o n o f R e s p o n s e s o n H i d e - a n d - S e e k T a s k b y Age Age a J u s t i f i c a t i o n 3.0 y r s 3.5 y r s 4.0 y r s No 4 2 2 Y e s 6 8 8 a n = 10 e a c h age g r o u p 69 FIGURES FIGURE 1 E x p e r i m e n t a l S e t u p f o r U n e x p e c t e d Change P r o c e d u r e FIGURE 2 E x p e r i m e n t a l S e t u p f o r H i d e - a n d - S e e k P r o c e d u r e 73 74 FIGURE 3 Comparison of Performance Between Unexpected Change Task and Hide-and-Seek Task 75" Figure 3 Comparison of Performance Between Unexpected Change Task and Hide-and-Seek Task 1 0 0 76 APPENDICES APPENDIX A 77 REVIEW OF THE LITERATURE E v i d e n c e S u p p o r t i n g E a r l y - V e r s u s L a t e - O n s e t P o s i t i o n s The E a r l y - O n s e t V i e w A c c o r d i n g t o t h e e a r l y o n s e t v i e w t h e r e a r e c o n v e r g i n g l i n e s o f e v i d e n c e , a l l o f w h i c h s u g g e s t c h i l d r e n c o n s i d e r a b l y y o u n g e r t h a n 4 y e a r s o f age a l r e a d y show e v i d e n c e o f p o s s e s s i n g a r u d i m e n t a r y i n t e n t i o n a l - s t a t e p s y c h o l o g y o r t h e o r y o f m i n d ( e . g . W e l l m a n , 1 9 8 5 ) . From t h i s p e r s p e c t i v e i n t e r l o c k i n g l i n e s o f e v i d e n c e a r e s e e n t o c o n v e r g e w h i c h s u g g e s t t h a t c h i l d r e n a s y o u n g a s 2 o r 2 1/2 y e a r s u n d e r s t a n d t h e d i s t i n c t i o n b e t w e e n b e l i e f s a nd t h e r e a l w o r l d e v e n t s t o w h i c h t h o s e b e l i e f s r e f e r . One l i n e o f e v i d e n c e i n s u p p o r t o f t h i s e a r l y - o n s e t v i e w comes f r o m t h e l i t e r a t u r e c o n c e r n i n g y o u n g c h i l d r e n ' s a b i l i t i e s t o e n g a g e i n a c t s o f p r e t e n s e . A c c o r d i n g t o L e s l i e ( 1 9 8 2 ; 1988) p r e t e n d p l a y r e q u i r e s n o t o n l y a r e p r e s e n t a t i o n o f t h e w o r l d a s i t i s , b u t a l s o a m e t a r e p r e s e n t a t i o n o f t h e s e same e v e n t s t h a t a l l o w s f o r a " d e c o u p l i n g " o f s u c h p r i m a r y r e p r e s e n t a t i o n s f r o m t h e i r n o r m a l r e f e r e n t s . From t h i s p e r s p e c t i v e t h e e m e r g e n c e o f p r e t e n d p l a y c o n s t i t u t e s a d r a m a t i c s h i f t i n t h e c h i l d ' s m e t a r e p r e s e n t a t i o n a l a b i l i t i e s ( M c C u n e - N i c o l i c h , 1981) o f t h e s o r t u s u a l l y a s s o c i a t e d w i t h t h e e m e r g e n c e o f some e a r l y t h e o r y o f m i n d . W h i l e t h e f i r s t s u c h p r e t e n d g e s t u r e s emerge a r o u n d 12 months o f age, a l i t e r a t u r e r e v i e w c a r r i e d o u t b y F e i n ( 1 9 8 1 ) 78 s u g g e s t s t h a t t h e s e a l t e r n a t i v e r e p r e s e n t a t i o n s o f r e a l i t y c o n t i n u e t o b e p r i v a t e a n d i d i o s y n c r a t i c u n t i l some t i m e a r o u n d 15 t o 20 months. I t i s t h i s e m e r g e n c e o f s o c i a l p r e t e n d p l a y t h a t a p p e a r s t o mark t h e d e v e l o p m e n t a l p l a c e a t w h i c h c h i l d r e n f i r s t come t o u n d e r s t a n d t h a t o t h e r s c a n r e p r e s e n t r e p r e s e n t a t i o n s , t h u s l a y i n g t h e g r o u n d w o r k f o r t h e e m e r g e n c e o f a f l e d g l i n g t h e o r y o f m i n d . T h a t i s , w h i l e n o n - s o c i a l p r e t e n s e w o u l d a p p e a r t o r e q u i r e some m e t a r e p r e s e n t a t i o n s ( L e s l i e , 1 9 8 8 ) , s o c i a l p r e t e n d p l a y w o u l d seem t o n e c e s s a r i l y r e q u i r e t h e a b i l i t y b o t h t o h o l d t o s u c h a m e t a r e p r e s e n t a t i o n a n d a l s o t o c l e a r l y u n d e r s t a n d t h a t s u c h a m e t a r e p r e s e n t a t i o n i s s i m u l t a n e o u s l y h e l d b y o t h e r s . D e p e n d i n g upon t h e c o n t e x t , s o c i a l p r e t e n d p l a y h a s b e e n d e m o n s t r a t e d t o be a p a r t o f t h e r e p e r t o i r e o f c h i l d r e n a s y o u n g as 2 y e a r s o f age. L u c a r i e l l o ( 1 9 8 7 ) , f o r e x a m p l e , f o u n d t h a t i n a f a m i l i a r p l a y c o n t e x t 24 t o 29 month- o l d s i n i t i a t e d p r e t e n d p l a y w i t h t h e i r m o t h e r s . S i m i l a r l y , i n a n a t u r a l i s t i c c o n t e x t i n v o l v i n g p r e s c h o o l p e e r s , Howes ( 1 9 8 5 ) f o u n d t h a t a l l c h i l d r e n o v e r 30 m o n t h s , 6 7 % a t 27-28 months a n d 5 0 % a t 21-23 months e n g a g e d i n c o o p e r a t i v e s o c i a l p r e t e n d p l a y . Dunn a n d D a l e ( 1 9 8 4 ) a l s o f o u n d t h a t i n s i b l i n g i n t e r a c t i o n 2 - y e a r o l d s a n d e v e n some 18-month o l d s s h a r e d i n p r e t e n d games w i t h o l d e r s i b l i n g s . C l e a r l y t h e n , b y a r o u n d 2 t o 3 y e a r s o f age c h i l d r e n seem c a p a b l e o f e n g a g i n g i n p r e t e n d p l a y w i t h a n o t h e r t h u s d e m o n s t r a t i n g t h e i r a b i l i t y t o r e p r e s e n t t h a t t h e o t h e r was a l s o p r e t e n d i n g . A s e c o n d l i n e o f e v i d e n c e i n s u p p o r t o f t h e c l a i m t h a t c h i l d r e n y o u n g e r t h a n 4 y e a r s o f age a l r e a d y p o s s e s s some i n i t i a l t h e o r y o f m i n d i s p r o v i d e d b y s t u d i e s i n t o c h i l d r e n ' s s p o n t a n e o u s u s e o f m e n t a l s t a t e t e r m s . A t a r o u n d 2 1/2 y e a r s , f o r e x a m p l e , c h i l d r e n h a v e b e e n shown t o s p o n t a n e o u s l y e m p l o y a v a r i e t y o f m e n t a l s t a t e v e r b s s u c h a s t h i n k , remember, know, w i s h , hope a n d w ant ( B r e t h e r t o n 1984; B r e t h e r t o n & B e e g h l y , 1982; B r e t h e r t o n , McNew & B e e g h l y - S r a i t h , 1981; S h a t z , W e l l m a n a n d S i l b e r , 1983; W e l l m a n 1 9 8 5 ) . R e f e r e n c i n g s u c h e v i d e n c e , B r e t h e r t o n and B e e g h l y ( 1 9 8 2 ) h a v e a r g u e d t h a t h a v i n g some b e g i n n i n g t h e o r y o f m i n d i s an e s s e n t i a l p r e r e q u i s i t e f o r b e i n g a b l e t o e x p r e s s a k n o w l e d g e o f i n t e r n a l s t a t e s . W h i l e s i m p l y p a r r o t i n g s u c h i n t e n t i o n a l s t a t e t e r m s o b v i o u s l y i s i n s u f f i c i e n t e v i d e n c e f o r c o n c l u d i n g t h e p r e s e n c e o f a t h e o r y o f m i n d , t h e r e a l s o i s e v i d e n c e t h a t s t r o n g l y s u g g e s t s t h e s e c h i l d r e n h a v e a b a s i c i f n o t f u l l y e l a b o r a t e d g r a s p o f t h e c o n v e n t i o n a l m e a n i n g o f t h e s e t e r m s . I n a l o n g i t u d i n a l s t u d y o f t h e n a t u r a l l y o c c u r r i n g s p e e c h o f c h i l d r e n a g e d 2 t o 3 1/2 Hood and B l o o m ( 1 9 7 9 ) , f o r e x a m p l e , f o u n d t h a t t h e i r y o u n g s u b j e c t s made f r e q u e n t a n d a p p r o p r i a t e r e f e r e n c e s t o p s y c h o l o g i c a l c a u s a t i o n . S i m i l a r l y , J o h n s o n and W e l l m a n ( 1 9 8 0 ) h a v e d e m o n s t r a t e d t h a t t h e i r 2 1/2 t o 3 - y e a r o l d s b r a c k e t t o g e t h e r s u c h m e n t a l t e r m s and u n d e r s t a n d them as b e l o n g i n g t o c a t e g o r i e s d i f f e r e n t f r o m t h e a c t i o n s a n d e v e n t s t o w h i c h t h e y r e f e r . F u r t h e r e v i d e n c e a g a i n s t t h e p o s s i b i l i t y t h a t s u c h y o u n g c h i l d r e n s i m p l y p a r r o t m e n t a l t e r m s comes f r o m W e l l m a n ( 1 9 8 5 ) and S h a t z , W e l l m a n and S i l b e r ( 1 9 8 3 ) who f o u n d t h a t b y a r o u n d 2 80 1/2 y e a r s c h i l d r e n seem t o u s e a t l e a s t t h e more s a l i e n t o f t h e s e m e n t a l s t a t e v e r b s i n c o n t r a s t i v e ways t h a t c l e a r l y d i s t i n g u i s h t h e m f r o m t h e i r e x t e r n a l r e f e r e n t s . I n a more r e c e n t s t u d y W e l l m a n and E s t e s ( 1 9 8 6 ) f o u n d t h a t t h e m a j o r i t y o f 3 y e a r o l d s u b j e c t s c o u l d c o r r e c t l y a n s w e r q u e s t i o n s c o n c e r n i n g c r i t e r i a f o r d i s t i n g u i s h i n g m e n t a l and n o n m e n t a l e v e n t s and made v e r y f e w e r r o r s when s o r t i n g r e a l a nd n o n r e a l e v e n t s . T h e s e f i n d i n g s t a k e n t o g e t h e r s t r o n g l y s u g g e s t t h a t b y t h r e e y e a r s o f age c h i l d r e n c a n u n d e r s t a n d n o t o n l y t h a t a m e n t a l w o r l d e x i s t s a p a r t f r o m r e a l i t y , b u t a l s o t h a t t h e b e l i e f s t h a t p o p u l a t e t h e i r w o r l d h a v e no c o u n t e r p a r t i n , o r o t h e r w i s e d i v e r g e f r o m , t h i n g s a s t h e y a c t u a l l y a r e . R e l a t e d r e s e a r c h i n t o c h i l d r e n ' s u n d e r s t a n d i n g o f t h e i r own a n d o t h e r s ' e m o t i o n a l l i v e s makes a s i m i l a r p o i n t a n d i n d i c a t e s t h a t e v e n v e r y y o u n g p r e s c h o o l e r s make a p p r o p r i a t e c o n n e c t i o n s b e t w e e n v a r i o u s m e n t a l e n t i t i e s a n d t h e a f f e c t i v e l y c h a r g e d a c t i o n s t o w h i c h t h e y a r e l i n k e d . S t e i n and L e v i n e ( 1 9 8 5 ) , f o r e x a m p l e , f o u n d t h a t 3 - y e a r o l d s a r e a b l e t o a n t i c i p a t e t h e a p p r o p r i a t e e m o t i o n a l r e s p o n s e s c a l l e d f o r when e i t h e r a m a t c h o r m i s m a t c h o c c u r s b e t w e e n someone's d e s i r e s a n d t h e a c t u a l o u t c o m e s t h a t e n s u e . S i m i l a r l y , P o u l i n - D u b o i s and S h u l t z ( 1 9 8 8 ) f o u n d t h a t b y 2 1/2 t o 3 y e a r s o f age c h i l d r e n w e r e a b l e t o a t t r i b u t e i n t e n t i o n t o o t h e r s and t o v i e w v a r i o u s a c t i o n s i n r e l a t i o n t o t h e i n t e n t i o n s t h a t p r o m p t them. T h a t p r e s c h o o l c h i l d r e n r e a d i l y make s u c h c o n n e c t i o n s s t r o n g l y s u g g e s t s t h a t t h e i r u s e o f m e n t a l t e r m s g o e s b e y o n d mere m o u t h i n g o f t h e w o r d s a n d a g a i n i m p l i e s a 81 b a s i c u n d e r s t a n d i n g o f how s u c h m e n t a l e n t i t i e s m i g h t a f f e c t a c t i o n s . V e r y y o u n g c h i l d r e n h a v e a l s o d e m o n s t r a t e d t h a t t h e y h a v e some c o n c e p t i o n o f j u s t w h ere m e n t a l e n t i t i e s o r i g i n a t e f r o m a n d some b a s i c n o t i o n s o f how t h e y a r e g o v e r n e d . I n a s t u d y o f c h i l d r e n ' s u n d e r s t a n d i n g o f t h e b r a i n a n d t h e m i n d ( J o h n s o n & W e l l m a n , 1982) 3 - y e a r o l d s , a l t h o u g h somewhat i n c o n s i s t e n t , w e r e f o u n d , f o r e x a m p l e , t o t r e a t t h e b r a i n v e r y much l i k e t h e m i n d i n t h a t t h e b r a i n was s e e n t o c o n t r o l m e n t a l p r o c e s s e s b u t n o t o t h e r p h y s i c a l p r o c e s s e s . T h a t i s , t h e s e y o u n g c h i l d r e n saw t h e b r a i n a n d b y a s s o c i a t i o n t h e m i n d a n d m e n t a l e n t i t i e s a s s o m e t h i n g d i s t i n c t f r o m b e h a v i o r s a nd r e s p o n s i b l e f o r m e n t a l a c t i o n s s u c h as t h i n k i n g , d r e a m i n g , a nd r e m e m b e r i n g . W h i l e t h i s c o n c e p t o f b r a i n a n d m i n d i s l i m i t e d , i t d o e s show e v i d e n c e f o r some t h e o r y - l i k e u n d e r s t a n d i n g o f w h a t a m i n d i s and w h a t i t m i g h t c o n t r o l . On t h e b a s i s o f a l l t h e s t u d i e s c i t e d a b o v e , i t seems c l e a r t h a t b y 2 1/2 t o 3 y e a r s o f age c h i l d r e n a l r e a d y h a v e some a c c e s s t o and k n o w l e d g e o f t h e w o r k i n g s o f t h e m e n t a l w o r l d , a n d u n d e r s t a n d t h i s m e n t a