Knowledge And Its Use In A Program For Going From One Place To Another

The men ta l p rocesses i n v o l v e d in any human a c t i v i t i e s seem q u i t e complex . C o n s i d e r i n g as an example g o i n g f rom one p l a c e to a n o t h e r , t h i s paper a n a l y z e s men ta l b e h a v i o r i n terms o f t he r e p r e s e n t a t i o n and use of knowledge . We d e s c r i b e a n e t work memory to r e p r e s e n t knowledge, g i v e an accoun t o f t h e