l d o m a i n n o t o n l y a s d i s t i n c t f r o m t h e e x t e r n a l w o r l d , b u t a l s o a s a d e t e r m i n a n t o f t h e a c t i o n , t h o u g h t s a n d e m o t i o n s o f o t h e r s . A t h i r d m a j o r s o u r c e o f e v i d e n c e i n s u p p o r t o f t h e e a r l y e m e r g e n c e o f c h i l d r e n ' s t h e o r i e s o f m i n d d e r i v e s f r o m r e s e a r c h i n t o v i s u a l p e r s p e c t i v e t a k i n g a b i l i t i e s . I n r e s p o n s e t o P i a g e t ' s a s s e r t i o n t h a t p r e s c h o o l c h i l d r e n r e m a i n u n a b l e t o 82 understand that others may view the same object d i f f e r e n t l y (Piaget & Inhelder, 1969), F l a v e l l (1978) proposed that there i s i n fact more than one l e v e l of perspective taking , and that the f i r s t of these l eve l s i s achieved a great deal e a r l i e r than Piaget proposed. F l a v e l l maintains that at l e v e l 1 c h i l d r e n f i r s t come to understand that i f another's v i s u a l access to an object or event i s r e s t r i c t e d or obscured i n any way, then that other w i l l not see the object . The l i m i t a t i o n of t h i s l e v e l 1 a b i l i t y , according to F l a v e l l , i s that although young 2- and 3-year o ld c h i l d r e n seem capable of determining what another may or may not see, i t i s not u n t i l they are 4 or more that they achieve the l e v e l 2 a b i l i t y to understand how others may d i f f e r e n t l y construe the same content. The now c l a s s i c and widely r e p l i c a t e d v i s u a l perspect ive taking study of Lempers and F l a v e l l (1977) can be used to i l l u s t r a t e t h i s d i s t i n c t i o n . In t h i s study subjects were exposed to a p ic ture of a t u r t l e which appeared to be l y i n g on i t s back to one observer and r e s t i n g on i t s own four feet to another. In t h i s procedure, 3-year o ld c h i l d r e n demonstrated an understanding that when the other has absolute ly no v i s u a l access to the t u r t l e they see nothing at a l l , but s t i l l f a i l to understand that from t h e i r d i f f e r e n t viewing pos i t ions they and the other w i l l see the t u r t l e i n d i f f eren t or i en ta t ions . Somewhat o lder c h i l d r e n (4 years o ld ) , who are sa id to have achieved a l e v e l 2 understanding, were able not only to understand who could or could not see the t u r t l e at a l l , but also how they and others see i t . While l e v e l 2 perspect ive taking i s 83 decidedly more mature than i t s precursor, achieving l e v e l 1 i s no i n s i g n i f i c a n t feat for the young c h i l d . F l a v e l l (1978) maintains that for a c h i l d to achieve f u l l l e v e l 1 competence he or she must understand that i n order for another person to see an object four condit ions must hold: 1) at a minimum one of the other's eyes must be open and unencumbered; 2) the other 's eyes must be oriented i n the d i r e c t i o n of the object; 3) there must not be any phys ica l obstruct ions obscuring the object from the other 's v i s i o n ; and 4) what the c h i l d has v i s u a l access to i s independent from what the other sees. By 3 years of age most c h i l d r e n c l e a r l y evidence a f u l l understanding of a l l of these aspects of l e v e l 1 v i s u a l perspective taking ( F l a v e l l , 1977, i n press; F l a v e l l , F l a v e l l , Green & Wilcox, 1980; Lempers & F l a v e l l , 1977; Hughes and Donaldson, 1979). Some research suggests an even younger onset age on s i m p l i f i e d l e v e l 1 tasks. F l a v e l l , Shipstead and Croft (1978), for example, using a research design that tested Level 1 v i s u a l perspect ive taking i n terms of c h i l d r e n ' s a b i l i t y to hide an object from another, found that even 2 1/2 year olds knew how to deprive another of v i s u a l access to an object by p lac ing i t behind an opaque screen, thus demonstrating that they could d i s t i n g u i s h between what they and others saw. While proponents of the late-onset view (e .g. Hogrefe, 84 Wimmer & P e r n e r , 1986) do n o t a c c e p t l e v e l 1 p e r s p e c t i v e t a k i n g a s e v i d e n c e f o r t h e e x i s t e n c e o f a t h e o r y o f m i n d , t h e r e a r e r e a s o n s t o c o n s i d e r t h i s a c h i e v e m e n t a s i n d i r e c t s u p p o r t f o r an e a r l i e r o n s e t v i e w . P a r t i c u l a r l y r e l e v a n t i s t h e more r e c e n t w o r k t h a t c o n n e c t s l e v e l 1 p e r s p e c t i v e t a k i n g w i t h c h i l d r e n ' s e a r l y u n d e r s t a n d i n g t h a t p e r c e p t i o n i s a s o u r c e o f k n o w l e d g e ( e . g . P i l l o w , 1 9 8 7 ) . I n t h i s s t u d y , w h e r e d i f f e r e n t i a l a c c e s s t o a s t i m u l u s a r r a y was p r o v i d e d f o r s u b j e c t s and p u p p e t s , P i l l o w f o u n d t h a t e v e n 3 - y e a r - o l d s c o u l d c o r r e c t l y i n f e r t h e p r e s e n c e o r a b s e n c e o f k n o w l e d g e b a s e d on someone's p e r c e p t u a l e x p e r i e n c e . T h a t i s , t h e s e y o u n g c h i l d r e n c o u l d c o r r e c t l y a t t r i b u t e k n o w l e d g e o f t h e c o l o u r o f an o b j e c t t o w h o e v e r h a d s e e n t h e o b j e c t , b u t u n d e r s t o o d t h a t t h o s e who h a d n o t s e e n i t w o u l d be i g n o r a n t o f i t s c o l o u r . T h u s , c h i l d r e n seem t o u n d e r s t a n d t h a t a p e r s o n ' s k n o w l e d g e o r b e l i e f i s a r e s u l t o f p e r c e p t u a l a c c e s s t o i n f o r m a t i o n i n t h e r e a l w o r l d a n d , a s s u c h , b e l i e v e t h a t p e r c e p t u a l e x p e r i e n c e d e t e r m i n e s o n e ' s m e n t a l r e p r e s e n t a t i o n o f an e v e n t . I n g e n e r a l t h e n , i t i s c l e a r and l a r g e l y u n d i s p u t e d t h a t b y 2 1/2 t o 3 y e a r s o f age c h i l d r e n d e m o n s t r a t e t h e u s e o f a v a r i e t y o f s o c i a l c o g n i t i v e c a p a c i t i e s w h i c h i n d i c a t e a t l e a s t some u n d e r s t a n d i n g o f t h e m e n t a l w o r l d . V e r y e a r l y o n c h i l d r e n e n g a g e i n p r e t e n s e and somewhat l a t e r , b u t s t i l l p r i o r t o 3 y e a r s , j o i n i n c o o p e r a t i v e s o c i a l p r e t e n d p l a y , d e m o n s t r a t i n g a n u n d e r s t a n d i n g t h a t o t h e r s c a n r e p r e s e n t a c o n t r a r y - t o - f a c t s i t u a t i o n . Use a n d u n d e r s t a n d i n g o f m e n t a l s t a t e t e r m s a n d t h e 85 p a r a m e t e r s o f m e n t a l e n t i t i e s a l s o emerge a r o u n d t h i s same t i m e , a s d o e s l e v e l 1 v i s u a l p e r s p e c t i v e t a k i n g . I n a d d i t i o n t o p o s s e s s i n g t h e s e c a n d i d a t e e l e m e n t s o f a t h e o r y o f m i n d t h e r e i s some e v i d e n c e s u g g e s t i n g t h a t c h i l d r e n a s y o u n g a s 3 y e a r s a r e a l s o c a p a b l e o f c o m b i n i n g t h e s e e l e m e n t s t o p r e d i c t a n o t h e r ' s a c t i o n ( W e l l m a n & B a r t s c h , i n p r e s s ) . I n s p i t e o f t h i s i m p r e s s i v e l i s t o f a c c o m p l i s h m e n t s , h o w e v e r , t h e r e a r e many c o n t r i b u t o r s t o t h i s l i t e r a t u r e who a r e s t i l l u n w i l l i n g t o c r e d i t a l e g i t i m a t e t h e o r y o f m i n d t o c h i l d r e n u n d e r t h e age o f 4. I t i s t o t h i s l a t e - o n s e t v i e w t h a t a t t e n t i o n w i l l now b e t u r n e d . The L a t e - O n s e t V i e w I n c o n t r a s t t o t h o s e s u p p o r t e r s o f t h e e a r l y - o n s e t v i e w who c r e d i t c h i l d r e n a s y o u n g a s 2 1/2 w i t h h o l d i n g t o some b a s i c t h e o r y o f m i n d , t h o s e who s u p p o r t t h e n o t i o n o f a l a t e r o n s e t c l a i m i n s t e a d t h a t 4 o r 5 y e a r s o f age m a r k s t h e c r u c i a l t u r n i n g p o i n t i n t h i s a s p e c t o f y o u n g c h i l d r e n ' s e a r l y c o g n i t i v e d e v e l o p m e n t . T h i s d e b a t e b e t w e e n t h e c o m p e t i n g c l a i m s o f a d v o c a t e s o f t h e e a r l y - v e r s u s l a t e - o n s e t v i e w h a s a s i t s e s s e n t i a l p i v o t what one i s w i l l i n g t o t a k e a s e v i d e n c e f o r s u c h a t h e o r y . S u p p o r t e r s o f t h e l a t e - o n s e t v i e w , w h i l e a c k n o w l e d g i n g t h a t 3 - y e a r o l d s c a n i n f a c t do a l l t h a t o t h e r s c l a i m f o r them, a r g u e t h a t a l l s u c h e v i d e n c e i s s t i l l n o t e n o u g h t o w a r r a n t t h e l a b e l " t h e o r y o f m i n d " . P e r h a p s t h e m o s t c e n t r a l a n d c e r t a i n l y among t h e mos t p r o l i f i c c r i t i c s o f t h e e a r l y - o n s e t v i e w a r e Wimmer a n d P e r n e r ( 1 9 8 3 ) a nd t h e i r c o l l e a g u e s . T h e s e a u t h o r s s e e t h e a b i l i t y o f c h i l d r e n t o u n d e r s t a n d o p p o s i n g o r f a l s e b e l i e f s a s t h e r e a l l i t m u s t e s t f o r any t h e o r y o f m i n d . T h e r e a r e a number o f i m p o r t a n t a n d c o n v i n c i n g r e a s o n s why t h e a b i l i t y t o u n d e r s t a n d t h a t a n o t h e r may h o l d b e l i e f s w h i c h d i f f e r f r o m o n e ' s own s h o u l d s t a n d a s a c r u c i a l t e s t o f w h e t h e r one a d h e r e s t o a t h e o r y o f m i n d b u t t h e d e b a t e r e m a i n s o p e n a s t o when i n t h e l i v e s o f c h i l d r e n t h i s o c c u r s . I n t h e m a i n , s u p p o r t e r s o f t h e l a t e - o n s e t v i e w a g r e e t h a t i t i s i n s u f f i c i e n t t o show t h a t y o u n g c h i l d r e n know t h a t t h e y a n d o t h e r s h a v e i n t e n t i o n a l s t a t e s w h i c h d i f f e r f r o m t h e r e a l w o r l d , a n d h o l d o u t i n s t e a d f o r e v i d e n c e t h a t s u c h c h i l d r e n h a v e some w o r k i n g u n d e r s t a n d i n g o f t h o s e i n t e n t i o n a l s t a t e s t o w h i c h s u c h b e l i e f s a c t u a l l y c o r r e s p o n d . U n d e r s t a n d i n g b e l i e f s w h i c h a r e b a s e d on m u t u a l k n o w l e d g e c a n n o t b e shown t o r e q u i r e any a u t h e n t i c u n d e r s t a n d i n g o f b e l i e f s i n o t h e r s (Newman, 1986) a n d w h i l e t h e u n d e r s t a n d i n g o f f a l s e b e l i e f s may o c c u r s i m u l t a n e o u s l y , i t i s o n l y when d i f f e r e n t i a l a c c e s s t o i n f o r m a t i o n o c c u r s t h a t i t i s n e c e s s a r y f o r one t o know t h a t a n o t h e r may n o t s h a r e o n e ' s b e l i e f . Thus t e s t s o f c h i l d r e n ' s u n d e r s t a n d i n g o f b e l i e f s i n o t h e r s must go b e y o n d m u t u a l k n o w l e d g e t o d e m o n s t r a t e a c o h e s i v e t h e o r y o f m i n d . One d i m e n s i o n o f b e l i e f u n d e r s t a n d i n g t h a t h a s b e e n e x a m i n e d r e c e n t l y i s t h e q u e s t i o n o f w h e t h e r y o u n g c h i l d r e n c o n n e c t b e l i e f s w i t h t h e s o u r c e s f r o m w h i c h t h e y o r i g i n a t e . F o r e x a m p l e , G o p n i k a n d G r a f ( 1 9 8 9 ) f o u n d t h a t 3 - y e a r - o l d s d i d n o t a c c u r a t e l y i d e n t i f y t h e s o u r c e o f t h e i r own b e l i e f s . T h e s e r e s u l t s a p p e a r 87 i n c o n s i s t e n t w i t h t h o s e o b t a i n e d b y P i l l o w ( 1 9 8 7 ) i n w h i c h 3-y e a r - o l d s c o r r e c t l y i n f e r r e d t h e p r e s e n c e o r a b s e n c e o f k n o w l e d g e b a s e d o n a n o t h e r ' s p e r c e p t u a l e x p e r i e n c e . T h e s e two s t u d i e s , h o w e v e r , d i f f e r i n some o t h e r i m p o r t a n t a s p e c t s . I n P i l l o w ' s s t u d y s u b j e c t s w e re r e q u i r e d t o p r e d i c t what a n o t h e r w o u l d know on t h e b a s i s o f t h e a v a i l a b i l i t y o f p e r c e p t u a l i n f o r m a t i o n . The G o p n i k a n d G r a f s t u d y i n c o n t r a s t r e q u i r e d s u b j e c t s t o e x p l a i n a f t e r - t h e - f a c t w h e r e t h e i r own k n o w l e d g e o r b e l i e f s o r i g i n a t e d f r o m , a t a s k w h i c h r e q u i r e s a p o t e n t i a l l y more c o m p l e x a b i l i t y t o comment upon how one comes t o know a t h i n g r a t h e r t h a n w h a t one h a s t h e r i g h t t o know. The d i f f i c u l t y e x p e r i e n c e b y t h e 3 - y e a r -o l d s i n t h e G o p n i k a nd G r a f s t u d y d o e s n o t p r e c l u d e t h e p o s s i b i l i t y t h a t t h e s e y o u n g s u b j e c t s h a v e some u n d e r s t a n d i n g o f t h e n a t u r e o f b e l i e f s b u t may r e f l e c t t h e i r l a c k o f e x p e r t i s e i n a c c u r a t e l y c h o o s i n g among t h r e e p l a u s i b l e a l t e r n a t i v e s o u r c e s f o r a g i v e n b e l i e f . Much o f t h e c u r r e n t r e s e a r c h on c h i l d r e n ' s d e v e l o p i n g t h e o r i e s o f m i n d s t a n d s i n some d i r e c t l i n e a g e t o t h e now c l a s s i c w o r k o f t h e e t h o l o g i s t s P r e m a c k and W o o d r u f f ( 1 9 7 8 ) i n w h i c h t h e y a t t e m p t e d t o i l l u s t r a t e t h a t c h i m p a n z e e s c o u l d d e m o n s t r a t e an u n d e r s t a n d i n g o f t h e f a l s e b e l i e f s o f o t h e r s a n d c o n s e q u e n t l y some t h e o r y o f m i n d t h r o u g h t h e i r u s e o f v a r i o u s d e c e p t i v e s t r a t e g i e s . W h i l e a r g u i n g t h a t P r e m a c k and W o o d r u f f ' s w o r k f a l l s s h o r t o f i t s i n t e n d e d mark, D e n n e t t ( 1 9 7 8 ) l e a v e s o p e n t h e p o s s i b i l i t y t h a t p o s s e s s i o n o f some t h e o r y o f m i n d m i g h t b e d e m o n s t r a t e d b y u s i n g what he p r o p o s e s a s t h e " m i n i m a l 88 e x p e r i m e n t " f o r a t t r i b u t i n g d e c e p t i o n t o a n o r g a n i s m . I t i s D e n n e t t ' s m i n i m a l e x p e r i m e n t on w h i c h Wimmer a n d P e r n o r ' s ( 1 9 8 3 ) t e s t o f f a l s e - b e l i e f u n d e r s t a n d i n g i s b a s e d . B e f o r e t a k i n g up a d i s c u s s i o n o f t h i s p r o c e d u r e a n d t h e s e v e r a l d i f f e r e n t u s e s t o w h i c h i t h a s b e e n p u t , some a t t e n t i o n n e e d s t o b e p a i d t o t h e q u e s t i o n o f why a u t h o r s s u c h a s Wimmer an d P e r n e r r e m a i n u n i m p r e s s e d b y t h e r e s u l t s o f o t h e r p r o c e d u r e s . A c c o r d i n g t o P e r n e r , Leekam and Wimmer ( 1 9 8 7 ) t h e t e s t o f t h e p r e s e n c e o f a t h e o r y o f m i n d l i e s i n t h e c h i l d ' s a b i l i t y t o u n d e r s t a n d t h a t p e r s o n s may h o l d b e l i e f s w i t h c o n f l i c t i n g t r u t h v a l u e s . A t l e a s t t o d a t e , none o f t h e method s u s e d b y s u p p o r t e r s o f t h e e a r l y - o n s e t v i e w ( w i t h t h e p o s s i b l e e x c e p t i o n o f t h e r e c e n t C h a n d l e r , F r i t z & H a l a , i n p r e s s ) a p p e a r t o s a t i s f y t h i s t a s k . What c h i l d r e n a t t h i s e a r l i e r age c a n do, a c c o r d i n g t o P e r n e r e t a l , i s t o r e p r e s e n t a l t e r n a t i v e m o d e l s a n d a s s i g n a p p r o p r i a t e t r u t h v a l u e s t o t h e s e m o d e l s , w h a t t h e y c a n n o t y e t do, a c c o r d i n g t o t h e s e a u t h o r s , i s a s s i g n c o n f l i c t i n g t r u t h v a l u e s t o t h e m o d e l s . M e n t a l s t a t e t e r m s e v e n when u s e d a p p r o p r i a t e l y a n d when a d e q u a t e l y d i s t i n g u i s h e d f r o m t h e i r r e a l -w o r l d r e f e r e n t s p r o v i d e no s u c h e v i d e n c e . F o r e x a m p l e i f a 3-y e a r o l d c h i l d r e f e r s t o a dream t h e r e i s no q u e s t i o n t h a t a n o t h e r m i g h t b e l i e v e t h a t dream t o b e r e a l i t y . S i m i l a r l y , s o c i a l p r e t e n d p l a y w h i l e c l e a r l y i n v o l v i n g c l a i m s a t v a r i a n c e w i t h t h e t r u t h , n e e d n o t i n v o l v e an a w a r e n e s s o f c o n f l i c t i n g t r u t h v a l u e s f o r t h e r e a s o n t h a t no one i n s u c h i n t e r a c t i o n s assumes t h e p r e t e n s e t o be t r u e . What i s r e q u i r e d i n t h e c a s e o f c o n f l i c t i n g t r u t h v a l u e s a c c o r d i n g t o P e r n e r e t a l , i s t h a t n o t o n l y d o e s t h e c h i l d u n d e r s t a n d t h a t a p r o p o s i t i o n o r m o d e l i s a t v a r i a n c e w i t h what he o r s h e t a k e s t o be t r u e b u t a l s o t h a t a n o t h e r p e r s o n s i m u l t a n e o u s l y deems t h i s f a l s e m o d e l t o b e t r u e . The a b i l i t y t o a s s i g n s u c h c o n f l i c t i n g t r u t h v a l u e s , w h i c h i s s a i d t o o c c u r a r o u n d 4 y e a r s o f a g e , i s assumed b y P e r n e r a n d h i s c o l l e a g u e s t o be r e s p o n s i b l e f o r s u c c e s s o n a number o f t a s k s i n c l u d i n g t h e u n e x p e c t e d c h a n g e p r o c e d u r e , a p p e a r a n c e -r e a l i t y m e a s u r e s , a n d l e v e l 2 p e r s p e c t i v e t a k i n g . T h i s f o l l o w s , a c c o r d i n g t o t h e s e a u t h o r s , b e c a u s e F l a v e l l ' s l e v e l 2 o f v i s u a l p e r s p e c t i v e t a k i n g i n v o l v e s n o t o n l y t h e a b i l i t y t o u n d e r s t a n d w h e t h e r a n o t h e r p e r s o n w i t h d i f f e r e n t i a l v i s u a l a c c e s s c o u l d s e e a n o b j e c t b u t a l s o how t h e y saw t h a t o b j e c t . T h a t i s , c h i l d r e n m ust h o l d i n m i n d what t h e y t h e m s e l v e s s e e b u t u n d e r s t a n d t h a t t h e o t h e r may p e r c e i v e t h e o b j e c t i n some way w h i c h c o n f l i c t s w i t h t h e i r own v i e w . S i m i l a r l y , t h e a p p e a r a n c e - r e a l i t y d i s t i n c t i o n ( e . g . F l a v e l l , i n p r e s s ; F l a v e l l , F l a v e l l & G r e e n , 1983, 1987; F l a v e l l , G r e e n & F l a v e l l , 1986; T a y l o r & F l a v e l l , 1984) a l s o r e q u i r e s t h a t t h e c h i l d h o l d two d i f f e r e n t m o d e l s o f r e a l i t y i n m i n d a t o n c e , t h e m o d e l o f t h e o b j e c t a s i t a p p e a r s and t h e m o d e l o f t h e o b j e c t a s i t t r u l y i s . An o b j e c t may, f o r e x a m p l e , l o o k l i k e a r o c k b u t u p o n c l o s e r e x a m i n a t i o n and h a n d l i n g may b e shown t o b e r e a l l y a s p o n g e . A t 3 y e a r s o f age ( T a y l o r & F l a v e l l , 1984) c h i l d r e n c a n s e p a r a t e t h e r e a l f r o m t h e a p p a r e n t b u t c a n n o t u n d e r s t a n d t h a t t h e same o b j e c t c o u l d be r e p r e s e n t e d e i t h e r a s a r o c k o r a s p o n g e 90 d e p e n d i n g on t h e o b s e r v e r ' s p o i n t o f v i e w . I n a s i m i l a r s t u d y u s i n g v a r i a t i o n s o f s t a n d a r d a p p e a r a n c e - r e a l i t y a n d f a l s e - b e l i e f t a s k s , G o p n i k a n d A s t i n g t o n ( 1 9 8 8 ) f o u n d t h a t o v e r h a l f o f t h e i r 3 - y e a r o l d s u b j e c t s w e r e u n a b l e t o s u c c e e d a n d t e n d e d t o t r e a t t h e i r c u r r e n t r e p r e s e n t a t i o n o f a t h i n g a s t h e o n l y r e p r e s e n t a t i o n p o s s i b l e i n b o t h t y p e s o f t a s k s . T h e s e a u t h o r s f u r t h e r f o u n d t h a t t h e a p p e a r a n c e - r e a l i t y t a s k s w e r e more d i f f i c u l t f o r t h e c h i l d r e n t h a n t h e f a l s e - b e l i e f t a s k s l e n d i n g s u p p o r t t o F l a v e l l ' s a s s e r t i o n ( F l a v e l l , F l a v e l l , & G r e e n , 1983) t h a t u n d e r s t a n d i n g f a l s e b e l i e f i s n e c e s s a r y f o r u n d e r s t a n d i n g t h e a p p e a r a n c e - r e a l i t y d i s t i n c t i o n b e c a u s e c h i l d r e n must g r a s p t h e n o t i o n t h a t a n o t h e r c a n b e l i e v e s o m e t h i n g w h i c h t h e y t h e m s e l v e s know t o be f a l s e . I n v i e w o f t h e f a c t t h a t t h e u n d e r s t a n d i n g o f f a l s e b e l i e f i s s a i d t o f o r m a b a s i s f o r many o t h e r r e l a t e d c o g n i t i v e a b i l i t i e s i t seems p a r t i c u l a r l y i m p o r t a n t t o h a v e a m e a s u r e m e n t p r o c e d u r e t h a t a d e q u a t e l y g a u g e s i t s e m e r g e n c e i n y o u n g c h i l d r e n . The f o l l o w i n g s e c t i o n d e s c r i b e s i n d e t a i l t h i s s t a n d a r d W i m m e r - P e r n e r u n e x p e c t e d c h a n g e m e a s u r e . The U n e x p e c t e d Change P a r a d i g m The b a s i c f e a t u r e o f Wimmer and P e r n e r ' s o r i g i n a l u n e x p e c t e d c h a n g e t a s k a n d i t s many v a r i a t i o n s i s t h a t i t c r e a t e s a c o n t e x t i n w h i c h t h e s u b j e c t a n d a n o t h e r h a v e d i f f e r e n t i a l a c c e s s t o i n f o r m a t i o n . S u b j e c t s a r e t o l d a s t o r y i n w h i c h t h e y a r e made p r i v y t o an u n e x p e c t e d t u r n o f e v e n t s a b o u t w h i c h t h e s t o r y p r o t a g o n i s t ( a d o l l f i g u r e ) h a s no k n o w l e d g e . I n one s u c h v a r i a t i o n u p o n t h i s p r o c e d u r e (Wimmer and P e r n e r , 1983) t h e c h i l d 91 watches a scene enacted by a mother and son d o l l f i g u r e i n a playhouse c o n t a i n i n g two cupboards. The mother and the boy, Maxi, have j u s t r e t u r n e d from shopping and, among other items, some c h o c o l a t e has been purchased. The c h o c o l a t e i s p l a c e d i n cupboard A i n Maxi's presence. Then Maxi l e a v e s the house t o p l a y . During Maxi's absence the mother removes the c h o c o l a t e from cupboard A, g r a t e s a l i t t l e t o make a cake, and p l a c e s the ch o c o l a t e , not back i n cupboard A, but i n cupboard B. In more rece n t " e x p l i c i t " v e r s i o n s of t h i s t a s k the s u b j e c t i s reminded t h a t Maxi does not see t h i s unexpected t r a n s f e r . The s u b j e c t i s then t o l d t h a t upon h i s r e t u r n , Maxi w i l l want some c h o c o l a t e . The t e s t q u e s t i o n s asked of the s u b j e c t a t t h i s p o i n t are " W i l l Maxi know where the c h o c o l a t e i s " and more i m p o r t a n t l y "Where w i l l Maxi look f o r the c h o c o l a t e " . I f s u b j e c t s answer c o r r e c t l y w i t h the o r i g i n a l l o c a t i o n of the c h o c o l a t e ( i . e . cupboard A) then they are c r e d i t e d w i t h understanding f a l s e b e l i e f s and assumed t o possess some o p e r a t i v e theory of mind. I f , by c o n t r a s t , they respond w i t h the a c t u a l new l o c a t i o n of the ch o c o l a t e ( i . e . Cupboard B), they are s a i d t o l a c k an understanding of the c o u n t e r f a c t u a l nature of f a l s e b e l i e f s and other forms of evidence, of the s o r t promoted by advocates of the e a r l y - o n s e t view are d i s c o u n t e d as having no s t a t u s . Wimmer and Perner's o r i g i n a l unexpected change paradigm proved t o be a powerful impetus t o other r e s e a r c h i n t o c h i l d r e n ' s thoughts about the mental l i v e s of other persons, and w h i l e l o c a t i n g the t h r e s h o l d f o r such an understanding r e l a t i v e l y l a t e , 92 a s c o m p a r e d t o t h e c l a i m s o f t h o s e d i s c u s s e d i n t h e p r e c e d i n g s e c t i o n , i t d o e s i n f a c t p l a c e t h e em e r g e n c e o f t h i s a b i l i t y a t a y o u n g e r age t h a n h a s b e e n s u g g e s t e d b y many s t u d i e s b a s e d u p o n s t i l l e a r l i e r m e a s u r e s o f c o n c e p t u a l p e r s p e c t i v e t a k i n g ( e . g . S e l m a n , 1980; S h u l t z & C l o g h e s y , 1 9 8 1 ) . I n p a r t i c u l a r , t h e r e a r e two m a j o r a d v a n t a g e s o f t h e W i m m e r - P e r n e r p a r a d i g m o v e r p r e v i o u s r e s e a r c h i n t h i s a r e a . The f i r s t c o n c e r n s t h e f a c t t h a t t h e s e i n v e s t i g a t o r s s u c c e s s f u l l y d e s i g n e d an a s s e s s m e n t p r o c e d u r e w h i c h i s n o t , i n t h e m a i n , d e p e n d e n t u pon o r c o n f o u n d e d w i t h y o u n g c h i l d r e n ' s a b i l i t i e s t o v e r b a l l y a r t i c u l a t e w h a t t h e y a r e t h i n k i n g . Much o f t h e p r e v i o u s r e s e a r c h i n t h i s a r e a c l e a r l y was o v e r r e l i a n t u p o n c h i l d r e n ' s e x p l i c i t v e r b a l r e p o r t s . Wimmer and P e r n e r a c h i e v e t h i s p r o c e d u r a l a d v a n c e b y h a v i n g t h e i r s u b j e c t s s i m p l y p o i n t t o t h e c u p b o a r d i n w h i c h t h e y t h i n k M a x i w i l l l o o k f o r t h e c h o c o l a t e . T h i s p a r a d i g m a l s o a v o i d s t h e r e c u r s i v e , o f t e n n o n i n t e r p r e t a b l e n a t u r e o f many e a r l i e r r o l e - t a k i n g a s s e s s m e n t p r o c e d u r e s b a s e d on c o m p e t i t i v e game s t r a t e g i e s ( S e l m a n , 1980; S h u l t z & C l o g h e s y , 1 9 8 1 ) , i n w h i c h b o t h l o w e r l e v e l a n d h i g h e r l e v e l s t r a t e g i e s w e r e m a n i f e s t i n t h e v e r y same a c t i o n . S i n c e 1983 t h e o r i g i n a l Wimmer and P e r n e r u n e x p e c t e d c h a n g e a s s e s s m e n t p a r a d i g m h a s b e e n u s e d w i t h numerous v a r i a t i o n s b y t h e s e a u t h o r s a n d t h e i r c o l l e a g u e s , i n o r d e r t o b o t h r e p l i c a t e t h e s e e a r l i e r f i n d i n g s a n d i n a n e f f o r t t o d e t e r m i n e w h a t i t i s t h a t makes t h e u n d e r s t a n d i n g o f f a l s e b e l i e f s o a p p a r e n t l y , d i f f i c u l t f o r c h i l d r e n y o u n g e r t h a n 4 y e a r s . What f o l l o w s i s a 93 s y n o p s i s o f t h e f i n d i n g s f r o m t h e s e s e v e r a l s t u d i e s . The o r i g i n a l s e t o f s t u d i e s w h i c h i n t r o d u c e d t h i s s t a n d a r d u n e x p e c t e d c h a n g e p a r a d i g m (Wimmer & P e r n e r , 1983) i n v o l v e d an a t t e m p t t o l o c a t e c h i l d r e n ' s f i r s t u n d e r s t a n d i n g o f t h e b e l i e f s o f o t h e r s a t a y o u n g e r age t h a n h a d b e e n p r o p o s e d p r e v i o u s l y . C o n s e q u e n t l y , i n r e s p o n s e t o e a r l i e r f i n d i n g s t h a t p l a c e d s u c h u n d e r s t a n d i n g i n t h e m i d d l e s c h o o l y e a r s , t h e a g e s e x a m i n e d i n t h e f i r s t e x p e r i m e n t r a n g e d f r o m 4 y e a r s t o 9 y e a r s . The r e s u l t s o f t h i s s t u d y c l e a r l y showed t h a t w h i l e t h e 6- t o 9- y e a r o l d s c o r r e c t l y a n s w e r e d t h e t e s t q u e s t i o n s , t h e m a j o r i t y o f 4- t o 5-y e a r o l d s f a i l e d t o do s o . I n a s e c o n d e x p e r i m e n t i n v o l v i n g 3-and 4 - y e a r o l d s , t h e a u t h o r s a t t e m p t e d t o make t h e t a s k e a s i e r by i n c l u d i n g " s t o p - a n d - t h i n k " i n s t r u c t i o n s t o g u a r d a g a i n s t t h e i m p e t u o u s r e s p o n s e s g i v e n b y v e r y y o u n g c h i l d r e n . A " d i s a p p e a r " c o n d i t i o n was a l s o i n c l u d e d i n w h i c h t h e c h o c o l a t e was n o t s i m p l y d i s p l a c e d w h i l e M a x i was o u t o f t h e room b u t was r e m o v e d f r o m t h e s c e n e e n t i r e l y . Wimmer an d P e r n e r f o u n d t h a t o n l y t h e d i s a p p e a r c o n d i t i o n f a c i l i t a t e d i m p r o v e m e n t i n t h e p e r f o r m a n c e on u n e x p e c t e d c h a n g e t a s k s a n d t h e n o n l y f o r t h e 4 y e a r o l d s , w i t h t h e m a j o r i t y ( 7 6 % ) p a s s i n g t h e d i s a p p e a r c o n d i t i o n b u t o n l y a m i n o r i t y ( 4 1 % ) p a s s i n g t h e s t a n d a r d u n e x p e c t e d c h a n g e p a r a d i g m . The 3 - y e a r o l d s p e r f o r m e d p o o r l y and b e l o w c h a n c e on a l l c o n d i t i o n s , w i t h t h e i r b e s t p e r f o r m a n c e ( 3 0 % c o r r e c t ) o c c u r r i n g on t h e d i s a p p e a r c o n d i t i o n . I n a number o f r e l a t e d e x p e r i m e n t s Wimmer, P e r n e r a n d t h e i r c o l l e a g u e s a l s o h a v e u t i l i z e d c o r r e c t r e s p o n s e s on t h e i r 94 u n e x p e c t e d c h a n g e t a s k a s a c r i t e r i a l m e a s u r e w i t h w h i c h t o e x c l u d e s u b j e c t s s a i d t o b e l a c k i n g any t h e o r y o f m i n d f r o m f u r t h e r p a r t i c i p a t i o n i n s t u d i e s o f o t h e r r e l a t e d c o g n i t i v e a b i l i t i e s s u c h a s t h e u n d e r s t a n d i n g o f l y i n g (Wimmer, G r u b e r & P e r n e r , 1984; 1985) o r t h e u n d e r s t a n d i n g o f t h e m i n d a s a n a c t i v e p r o c e s s o r o f i n f o r m a t i o n ( Leekam & P e r n e r , 1 9 8 7 ) . I n t h e s e s c r e e n i n g p r o c e d u r e s t h e y o u n g e s t s u b j e c t s i n c l u d e d w e r e 4 y e a r s o f a ge, a l o w e r age l i m i t a r r i v e d a t on t h e b a s i s o f t h e e a r l i e r s t u d y w h i c h s u g g e s t e d c h i l d r e n u n d e r 4 - y e a r s o l d c o u l d n o t c o m p r e h e n d f a l s e b e l i e f . I n t h e s t u d i e s on l y i n g t h e p e r f o r m a n c e o f 4 1 / 2 - y e a r o l d s o n a s t a n d a r d u n e x p e c t e d c h a n g e t e s t , w h i l e s u b s t a n t i a l l y b e t t e r t h a n t h a t f o u n d i n t h e o r i g i n a l Wimmer a n d P e r n e r a r t i c l e , s t i l l r e m a i n s f a r f r o m p e r f e c t , r a n g i n g f r o m 5 7 % i n t h e e a r l i e r s t u d y t o 6 8 % i n t h e more r e c e n t e x p e r i m e n t (Wimmer, G r u b e r a n d P e r n e r , 1984, 1 9 8 5 ) . The more r e c e n t Leekam and P e r n e r s t u d y ( 1 9 8 7 ) f o u n d a d r a m a t i c i n c r e a s e i n t h e number o f 4 1 / 2 - y e a r o l d s p a s s i n g t h e u n e x p e c t e d c h a n g e m e a s u r e o f f a l s e - b e l i e f u n d e r s t a n d i n g ( 9 1 % ) b u t s t i l l o n l y 6 6 % o f 4 - y e a r o l d s . No 3 - y e a r o l d s w e r e i n c l u d e d i n a n y o f t h e s e s c r e e n i n g s t u d i e s . A d d i t i o n a l s t u d i e s i n w h i c h u n d e r s t a n d i n g o f f a l s e b e l i e f s r e s u l t i n g f r o m a n e n e x p e c t e d c h a n g e was among t h e c e n t r a l t o p i c s a d d r e s s e d h a v e shown f a i r t o good p e r f o r m a n c e f o r 4 - y e a r o l d s , b u t p e r f o r m a n c e b y 3 - y e a r o l d s r e m a i n s p o o r a c r o s s a l l t h e s t u d i e s . H o g r e f e , Wimmer and P e r n e r ( 1 9 8 6 ) , f o r e x a m p l e , f o u n d t h a t 5 6 % o f t h e i r 4 - y e a r o l d s p a s s e d t h e f a l s e - b e l i e f q u e s t i o n s w h i l e o n l y 1 7 % o f t h e 3 - y e a r o l d s d i d s o . B a s e d on A u s t r i a n a n d E n g l i s h s a m p l e s P e r n e r a n d Wimmer ( 1 9 8 7 ) f o u n d t h a t 6 5 % o f 4 - y e a r o l d s p a s s e d t h e t e s t q u e s t i o n s c o m p a r e d w i t h o n l y 3 8 % o f t h e 3-y e a r o l d s . W e l l m a n a nd B a r t s c h ( i n p r e s s ) , u s i n g s i m p l i f i e d f a l s e - b e l i e f m e a s u r e s i n w h i c h s u b j e c t s w e r e n o t r e q u i r e d t o i n f e r t h e p r o t a g o n i s t s b e l i e f s , a l s o f o u n d c o n t i n u e d p o o r p e r f o r m a n c e f o r 3 - y e a r o l d s a n d c h a n c e p e r f o r m a n c e f o r 4 - y e a r o l d s , w i t h o n l y t h e 4 1 / 2 - y e a r o l d s r e g u l a r l y p e r f o r m i n g s i g n i f i c a n t l y a b o v e c h a n c e . S i m i l a r l y , i n a v a r i a t i o n o f t h e s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e w h i c h r e q u i r e d s u b j e c t s t o comment upon t h e i r own p r e v i o u s l y - h e l d f a l s e b e l i e f s r a t h e r t h a n t h e f a l s e b e l i e f s h e l d b y a n o t h e r , G o p n i k a nd A s t i n g t o n ( 1 9 8 8 ) f o u n d t h e m a j o r i t y o f t h e i r 3 - y e a r o l d s f a i l e d t o a c c u r a t e l y s t a t e w h a t t h e i r o r i g i n a l b e l i e f h a d b e e n s u b s e q u e n t t o a d e m o n s t r a t i o n t h a t t h i s b e l i e f was f a l s e . P o s s i b l y t h e most g e n e r o u s p i c t u r e t h a t c a n b e p a i n t e d o f y o u n g c h i l d r e n ' s u n d e r s t a n d i n g o f f a l s e - b e l i e f b a s e d o n t h e Wi m m e r - P e r n e r p a r a d i g m a p p e a r s i n an a r t i c l e i n w h i c h P e r n e r , Leekam a n d Wimmer ( 1 9 8 7 ) r e m o v e d some o f t h e p o t e n t i a l s t u m b l i n g b l o c k s t o c o r r e c t p e r f o r m a n c e . I n t h i s s t u d y , i n a d d i t i o n t o " s t o p - a n d - t h i n k " i n s t r u c t i o n s , p r o b e s w e r e u s e d t h r o u g h o u t t o r e m i n d c h i l d r e n o f who h a d a c c e s s t o what i n f o r m a t i o n . W i t h t h e s e m e t h o d o l o g i c a l r e f i n e m e n t s a s u b s t a n t i a l i m p r o v e m e n t was f o u n d f o r t h e o l d e r age g r o u p s w i t h 4 t o 4 1 / 2 - y e a r o l d s p e r f o r m i n g a l m o s t a t c e i l i n g ( 9 6 % ) a n d 3 1/2 t o 4 - y e a r o l d s now 7 5 % c o r r e c t . I n s p i t e o f t h e s e i m p r o v e m e n t s , t h e y o u n g e s t g r o u p 96 o f 3 t o 3 1 / 2 - y e a r o l d s c o n t i n u e d t o p e r f o r m p o o r l y ( 2 4 % c o r r e c t ) . B a s e d on t h e s e r e c e n t r e s u l t s t h e a u t h o r s h a v e m o d i f i e d t h e i r e a r l i e r p o s i t i o n i n w h i c h t h e y h e l d t h a t o n l y c h i l d r e n who a r e 4 - y e a r s o f age o r o l d e r u n d e r s t a n d f a l s e b e l i e f s , c u r r e n t l y a l l o w i n g t h a t 3 1/2 t o 4 y e a r s may r e p r e s e n t a t r a n s i t i o n p e r i o d d u r i n g w h i c h u n d e r s t a n d i n g a b o u t b e l i e f s b e g i n s t o emerge. D e s p i t e t h e n what a p p e a r s t o be a g r e a t d e a l o f b a c k and f i l l r e g a r d i n g e x a c t a g e s , t h e s e a u t h o r s c o n f i d e n t l y m a i n t a i n t h a t c h i l d r e n 3 y e a r s o f age o r y o u n g e r d e f i n i t e l y do n o t u n d e r s t a n d t h e n a t u r e o f f a l s e b e l i e f s i n o t h e r s . I n f a c t , i n t h e i r 1987 a r t i c l e P e r n e r , Leekam a n d Wimmer go s o f a r a s t o s u g g e s t t h a t t h e r e may be some a s y e t u n s p e c i f i e d c o g n i t i v e d e f i c i t t h a t w h o l l y b l o c k s c h i l d r e n y o u n g e r t h a t 3 1/2 f r o m h o l d i n g t o any s o r t o f b e l i e f a b o u t b e l i e f s . A l l t h i n g s c o n s i d e r e d , t h e a v a i l a b l e e v i d e n c e on c h i l d r e n ' s e a r l y t h e o r i e s o f m i n d c o u l d h a r d l y b e more c o n t r a d i c t o r y . On t h e one s i d e t h e r e a r e t h o s e a d v o c a t e s o f t h e e a r l y o n s e t v i e w who s e e e v i d e n c e o f t h e s e a b i l i t i e s i n a b r o a d v a r i e t y o f p e r f o r m a n c e s common t o 2- a n d 3 - y e a r o l d s . On t h e o t h e r a r e t h o s e p r o p o n e n t s o f v a r i o u s f a l s e - b e l i e f m e a s u r e s who h a v e a n i m p r e s s i v e b o d y o f e v i d e n c e t h a t s p e a k s a g a i n s t t h a t p o s s i b i l i t y . Two p o s s i b l e s o l u t i o n s t o t h i s d i l e m m a s u g g e s t t h e m s e l v e s . E i t h e r c h i l d r e n y o u n g e r t h a n 3 1/2 o r 4 r e a l l y a r e u n a b l e t o u n d e r s t a n d t h e n a t u r e o f b e l i e f s , s p e c i f i c a l l y f a l s e b e l i e f s i n o t h e r s , a s P e r n e r e t a l . m a i n t a i n , o r t h e r e e x i s t some m e t h o d o l o g i c a l i n s u f f i c i e n c i e s o r c o n f o u n d s t h a t p r e v e n t s t a n d a r d 97 u n e x p e c t e d c h a n g e m e a s u r e s o f f a l s e - b e l i e f f r o m p r o p e r l y b r i n g i n g s u c h a b i l i t i e s t o l i g h t ( C h a n d l e r , F r i t z & H a l a , i n p r e s s ) . P r o p o n e n t s o f t h e d e l a y e d o n s e t v i e w ( H o g r e f e , Wimmer & P e r n e r , 1 9 8 6 ; P e r n e r , i n p r e s s ; P e r n e r & Wimmer, 1987; Wimmer & P e r n e r , 1983) c l a i m t h a t what s e p a r a t e s c h i l d r e n who c o r r e c t l y r e s p o n d t o s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e s o f f a l s e b e l i e f a t t r i b u t i o n f r o m t h o s e who do n o t i s t h e a b i l i t y t o a s s i g n i n c o m p a t i b l e t r u t h v a l u e s t o t h e same p r o p o s i t i o n . A c c o r d i n g t o t h e s e a u t h o r s , 3 - y e a r o l d s q u i t e s i m p l y c a n n o t u n d e r s t a n d t h a t t h o s e who h o l d t o o b j e c t i v e l y f a l s e b e l i e f s a c t u a l l y m i s t a k e n l y j u d g e s u c h f a l s e b e l i e f s t o be t r u e . I t i s t h i s u n d e r s t a n d i n g o f t h e p o s s i b i l i t y t h a t a n o t h e r m i g h t deem t r u e a p r o p o s i t i o n w h i c h t h e y t h e m s e l v e s know t o be f a l s e t h a t i s c l a i m e d t o s e p a r a t e t h o s e s u b j e c t s w i t h a p r o p e r u n d e r s t a n d i n g o f f a l s e b e l i e f , f r o m t h o s e w i t h o u t ( H o g r e f e e t a l . 1 9 8 6 ) . B o t h t h e d a t a a n d t h e a r g u m e n t s i n s u p p o r t o f t h i s t o u g h - m i n d e d v i e w a r e v e r y p e r s u a s i v e a n d e v e n some who o t h e r w i s e e n d o r s e t h e e a r l y - o n s e t v i e w c o n c e d e t h a t c h i l d r e n may be d o i n g s o m e t h i n g f u n d a m e n t a l l y d i f f e r e n t when t h e y p a s s t h e u n e x p e c t e d c h a n g e t a s k s . T h a t i s , w h i l e i n s i s t i n g t h a t e v e n 2 - y e a r o l d s who c a n e n g a g e i n p r e t e n d p l a y must i n some s e n s e r e p r e s e n t c e r t a i n s i t u a t i o n s a s c o u n t e r f a c t u a l , L e s l i e ( i n p r e s s ) , f o r e x a m p l e , s u g g e s t s t h a t p r e t e n s e i n v o l v e s a d e c o u p l e d e x p r e s s i o n w h i c h i s n e i t h e r t r u e n o r f a l s e , i n t h a t a l l p a r t i c i p a n t s i n t h e p r e t e n s e a r e meant t o u n d e r s t a n d t h a t t h e p r e t e n s e i s n o t r e a l . E v e n i f s u c h d e c o u p l i n g r e p r e s e n t s an a c c o m p l i s h m e n t t h a t i s l o g i c a l l y 98 d i f f e r e n t f r o m u n d e r s t a n d i n g c o u n t e r f a c t u a l s i n o t h e r s i t d o e s n o t , h o w e v e r , n e c e s s a r i l y f o l l o w t h a t t h e s e c o g n i t i v e a c c o m p l i s h m e n t s a r e t o t a l l y d i v o r c e d f r o m one a n o t h e r , w i t h u n d e r s t a n d i n g f a l s e b e l i e f s a r r i v i n g on t h e s c e n e a t a much l a t e r d a t e . I t i s e n t i r e l y p o s s i b l e t h a t a c o n c e p t o f c o u n t e r f a c t u a l s i s a r r i v e d a t s i m u l t a n e o u s l y o r a t l e a s t v e r y c l o s e l y on t h e h e e l s o f t h e a b i l i t y t o e n g a g e i n p r e t e n d p l a y . Q u i t e a p a r t f r o m any c l a i m s f o r o r a g a i n s t t h i s n o t i o n o f i n c o m p a t i b l e t r u t h v a l u e s , h o w e v e r , t h e r e e x i s t s a number o f o t h e r more mundane r e a s o n s a s t o why y o u n g c h i l d r e n m i g h t e x p e r i e n c e d i f f i c u l t y i n r e s p o n d i n g c o r r e c t l y t o t h e s t a n d a r d W i m m e r - P e r n e r p r o c e d u r e . One o f t h o s e c o m p l e x i t i e s i s t h e r o l e t h a t i n f e r e n c e p l a y s i n u n d e r s t a n d i n g t h e u n e x p e c t e d c h a n g e t a s k . L e s l i e ( 1 9 8 8 ) s u g g e s t s t h a t c h i l d r e n a s y o u n g a s 3 y e a r s c a n r e p r e s e n t a f a l s e b e l i e f a n d t h a t i t i s f a l s e b u t a r e u n a b l e t o i n f e r f r o m a s i t u a t i o n t o a f a l s e b e l i e f . I n t h e s t a n d a r d u n e x p e c t e d c h a n g e p a r a d i g m (Wimmer & P e r n e r , 1983; P e r n e r , Leekam & Wimmer, 1987) s u b j e c t s m u s t i n f e r w h e r e M a x i h a s a r i g h t t o b e l i e v e t h e c h o c o l a t e i s , b a s e d on t h e i n f o r m a t i o n a v a i l a b l e t o h i m . A number o f i n v e s t i g a t o r s ( L e s l i e , i n p r e s s ; P e r n e r & Wimmer, 1987; a n d W e l l m a n & B a r t s c h , i n p r e s s ) h a v e s u g g e s t e d t h a t some o f t h e d i f f i c u l t y 3 - y e a r o l d s h a v e w i t h t h e s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e o f f a l s e b e l i e f may be i n m a n a g i n g t h i s i n c i d e n t a l i n f e r e n c e p r o b l e m . I n o r d e r t o t e s t t h i s p o s s i b i l i t y P e r n e r a n d Wimmer ( 1 9 8 7 ) a d d e d a " m i s i n f o r m a t i o n s t o r y " w h i c h m i n i m i z e d i n f e r e n t i a l c o m p l e x i t y f o r f a l s e - b e l i e f a t t r i b u t i o n . T h e s e a u t h o r s f o u n d t h a t w h i l e 3 - y e a r o l d s p e r f o r m e d somewhat b e t t e r t h a n i n p r e v i o u s s t u d i e s t h e i r c o r r e c t r e s p o n s e s w e r e s t i l l w e l l b e l o w c h a n c e ( 3 7 % ) . S i m i l a r l y , W e l l m a n a n d B a r t s c h ( i n p r e s s ) h a v e a l s o i n t r o d u c e d a v a r i a t i o n u p o n t h e s t a n d a r d f a l s e - b e l i e f p a r a d i g m t h a t i s i n t e n d e d t o e l i m i n a t e t h i s i n f e r e n t i a l s t e p b y p r o v i d i n g s u b j e c t s w i t h an e x p l i c i t s t a t e m e n t o f t h e p r o t a g o n i s t s b e l i e f s . E v e n i n t h i s i n f e r e n t i a l l y l e s s c o m p l e x f o r m , h o w e v e r , 3 - y e a r o l d s c o n t i n u e d t o h a v e d i f f i c u l t y c o r r e c t l y a n s w e r i n g t h e f a l s e - b e l i e f t e s t q u e s t i o n s . A l t h o u g h t h e s e f i n d i n g s a r e n o t d e f i n i t i v e , t h e y do s u g g e s t t h e h e a v y i n f e r e n t i a l demands o f t h e o r i g i n a l W i m m e r - P e r n e r m e a s u r e may n o t b e t h e s o u r c e o f any s p e c i a l d i f f i c u l t i e s o c c a s i o n e d b y t h i s p r o c e d u r e . A l t e r n a t i v e l y , C h a n d l e r , F r i t z a nd H a l a ( i n p r e s s ) h a v e s u g g e s t e d t h a t t h e r e w e r e e n o u g h u n n e c e s s a r y p r o c e d u r a l c o m p l e x i t i e s i n h e r e n t i n t h e W i m m e r - P e r n e r p r o c e d u r e t o o a s t d o u b t u p o n i t s s t a n d i n g a s a n o p t i m a l a s s e s s m e n t o f c h i l d r e n ' s u n d e r s t a n d i n g o f c o u n t e r f a c t u a l b e l i e f s . The f i r s t s u c h c a n d i d a t e p o s s i b i l i t y i s t h e h i g h d e g r e e o f v e r b a l c o m p e t e n c e demanded b y t h e u n e x p e c t e d c h a n g e p r o c e d u r e . Wimmer and P e r n e r ( 1 9 8 3 ) p o i n t t o t h i s v e r y same l i m i t a t i o n i n t h e w o r k o f o t h e r s and i t was i n a n e f f o r t t o m i n i m i z e t h i s p r o b l e m t h a t t h e y a t t e m p t e d t o remove v e r b a l f l u e n c y a s a p o s s i b l e c o n f o u n d b y h a v i n g s u b j e c t s e x p r e s s t h e i r b e l i e f a b o u t t h e p r o t a g o n i s t ' s b e l i e f b y s i m p l y p o i n t i n g t o t h e l o c a t i o n w h e r e t h e y t h o u g h t M a x i w o u l d l o o k . D e s p i t e t h i s o t h e r w i s e u s e f u l a r r a n g e m e n t , t h e 100 r a t h e r c o m p l e x n a r r a t i v e o f t h e s t o r y p r o b l e m s u s e d n e v e r t h e l e s s c o n t i n u e t o make h e a v y demands upon c h i l d r e n ' s s t o r y c o m p r e h e n s i o n a b i l i t i e s . C o n s e q u e n t l y , e v e n when e x p l i c i t p r o b e s a r e u s e d t h r o u g h o u t t h e n a r r a t i v e , i t c a n n o t b e e s t a b l i s h e d w i t h c e r t a i n t y t h a t y o u n g s u b j e c t s c a n s u c c e s s f u l l y c o m b i n e a l l t h e s t o r y e l e m e n t s i n t o one c o h e s i v e u n i t . O b v i o u s l y , a n y f a i l i n g s on t h e p a r t o f s u b j e c t s i n t h i s q u a r t e r w o u l d d r a m a t i c a l l y r e d u c e t h e i r p e r f o r m a n c e on t h i s t e s t . S e c o n d , s u b j e c t s i n t h e s t a n d a r d W i m m e r - P e r n e r p a r a d i g m may f a i l t o d e m o n s t r a t e t h e i r b e s t u n d e r s t a n d i n g o f t h e p o s s i b i l i t y o f f a l s e b e l i e f s s i m p l y b e c a u s e t h e y a r e p e r s o n a l l y r e m o v e d f r o m t h e a c t i o n o f t h e t h i r d p a r t y s t o r y p r o b l e m s u s e d a nd a r e r e q u i r e d i n s t e a d t o b e p a s s i v e o b s e r v e r s t o a t a l e w h i c h i s a c t e d o u t f o r them u s i n g d o l l f i g u r e s . On t h e s e a n d r e l a t e d g r o u n d s , C h a n d l e r e t a l . ( i n p r e s s ) h a v e a r g u e d t h a t t h e u n e x p e c t e d c h a n g e p a r a d i g m i s a l e s s t h a n o p t i m a l a s s e s s m e n t t o o l f o r d e t e r m i n i n g t h e e a r l i e s t p o i n t a t w h i c h c h i l d r e n e v i d e n c e s u c h a t h e o r y o f m i n d . I n i t s p l a c e t h e y p r o m o t e d an a l t e r n a t i v e p a r a d i g m i n v o l v i n g t h e s t u d y o f d e c e p t i o n i n c h i l d r e n . The r a t i o n a l e f o r t h i s c h o i c e i s d e t a i l e d i n t h e s e c t i o n t h a t f o l l o w s . D e c e p t i o n - P r e r e q u i s i t e s a n d C r i t e r i a C o n s i d e r t h e f o l l o w i n g s c e n e s : I n t h e f a i r y t a l e o f H a n s e l a nd G r e t e l t h e w i c k e d w i t c h i s t r y i n g t o f a t t e n H a n s e l up t o make a t a s t y m e a l . E v e r y d a y s h e a s k s h i m t o s t i c k h i s f i n g e r o u t o f t h e c a g e s o s h e may f e e l how f a t he i s b e c o m i n g . E v e r y d a y , H a n s e l , k n o w i n g t h e w i t c h t o be s h o r t - s i g h t e d , s u b s t i t u t e s a bone f o r h i s f i n g e r i n o r d e r t h a t t h e w i t c h w i l l b e l i e v e h i m t o be t o o t h i n t o make much o f a m e a l . I n d o i n g s o H a n s e l a c h i e v e s t h e d e s i r e d e f f e c t o f p r o l o n g i n g h i s d e m i s e . "Sam" h a s a s p e l l i n g t e s t t o d a y f o r w h i c h he i s u n p r e p a r e d . Sam r e f u s e s t o g e t o u t o f b e d when h i s m o t h e r c a l l s h i m i n t h e m o r n i n g a n d , a l t h o u g h i n t r u t h he f e e l s f i n e , h e c o m p l a i n s t h a t he a c h e s a l l o v e r a n d h i s s t o m a c h i s u p s e t . H i s m o t h e r , n o t k n o w i n g t h a t he h a s a s p e l l i n g t e s t d e c i d e s t h a t Sam s h o u l d s t a y home i n b e d . Sam, l i k e H a n s e l , t h u s p o s t p o n e s a n u n p l e a s a n t e v e n t . The B l a c k - n e c k e d S t i l t ( a member o f t h e s h o r e b i r d f a m i l y ) n o t i c e s a p r e d a t o r n e a r b y w h i c h c o u l d t h r e a t e n i t s e g g s b u t w h i c h t h e b i r d c a n n o t d r i v e away. The S t i l t commences a d i s t r a c t i o n d i s p l a y i n t h e f o r m o f " w i n g - f l a g g i n g " w h i c h p r o d u c e s t h e i m p r e s s i o n o f an i n j u r e d b i r d . The p r e d a t o r f o l l o w s t h e s e e m i n g l y e a s y p r e y a n d t h e n e s t i s l e f t s a f e ( S o r d a h l , 1 9 8 6 ) . A f e m a l e P h o t u r i s f i r e f l y m i m i c s t h e m a t i n g s i g n a l s o f t h e f e m a l e P h o t i n u s f i r e f l y r e s u l t i n g i n t h e a t t r a c t i o n o f a P h o t i n u s m a l e . When t h e m a l e l a n d s a n d a p p r o a c h e s 102 h e r t h e P h o t u r i s f e m a l e a t t a c k s a n d d e v o u r s h i m ( L l o y d , 1 9 8 6 ) . What a l l o f t h e p r e c e d i n g b e h a v i o r a l s e q u e n c e s h a v e i n common i s t h a t some t a r g e t ( p e r s o n , w i t c h , a n i m a l , i n s e c t ) was p e r s u a d e d t o a c t upon some p i e c e o f " m i s i n f o r m a t i o n " . The w i c k e d w i t c h a c t e d a s i f H a n s e l ' s f i n g e r r e a l l y was t o o t h i n . Sam's m o t h e r b a s e d h e r d e c i s i o n t o k e e p Sam a t home on t h e e v i d e n c e a t h a n d , f a l s e t h o u g h i t was. The w o u l d be p r e d a t o r went o f f on a w i l d b i r d c h a s e a nd t h e P h o t i n u s f i r e f l y i n s t e a d o f m a t i n g w i t h a f e m a l e was e a t e n b y one. A l l w e r e d e c e i v e d b u t do t h e a c t i o n s o f t h e one d o i n g t h e m i s l e a d i n g c o n s t i t u t e d e c e p t i o n ? I n t h e c o n t e x t o f a v e r y b r o a d d e f i n i t i o n w h e r e b y d e c e p t i o n i s s i m p l y t h e c a r r y i n g o u t o f m i s l e a d i n g b e h a v i o u r we m i g h t a c c e p t t h e s e a s i n s t a n c e s o f t r u e d e c e i t . To do s o , h o w e v e r , w o u l d be t o r e n d e r t h e c o n c e p t o f d e c e p t i o n a l l b u t d e v o i d o f a n y u s e f u l m e a n i n g . T h e r e e x i s t s t h r o u g h o u t t h e d e c e p t i o n l i t e r a t u r e i n g e n e r a l a w i d e s p r e a d c o n f u s i o n o v e r p r o p e r c r i t e r i a f o r d e c e p t i o n w i t h t h e r e s u l t t h a t t h e s i m p l e , s e e m i n g l y a u t o m a t i c , " g e n e t i c a l l y p r e p r o g r a m m e d " b e h a v i o u r ( M i t c h e l l , 1 9 8 6 ) , s u c h a s t h e f e i n t s a n d r u s e s a s a p p a r e n t i n t h e b r o k e n - w i n g d i s p l a y s o f g r o u n d n e s t i n g b i r d s , a r e o f t e n l u m p e d t o g e t h e r w i t h t h e p r e m e d i t a t e d a c t i o n s o f c h i l d r e n a n d p e r h a p s h i g h e r p r i m a t e s who a t t e m p t t o a v o i d u n p l e a s a n t r i e s b y m a n i p u l a t i n g t h e b e l i e f s o f o t h e r s . G i v e n t h i s c o n f u s i o n o f c r i t e r i a i t w o u l d seem t o be i m p o s s i b l e t o u s e d e c e p t i v e a c t s on t h e p a r t o f a c h i l d a s a way o f i l l u s t r a t i n g 103 t h a t he o r s h e h a s a t h e o r y o f m i n d a s t h e p r e v i o u s s e c t i o n a r g u e s we a r e w a r r a n t e d t o do. C o n s e q u e n t l y , t h e f i r s t s t e p i n any p l a n t o make u s e o f a m e a s u r e o f d e c e p t i o n a s a m a r k e r o f y o u n g c h i l d r e n ' s k n o w l e d g e o f b e l i e f s t a t e s i n o t h e r s i s t o c l e a r l y o u t l i n e w hat s h o u l d be r e q u i r e d o f a n y a c t i o n b e f o r e i t c a n be c l a s s i f i e d a s t r u l y d e c e p t i v e . The f i r s t o f t h e s e f e a t u r e s i s t h a t i n o r d e r t o q u a l i f y a s t r u l y d e c e p t i v e s u c h a c t i o n s must o c c u r w i t h i n a s o c i a l c o n t e x t r e q u i r i n g t h e a c t i v e p a r t i c i p a t i o n o f b o t h d e c e i v e r s a n d t h e t a r g e t s o f t h e i r d e c e i t ( M i t c h e l l & Thompson, 1 9 8 6 ) . D e c e p t i o n c a n be s a i d t o o c c u r a s a r e s u l t o f a s u c h d y n a m i c i n t e r a c t i o n s w h e n e v e r t h e d e c e i v e r somehow m a n i p u l a t e s t h e b e l i e f s o f t h e o t h e r i n s u c h a way a s t o p r o d u c e i n them a r e p r e s e n t a t i o n o f r e a l i t y t h a t d o e s n o t c o r r e s p o n d w i t h t h e s t a t e o f t h e w o r l d a s t h e d e c e i v e r b e l i e v e s i t t o be. C o n s e q u e n t l y , t o be s u c c e s s f u l d e c e p t i o n , l i k e o t h e r t y p e s o f c o m m u n i c a t i o n , must o c c u r w i t h i n a s y s t e m o f s h a r e d m e a n i n g (Mawby & M i t c h e l l , 1986) w h e r e b o t h t h e d e c e i v e r and t h e t a r g e t m u s t s h a r e a common u n d e r s t a n d i n g o f what g i v e n s i g n s a r e n o r m a l l y t a k e n t o s i g n i f y . I f S a l l y ' s f a t h e r t e l l s h e r t o b r u s h h e r t e e t h b e f o r e g o i n g o u t t o p l a y , b u t S a l l y i s i n a h u r r y t o be w i t h h e r f r i e n d s a n d d o e s n ' t want t o t a k e t h e t i m e , s h e m i g h t t r y t o d e c e i v e h e r f a t h e r b y s i m p l y w e t t i n g h e r t o o t h b r u s h , d e m o n s t r a t i n g h e r b e l i e f t h a t h e r f a t h e r s h a r e s h e r u n d e r s t a n d i n g t h a t i n t h e n o r m a l c o u r s e o f e v e n t s , a wet t o o t h - b r u s h s i g n i f i e s r e c e n t l y b r u s h e d t e e t h . W i t h o u t s u c h a s h a r e d m e a n i n g t h i s d e c e p t i o n c o u l d n o t 104 t a k e p l a c e . I m a g i n e f u r t h e r t h a t a M a r t i a n , o n whose p l a n e t t h e r e i s no w a t e r a nd s o f o r whom a wet t o o t h b r u s h i s n o t a s i g n f o r c l e a n t e e t h , i s g i v e n t h e r e s p o n s i b i l i t y f o r e n s u r i n g t h a t S a l l y h a s b r u s h e d h e r t e e t h . I n t h i s c a s e S a l l y ' s t o o t h b r u s h w e t t i n g w o u l d t h e n be f u t i l e a s a d e c e p t i v e s t r a t e g y b e c a u s e S a l l y a n d t h e M a r t i a n w o u l d l a c k a common g r o u n d o f s h a r e d m e a n i n g . S a l l y w o u l d h a v e no M a r t i a n f o l k - p s y c h o l o g y ( D e n n e t t , 1985, 1987) w i t h w h i c h t o p r e d i c t a n d t o m a n i p u l a t e t h e M a r t i a n ' s t h o u g h t s a n d a c t i o n s . On s i m i l a r g r o u n d s i t c o u l d b e a r g u e d f o r e a c h o f o u r e x a m p l e s a t t h e b e g i n n i n g o f t h i s s e c t i o n ( H a n s e l a n d W i t c h ; Sam and m o t h e r ; b i r d a n d p r e d a t o r ; f i r e f l i e s ) t h a t some s o r t o f d y n a m i c i n t e r a c t i o n t o o k p l a c e . A l l i n v o l v e some i n i t i a t i o n o f i n t e r a c t i o n o r d i a l o g u e b y one p a r t y a n d a r e s p o n s e b y t h e o t h e r . What i s l e s s t h a n c l e a r , h o w e v e r , i s w h e t h e r a l l o f t h e s e e x a m p l e s i n v o l v e a s y s t e m o f s h a r e d m e a n i n g . I n t h e c a s e o f t h e f i r e f l i e s , f o r e x a m p l e , one m i g h t r e a s o n a b l y c o n t e n d t h a t w h i l e t h e m essage t h e f e m a l e i s s e n d i n g may h o l d t h e c l e a r m e a n i n g o f a m a t i n g c a l l t o t h e m a l e , i t m i g h t h o l d t h e e n t i r e l y d i f f e r e n t b u t e q u a l l y c l e a r m e a n i n g t o t h e f e m a l e t h a t d i n n e r i s i n s i g h t w i t h o u t i m p l y i n g any u n d e r s t a n d i n g on h e r p a r t t h a t t h e s i g n a l w i l l be m i s i n t e r p r e t e d a s a m a t i n g message b y t h e m a l e o f t h e o t h e r g e n u s . I n a d d i t i o n t o b e i n g embedded w i t h i n a s o c i a l i n t e r a c t i o n a n d b a s e d o n a s y s t e m o f s h a r e d m e a n i n g , a t h i r d p r e r e q u i s i t e f o r d e c e p t i o n i s t h a t t h e r e must e x i s t b e t w e e n t h e two p a r t i c i p a n t s 105 some c o n d i t i o n o f d i f f e r e n t i a l a c c e s s t o r e l e v a n t i n f o r m a t i o n w h i c h t h e p o t e n t i a l d e c e i v e r r e c o g n i z e s . T h a t i s , y o u a r e n o t l i k e l y t o be a b l e t o d e c e i v e me i f a l l o f t h e i n f o r m a t i o n I n e e d i n d e c i d i n g how t o a c t i s a l r e a d y a v a i l a b l e t o me. J u s t a s i m p o r t a n t l y t h e d e c e i v e r n e e d s a l s o t o r e c o g n i z e a n d be p r e p a r e d t o c a p i t a l i z e o n t h i s d i f f e r e n t i a l d i s t r i b u t i o n o f r e l e v a n t f a c t s . On t h e s t r e n g t h o f t h i s r e q u i r e m e n t i t w o u l d seem t h a t t h e a b i l i t y t o d e c e i v e r e q u i r e s a s a p r e r e q u i s i t e F l a v e l l ' s ( 1 9 7 8 ) l e v e l 1 v i s u a l p e r s p e c t i v e t a k i n g a b i l i t y i n w h i c h t h e c h i l d u n d e r s t a n d s t h a t o t h e r p e r s o n s who h a v e a c c e s s t o f e w e r o r d i f f e r e n t f a c t s w i l l a r r i v e a t a d i f f e r e n t u n d e r s t a n d i n g . I t i s o n l y when t h i s r e c o g n i t i o n o f d i f f e r e n t i a l a c c e s s i s p r e s e n t t h a t t h e a c t o r h a s t h e o p p o r t u n i t y t o i n f o r m , n o t t o i n f o r m , o r t o m i s i n f o r m o t h e r s ( V a s e k , 1 9 8 6 ) . D e n n e t t ( 1 9 8 7 ) i l l u s t r a t e s t h e d i f f i c u l t i e s i n v o l v e d i n a s s e s s i n g s u c h k n o w l e d g e i n a p o t e n t i a l d e c e i v e r b y u s i n g a s an e x a m p l e t h e p r o b l e m s t h a t m i g h t b e e n c o u n t e r e d i n a t t e m p t i n g t o s e t up a s i t u a t i o n i n w h i c h a v e r v e t monkey i s a f f o r d e d t h e o p p o r t u n i t y t o w i t h h o l d i n f o r m a t i o n a b o u t an a p p r o a c h i n g p y t h o n f r o m a r i v a l v e r v e t monkey. The m a j o r d i f f i c u l t i e s i n v o l v e d i n t h i s i n s t a n c e a r e t w o - f o l d . The o b s e r v e r c a n n o t b e c e r t a i n t h a t t h e f i r s t v e r v e t h a s a c t u a l l y s e e n t h e p y t h o n n o r c a n t h e o b s e r v e r be c e r t a i n t h a t t h e v e r v e t t h i n k s t h a t i t s r i v a l h a s n ' t s e e n i t . I n t h i s c a s e s i m p l e f a i l u r e t o i n f o r m on t h e p a r t o f t h e f i r s t v e r v e t c a n a l w a y s b e e x c u s e d b y t h e c l a i m o f i g n o r a n c e . On t h e s e g r o u n d s D e n n e t t a r g u e s t h a t a m i n i m a l l y c o m p l e x e x p e r i m e n t a l p a r a d i g m f o r 106 d e t e r m i n i n g w h e t h e r d e c e p t i o n h a s t a k e n p l a c e w o u l d n e e d t o i n c l u d e e v i d e n c e t h a t t h e d e c e i v e r h a s a c t u a l l y u n d e r t a k e n t o a c t i v e l y m i s i n f o r m h i s r i v a l i n some way. F i n a l l y , g i v e n a l l o f t h e a b o v e m e n t i o n e d p r e r e q u i s i t e c o n d i t i o n s , t h e f i n a l l e a v e n i n g i n g r e d i e n t n e c e s s a r y t o t u r n s u c h a m i x t u r e i n t o a d e c e p t i v e a c t i s t h e d e f i n i t e i n t e n t i o n t o m i s i n f o r m . An a c t o r ' s u n d e r s t a n d i n g t h a t he o r s h e e x i s t s i n some i n t e r a c t i o n w i t h a common l a n g u a g e p a r t n e r who h a s d i f f e r e n t i a l a c c e s s t o e s s e n t i a l i n f o r m a t i o n s i m p l y p r o v i d e s h i m o r h e r w i t h t h e o p p o r t u n i t y t o d e c e i v e o r n o t t o d e c e i v e . I t i s t h i s r e q u i r e m e n t t h a t d e c e p t i v e a c t s must be c a r r i e d o u t p u r p o s e f u l l y t h a t c o n s t i t u t e s t h e c e n t r a l c r i t e r i a t h a t s e p a r a t e s many more p r i m i t i v e t y p e s o f m i s l e a d i n g m e s s a g e s s u c h a s t h a t o f t h e f e m m e - f a t a l e f i r e f l i e s , f r o m w h a t a r e g e n e r a l l y a g r e e d u p o n as t r u l y d e c e p t i v e a c t s ( A n d e r s o n , 1986; C h e v a l i e r - S k o l n i k o f f , 1986; M i t c h e l l , 1986; Russow, 1 9 8 6 ) . T h i s i n c l u s i o n o f i n t e n t i o n a l i t y i n t h e c r i t e r i a o f d e c e p t i o n h a s t h e c l a r i f y i n g c o n s e q u e n c e o f a l l o w i n g us t o e x c l u d e t h o s e c a s e s w h i c h a p p e a r t o i n v o l v e o n l y i n n a t e o r c h a r a c t e r i s t i c ways o f r e s p o n d i n g b e h a v i o r a l l y i n a s e t s t e r e o t y p i c way i n a s p e c i f i c s i t u a t i o n . W h i l e t h e S t i l t ' s " b r o k e n - w i n g " d i s p l a y may be e f f e c t i v e i n l e a d i n g t h e p r e d a t o r away f r o m t h e n e s t and a s s u c h i s c e r t a i n l y m i s l e a d i n g , t h e f a c t t h a t t h e same b e h a v i o u r o c c u r s i n t h e same s o r t s o f s i t u a t i o n s a c r o s s many s p e c i e s o f g r o u n d n e s t i n g b i r d s s u g g e s t s t h a t i t i s u n l i k e l y t h a t t h e i n d i v i d u a l b i r d s a r e a c t i n g w i t h any p l a n o r i n t e n t i o n i n m i n d . R a t h e r one m i g h t s a y t h a t 107 t h i s s o r t o f a u t o m a t i c b e h a v i o u r w h i c h h a s t h e r e s u l t o f c a u s i n g a n o t h e r t o h a v e a f a l s e b e l i e f i s i n some s e n s e p r e p r o g r a m m e d i n t o t h e o r g a n i s m ' s r e s p o n s e r e p e r t o i r e a n d c o n s e q u e n t l y c a n n o t be c o n s i d e r e d i n t e n t i o n a l . T h i s s i m p l e n o t i o n o f i n t e n t i o n a l i t y a s p l a n f u l a c t i o n on t h e p a r t o f a d e c e i v e r s t i l l r e m a i n s i n s u f f i c i e n t , h o w e v e r , f o r any f u l l y s a t i s f a c t o r y d e f i n i t i o n o f d e c e p t i o n . D e n n e t t ' s w e l l known e x a m p l e o f t h e d o g who r u n s t o t h e d o o r s o t h a t i t s m a s t e r w i l l l e a v e i t s f a v o r i t e c h a i r i s i l l u s t r a t i v e o f w h a t i s l a c k i n g i n t h i s u n e l a b o r a t e d n o t i o n o f i n t e n t i o n a l i t y . The d o g may be a c t i n g i n t e n t i o n a l l y b y g o i n g t o t h e d o o r . I t may h a v e p l a n n e d i t s a c t i o n s w i t h t h e u n d e r s t a n d i n g t h a t i f i t went t o t h e d o o r i t s m a s t e r w o u l d v a c a t e i t s f a v o r i t e c h a i r . B u t was t h e dog o p e r a t i n g i n t e n t i o n a l l y w i t h r e f e r e n c e t o i t s m a s t e r ' s b e l i e f s ? D i d t h e d o g i n t e n t i o n a l l y t r y t o s e d u c e i t s m a s t e r i n t o h o l d i n g t h e f a l s e b e l i e f t h a t h e , t h e d o g , w i s h e d t o go o u t s i d e , t h e r e b y c a u s i n g i t s m a s t e r t o go t o t h e d o o r t o l e t i t o u t ? D e n n e t t s u g g e s t s t h a t a l t h o u g h t h e d o g ' s a c t i o n s w e r e m i s l e a d i n g a s i n t e r p r e t e d b y t h e m a s t e r , u n l e s s we c a n c l e a r l y show t h a t t h e d o g ' s a c t i o n was c a r r i e d o u t w i t h t h e i n t e n t i o n o f m a n i p u l a t i n g i t s m a s t e r ' s b e l i e f , t h a t i s w i t h d e c e p t i v e i n t e n t , i t c a n n o t b e c o n s i d e r e d t r u l y d e c e p t i v e . Thus a f u r t h e r c o d i c i l t o t h e r e q u i r e m e n t t h a t a p o t e n t i a l d e c e i v e r must be a c t i n g i n t e n t i o n a l l y i s t h a t he o r s h e must a l s o i n t e n d f o r t h e t a r g e t t o t a k e a s t r u e a m e s s a g e t h a t he o r s h e b e l i e v e s t o be f a l s e ( V a s e k , 1 9 8 6 ) . W i t h o u t t h i s a d d i t i o n t o o u r 108 i n c l u s i o n c r i t e r i a i t would be impossible to exclude those cases where an actor may i n t e n t i o n a l l y send a message which has the re s u l t of misleading another but which was based on the actor's own mistaken b e l i e f rather than any intent to deceive. F i n a l l y , i t i s necessary to add to a l l the c r i t e r i a already l i s t e d the requirement that the perpetrator of any candidate act of deception must also recognize that he or she i s deceiving the other. Consider the o r i g i n a l radio broadcast of Orson Wells' "War of the Worlds". Although the broadcasting station announced a disclaimer at the beginning of the program that what people were about to hear was i n fact purely f i c t i o n a l , the broadcast was so r e a l i s t i c i n i t s format and delivery that a great number of people who tuned i n part-way through a c t u a l l y believed that the Martians had landed and panic ensued. In spite of the great number of people who were deceived by t h i s radio account no r e a l deception can be claimed. Although the producers of the show c l e a r l y intended f o r t h e i r audience to hear the r e a l i s t i c account of Martians landing on Earth they did not intend f o r the audience to hold a f a l s e b e l i e f about the broadcast being true as they had provided a cl e a r marker that the program was f i c t i o n and only an " a s - i f " scenario. It i s the presence of just such disclamatory markers that separates f i c t i o n a l works, humour and indeed pretend s o c i a l play i n young children from deception. The young c h i l d who says to an adult (or another child) " l e t ' s pretend that these rocks are cookies" i s often quick to add "but they're not r e a l l y cookies" i n case the other person hasn't heard or may not 109 u n d e r s t a n d t h e m a r k e r " l e t ' s p r e t e n d " . Thus i n o r d e r f o r a c h i l d t o p r o v i d e e v i d e n c e t h a t he o r s h e c o u l d make u s e o f d e c e p t i v e s t r a t e g i e s n o t o n l y i s i t n e c e s s a r y t o i n s t i l l f a l s e b e l i e f i n a n o t h e r b u t t h e c h i l d h a s t o i n t e n d t h a t t h e o t h e r w i l l m i s t a k e n l y b e l i e v e t o be t r u e what t h e c h i l d b e l i e v e s t o b e f a l s e . T h a t i s , a p o t e n t i a l d e c e i v e r must a p p r e c i a t e t h a t he o r s h e i n t e n d s f o r t h e p o t e n t i a l v i c t i m o f t h e d e c e i t t o m i s t a k e n l y j u d g e t h e f a l s e m e ssage a s a d e p i c t i o n o f t h e t r u e s t a t e o f a f f a i r s . G i v e n a l l t h a t h a s b e e n s a i d a b o v e , a c t s o f d e c e p t i o n , t h e n , c a n be d e f i n e d a s a c t i o n s t h a t t a k e p l a c e i n t h e c o n t e x t o f s o c i a l i n t e r a c t i o n s a n d s y s t e m s o f s h a r e d m e a n i n g a nd when t h e d e c e i v e r a n d h i s o r h e r i n t e n d e d v i c t i m h a v e d i f f e r e n t i a l a c c e s s t o t h e f a c t s . G i v e n t h e s e c o n d i t i o n s , d e c e p t i o n c a n be c h a r a c t e r i z e d a s a p l a n f u l a c t i o n w h i c h i s c a r r i e d o u t w i t h t h e i n t e n t i o n o f m a n i p u l a t i n g a n o t h e r ' s b e l i e f s s o t h a t t h e o t h e r t a k e s t o be t r u e what t h e s e l f b e l i e v e s t o be f a l s e . The u s e f u l n e s s o f d e c e p t i o n as a way o f i n d e x i n g t h e p r e s e n c e o f some t h e o r y o f m i n d was s u g g e s t e d b y P r e m a c k and W o o d r u f f ( 1 9 7 8 ) i n t h e i r e f f o r t s t o d e t e r m i n e w h e t h e r c h i m p a n z e e s i m p u t e m e n t a l s t a t e s t o t h e m s e l v e s a n d o t h e r s . B a s e d on t h i s w o r k and t h e r e s p o n s e s i t g e n e r a t e d ( e . g . D e n n e t t , 1978) Wimmer an d P e r n e r ( 1 9 8 3 ) h a v e a l s o m a i n t a i n e d t h a t d e c e p t i v e a c t i o n i s a good i n d e x o f t h e p o s s e s s i o n o f a t h e o r y o f m i n d due t o t h e f a c t t h a t i n h e r e n t i n t h e p l a n f o r d e c e i t i s t h e r e a l i z a t i o n t h a t a n o t h e r may b e m i s l e d t o b e l i e v e s o m e t h i n g w h i c h i s f a l s e . Thus 110 t h e s e a u t h o r s a n d o t h e r s ( C h e v a l i e r - S k o l n i k o f f , 1986; V a s e k , 1986) s u g g e s t t h a t d e c e p t i o n r e q u i r e s t h e p r e s e n c e o f s e c o n d o r d e r b e l i e f s a n d c o n s e q u e n t l y some t h e o r y o f m i n d . I n s p i t e o f i t s p o t e n t i a l u t i l i t y a s an i n d e x o f c h i l d r e n ' s b e l i e f s a b o u t t h e b e l i e f s o f o t h e r s , t h e f e w meas u r e m e n t p r o c e d u r e s w h i c h h a v e b e e n b a s e d on d e c e p t i v e p r a c t i c e s t y p i c a l l y h a v e shown a l a t e e m e r g e n c e . Wimmer a n d P e r n e r ( 1 9 8 3 ) p o i n t o u t t h a t w h i l e t h e n a t u r a l o c c u r r e n c e o f d e c e p t i o n w o u l d s t r o n g l y i n d i c a t e m e t a r e p r e s e n t a t i o n a b i l i t i e s , t h e y a l s o m a i n t a i n e d t h a t r e l y i n g u p o n d e c e p t i o n a s a m e a s u r e o f f a l s e - b e l i e f u n d e r s t a n d i n g w o u l d u n d e r e s t i m a t e t h i s a b i l i t y due t o t h e a d d i t i o n a l p l a n n i n g s t e p s w h i c h , a c c o r d i n g t o t h e s e a u t h o r s , make t h e c a r r y i n g - o u t o f d e c e p t i o n a more d i f f i c u l t e n d e a v o u r t h a n t h e p a s s i v e u n d e r s t a n d i n g o f f a l s e b e l i e f . W h i l e t h e r e a r e f e w r e l e v a n t s t u d i e s o f d e c e p t i o n i n c h i l d r e n , m o s t t h a t h a v e b e e n c a r r i e d o u t f a l l i n t o one o f t w o m a j o r a r e a s : t h e p a s s i v e r e p o r t i n g o f a n u n d e r s t a n d i n g o f d e c e i t i n o t h e r s ; o r t h e p r o d u c t i o n o f d e c e i t w i t h i n t h e c o n t e x t o f a c o m p e t i t i v e game. N e i t h e r o f t h e s e t y p e s o f t a s k s a r e p e r f o r m e d s u c c e s s f u l l y b y s u b j e c t s y o u n g e r t h a n 5 y e a r s o f age. I n t h o s e s t u d i e s w h e r e s u b j e c t s a r e r e q u i r e d t o c o m p r e h e n d d e c e p t i v e p l o y s o r t o p r e d i c t t h e c o n s e q u e n t b e l i e f s o f s t o r y c h a r a c t e r s who h a d b e e n l i e d t o b y a n o t h e r , most c h i l d r e n do n o t s u c c e e d u n t i l a p p r o x i m a t e l y 5 t o 6 y e a r s o f age o r o l d e r ( e . g . V a s e k , 1986; Wimmer, G r u b e r & P e r n e r , 1984, 1985; Wimmer & P e r n e r , 1 9 8 3 ) . S i m i l a r l y s t u d i e s u s i n g c o m p e t i t i v e game p r o c e d u r e s ( e . g . S e l m a n , 1980; S h u l t z & C l o g h e s y , 1981) i n w h i c h c h i l d r e n must a n t i c i p a t e t h e i r o p p o n e n t ' s b e l i e f s , n o t o n l y a b o u t t h e i n f o r m a t i o n a t h a n d b u t a l s o t h e i r o p p o n e n t ' s b e l i e f s a b o u t t h e i r b e l i e f s a b o u t t h e i r o p p o n e n t ' s b e l i e f s , i t h a s b e e n d e m o n s t r a t e d t h e s u b j e c t s do n o t s u c c e s s f u l l y u s e d e c e p t i v e s t r a t e g i e s o n a c o n s i s t e n t b a s i s u n t i l t h e y a r e o l d e r t h a n 5 y e a r s o f age. More r e c e n t l y t h e r e h a v e b e e n two s t u d i e s c a r r i e d o u t i n d e p e n d e n t l y t h a t e x a m i n e y o u n g c h i l d r e n ' s a b i l i t y t o d e c e i v e . I n a s t u d y o f d e c e p t i o n i n p r e s c h o o l c h i l d r e n c a r r i e d o u t b y L a F r e n i e r e ( 1 9 8 8 ) s u b j e c t s w e r e i n s t r u c t e d t o " t r y t o f o o l " an e x p e r i m e n t e r a b o u t t h e l o c a t i o n o f an o b j e c t . R a t h e r t h a n r e l y i n g u p o n c h i l d r e n ' s own s t r a t e g i e s f o r d e c e p t i o n , h o w e v e r , c h i l d r e n w e r e e x p e c t e d t o v e r b a l l y l i e w h i l e b e i n g f a c e d w i t h a n a d u l t e x p e r i m e n t e r who i n t e r r o g a t e d them w h i l e s t a r i n g s t r a i g h t i n t h e i r e y e s . U n d e r t h e s e somewhat i n t i m i d a t i n g c i r c u m s t a n c e s 3 - y e a r - o l d s w e r e n o t p r o f i c i e n t a t c o n c e a l i n g t h e t r u e l o c a t i o n o f t h e o b j e c t . I n c o n t r a s t , L e w i s , S t r a n g e r a n d S u l l i v a n ( 1 9 8 9 ) f o u n d t h a t when 3 - y e a r - o l d s v i o l a t e d a p r o h i b i t i o n , 3 8 % s p o n t a n e o u s l y l i e d a b o u t t h e i r a c t i o n s a n d a f u r t h e r 2 4 % r e f u s e d t o a n s w e r t h e e x p e r i m e n t e r . W h i l e i f i s e n c o u r a g i n g t h a t 6 2 % o f t h e s e y o u n g s u b j e c t s a t a minimum w i t h h e l d i n f o r m a t i o n w i t h o u t any i n d u c e m e n t t o do s o , i t r e m a i n s d i f f i c u l t t o u n a m b i g u o u s l y i n t e r p r e t t h e r e s p o n s e s o f t h o s e s u b j e c t s who s i m p l y r e m a i n e d s i l e n t . A s D e n n e t t ( 1 9 7 8 ) p o i n t s o u t what i s n e e d e d i s a p r o c e d u r e w h i c h r e q u i r e s s u b j e c t s t o a c t i v e l y t a k e s t e p s t o d e c e i v e . S u c h a p r o c e d u r a l p a r a d i g m w i l l b e p r e s e n t e d i n t h e 112 f o l l o w i n g s e c t i o n . The D e c e p t i o n P a r a d i g m G i v e n t h e s e r i e s o f p o t e n t i a l a d v a n t a g e s o f u s i n g d e c e p t i o n a s a m a r k e r o f f a l s e b e l i e f s C h a n d l e r , F r i t z a n d H a l a ( i n p r e s s ) r e c e n t l y t u r n e d t o t h e u s e o f d e c e p t i o n a s a way o f d e t e r m i n i n g t h e e a r l i e s t age a t w h i c h y o u n g c h i l d r e n f i r s t e n t e r t a i n b e l i e f s a b o u t t h e b e l i e f s o f o t h e r s . T h i s r e s e a r c h p a r a d i g m was d e v e l o p e d i n r e s p o n s e t o w h a t was c o n s i d e r e d b y t h e a u t h o r s t o be t h e s y s t e m a t i c u n d e r a p p r e c i a t i o n o f 3 - y e a r o l d s ' a b i l i t i e s i n u n d e r s t a n d i n g t h e n a t u r e o f c o u n t e r f a c t u a l b e l i e f s i n o t h e r s r e s u l t i n g f r o m s t a n d a r d u n e x p e c t e d c h a n g e m e a s u r e s ( e . g . , P e r n e r , Leekam & Wimmer, 1987; Wimmer & P e r n e r , 1 9 8 3 ) . C o n s e q u e n t l y , t h e i r " d e c e p t i o n " p a r a d i g m was d e s i g n e d t o c i r c u m v e n t a number o f t h e p r o c e d u r a l s h o r t c o m i n g s i n h e r e n t i n more f a m i l i a r u n e x p e c t e d c h a n g e t a s k s w h i l e i n c o r p o r a t i n g t h e e s s e n t i a l f e a t u r e o f t h e s e b y h o l d i n g t o some d e m o n s t r a t i o n o f c h i l d r e n ' s u n d e r s t a n d i n g o f c o u n t e r f a c t u a l s i n o t h e r p e r s o n s a s e s s e n t i a l e v i d e n c e f o r a n e m e r g i n g t h e o r y o f m i n d . I n p a r t i c u l a r , t h e d e c e p t i o n p a r a d i g m e m p l o y e d b y C h a n d l e r e t a l . d i f f e r s f r o m t h e s t a n d a r d Wimmer-P e r n e r u n e x p e c t e d c h a n g e p a r a d i g m a l o n g s e v e r a l i m p o r t a n t d i m e n s i o n s c o n c e r n i n g t h e c o m p l e x i t y o f t h e t a s k a n d r o l e o f t h e s u b j e c t s . R a t h e r t h a n b e i n g a s k e d t o r e s p o n d t o t e s t q u e s t i o n s a f t e r p a s s i v e l y l i s t e n i n g t o a c o m p l i c a t e d n a r r a t i v e , s u b j e c t s i n t h i s d e c e p t i o n p r o c e d u r e w e r e i n v o l v e d i n a h i d e - a n d - s e e k game w h i c h l e f t t h e m o p p o r t u n i t i e s t o a t t e m p t t o i n d u c e f a l s e b e l i e f s i n a n o t h e r . The v e r b a l i n s t r u c t i o n s r e q u i r e d b y t h i s p r o c e d u r e are minimal, p a r t i c i p a n t s are r e a l persons rather than d o l l f igures , and subjects play an act ive ro l e i n manipulating the b e l i e f s of another. More s p e c i f i c a l l y , the subjects of t h i s procedure are introduced to a hide-and-seek board game invo lv ing the c h i l d and two adult experimenters. One experimenter (El) remains with the c h i l d throughout the procedure to remind him or her of the goals and rules of the game, to p h y s i c a l l y a s s i s t with h id ing attempts and to probe for j u s t i f i c a t i o n s fo l lowing the c h i l d ' s act ions . The second experimenter (E2) e s s e n t i a l l y acts as an opponent to the subject and E l . The game cons is ts of several h id ing and f ind ing t r i a l s invo lv ing a small "treasure" which i s to be hidden i n one of f i v e closed opaque containers l i n e d up along one end of the board. The board i t s e l f i s covered with o i l c l o t h provid ing a smooth washable p lay ing surface. The i n i t i a l t r i a l s involve an attempt to f a m i l i a r i z e subjects with the materials and to see i f they can make use of or at l eas t understand t e l l - t a l e clues such as misaligned containers or l i d s i n t h e i r search for the treasure, and whether they take steps to avoid leaving such clues i n t h e i r own h id ing e f f o r t s . Once subjects seem reasonably comfortable with the game they are introduced to a puppet named Toni whose feet are mounted on a revolv ing wheel and who can be manipulated by a handle to move across the board. The treasure i s sa id to belong to Toni and the goal of the task as one i n which the subject i s asked to help Toni hide the treasure so that E2 w i l l not f i n d i t . This i s not easy as Toni ' s feet secrete paint leaving inky foo tpr in t s wherever Toni walks. Subjects are then encouraged to hide the treasure i n as many d i f f e r e n t ways as they can th ink of to make i t d i f f i c u l t f or E2 to f i n d . When E2 returns to the room af ter each t r i a l , i f the subject had attempted any type of manipulation of the evidence regarding the loca t ion of the treasure E2 was s igna l l ed not to f i n d i t on the f i r s t t r i a l . Subjects were also given the opportunity to t e l l the t r u t h or l i e about the l oca t ion of the treasure when E2 f a i l e d to f i n d i t on the f i r s t t r y . Using t h i s deception paradigm Chandler et a l . found that even 2 1/2 -year o ld c h i l d r e n were capable of deceiving others, c l e a r l y supporting the early-onset view that before 3 years of age c h i l d r e n are capable of enter ta in ing b e l i e f s about the fa l s e b e l i e f s of others. On the bas is of these r e s u l t s i t would appear that i t may not be the a b i l i t y to understand fa l s e b e l i e f s per se that has evaded most 3-year o ld subjects i n the standard Wimmer-Perner paradigm, but rather t h e i r a b i l i t y to comment upon such higher order b e l i e f s when queried about t h i r d party story characters engaged i n a computationally complex narrat ive sequence. Test ing t h i s prospect was the main purpose of the study discussed i n the attached research report . Before attempting to determine exact ly which of the dimensions which separate the Chandler et a l . deception measure from the Wimmer-Perner tes t of fa l s e b e l i e f s add i t i ona l questions must be asked as to the actual magnitude of d i f ferences found. S p e c i f i c a l l y what needs to be determined i s whether the re su l t s 115 o f t h e C h a n d l e r e t a l . s t u d y a r e n o t due t o t h e i r h a v i n g t e s t e d a s p e c i a l p o p u l a t i o n who, h a d t h e y b e e n g i v e n t h e u n e x p e c t e d c h a n g e m e a s u r e o f f a l s e b e l i e f u n d e r s t a n d i n g , m i g h t h a v e p e r f o r m e d a d e q u a t e l y o n t h a t t a s k a s w e l l . M o s t o f t h e w o r k u s i n g t h e u n e x p e c t e d c h a n g e p a r a d i g m h a s b e e n c a r r i e d o u t u s i n g s a m p l e s o f A u s t r i a n a n d E n g l i s h c h i l d r e n . Some m i n o r d i f f e r e n c e s h a v e b e e n f o u n d b e t w e e n t h e two c o u n t r i e s w i t h E n g l i s h c h i l d r e n p e r f o r m i n g somewhat b e t t e r t h a n A u s t r i a n ( P e r n e r , Leekam & Wimmer, 1 9 8 7 ) . C o n s e q u e n t l y , t h e q u e s t i o n r e m a i n s a s t o w h e t h e r C a n a d i a n c h i l d r e n m i g h t e x h i b i t e v e n h i g h e r p e r f o r m a n c e l e v e l s on t h e t a s k . I n o r d e r t o t e s t f o r t h e p o s s i b i l i t y t h a t s u c h s a m p l e d i f f e r e n c e s may h a v e c a u s e d t h e d i s p a r i t y b e t w e e n f i n d i n g s b a s e d on t h e s e two p a r a d i g m s w h a t i s r e q u i r e d i s t o p r o v i d e a d i r e c t w i t h i n - s u b j e c t c o m p a r i s o n o f t h e d e c e p t i o n a n d t h e u n e x p e c t e d c h a n g e p a r a d i g m s a c r o s s t h e same t h r e e a ge g r o u p s . The p r o p o s e d s t u d y w i l l a s s e s s c h i l d r e n ' s u n d e r s t a n d i n g o f f a l s e b e l i e f u s i n g b o t h t h e s t a n d a r d u n e x p e c t e d c h a n g e t a s k a n d t h e n e w l y d e v e l o p e d d e c e p t i o n t a s k . S u b j e c t s w i l l r a n g e i n age f r o m 3.0 y e a r s t o 4.5 y e a r s t o i n c l u d e t h e age w h i c h i s c o n s i d e r e d b y P e r n e r e t a l . ( 1 9 8 7 ) t o be t h e l o w e r age b o u n d a r y f o r u n d e r s t a n d i n g f a l s e b e l i e f . I t i s e x p e c t e d t h a t , i n l i n e w i t h t h e f i n d i n g s o f P e r n e r e t a l . ( 1 9 8 7 ) , p e r f o r m a n c e on t h e u n e x p e c t e d c h a n g e t a s k w i l l i m p r o v e w i t h age b u t w i t h t h e m a j o r i t y o f c h i l d r e n who a r e l e s s t h a n 3 1/2 y e a r s s t i l l d e m o n s t r a t i n g a n i n a b i l i t y t o c o r r e c t l y a n s w e r t h e f a l s e - b e l i e f t e s t q u e s t i o n s . By c o n t r a s t , e v e n t h e y o u n g e s t s u b j e c t s t o be t e s t e d a r e e x p e c t e d t o make u s e o f d e c e p t i v e s t r a t e g i e s i n t h e C h a n d l e r e t a l . t a s k . Any d i s c r e p a n c y f o u n d b e t w e e n t h e r e s u l t s o f t h e s e two t e s t i n g p r o c e d u r e s i s e x p e c t e d t o f a v o u r t h e d e c e p t i o n t a s k w h i c h i s h y p o t h e s i z e d t o be e a s i e r t h a n t h e u n e x p e c t e d c h a n g e t a s k f o r t h e s e y o u n g s u b j e c t s . APPENDIX B 117 PROTOCOL FOR UNEXPECTED CHANGE TASK S u b j e c t s a r e b r o u g h t i n t o t h e t e s t i n g room w h e r e t h e p u p p e t s a n d m a t e r i a l s a r e s e t up as shown i n f i g u r e 1. The p r o c e d u r e i s i n t r o d u c e d b y t h e e x p e r i m e n t e r : "Today y o u a r e g o i n g t o s e e a s h o r t p u p p e t show. W a t c h c a r e f u l l y b e c a u s e I am g o i n g t o a s k y o u some q u e s t i o n s a f t e r i t i s o v e r . " The two p u p p e t s a r e i n t r o d u c e d : " T h i s i s K a t i e a n d t h i s i s Sam. They a r e f r i e n d s a t s c h o o l a n d l i k e t o p l a y t o g e t h e r . R i g h t now t h e y a r e p l a y i n g w i t h a t o y c a r . They t a k e t u r n s p l a y i n g w i t h t h i s c a r . " The p u p p e t s a r e shown t o p l a y w i t h t h e c a r . "Then t h e y h e a r t h e i r t e a c h e r c a l l i n g them " K a t i e , Sam, t i m e t o c l e a n up and come t o s n a c k . " K a t i e a n d Sam l o o k a r o u n d f o r a p l a c e t o p u t t h e t o y c a r s o t h e y c a n come b a c k t o p l a y w i t h i t l a t e r . S o m e t i m e s t h e y p u t i t i n t h e r e d c o n t a i n e r a n d s o m e t i m e s t h e y p u t i t i n t h e y e l l o w c o n t a i n e r . R i g h t now t h e y p u t i t i n t h e y e l l o w one. " The p u p p e t s a r e shown t o g e t h e r p u t t i n g t h e t o y c a r i n t h e y e l l o w c o n t a i n e r . "Then b o t h K a t i e a n d Sam l e a v e f o r s n a c k . " The p u p p e t s a r e shown t o l e a v e t h e room i n o p p o s i t e d i r e c t i o n s " K a t i e f i n i s h e s h e r s n a c k f i r s t a n d comes b a c k t o p l a y w i t h t h e t o y c a r . She t a k e s i t o u t o f t h e y e l l o w c o n t a i n e r a n d s t a r t s t o p l a y w i t h i t a g a i n . B u t t h e n s h e h e a r s h e r t e a c h e r c a l l i n g a g a i n , " K a t i e , y o u d i d n ' t c l e a n up y o u r s n a c k t h i n g s , p l e a s e come b a c k . " . K a t i e t h e n p u t s t h e t o y c a r away a g a i n b u t t h i s t i m e s h e p u t s i t i n t h e r e d c o n t a i n e r . Sam d o e s n ' t s e e h e r p u t i t t h e r e . K a t i e l e a v e s t h e room a g a i n . B e f o r e K a t i e comes b a c k , Sam i s a b o u t t o come b a c k . He w a n t s t o p l a y w i t h t h e t o y c a r a g a i n . " 118 The e x p e r i m e n t e r t h e n a s k s t h e t e s t q u e s t i o n s a n d t h e c o n t r o l q u e s t i o n s as f o l l o w s : T e s t q u e s t i o n s "Does Sam know w h e r e t h e t o y c a r i s ? " "Where w i l l Sam l o o k f o r t h e c a r ? " C o n t r o l q u e s t i o n s "Where i s t h e t o y c a r now?" "Where d i d K a t i e a n d Sam f i r s t p u t t h e t o y c a r ? " " D i d Sam s e e K a t i e move t h e t o y c a r ? " 

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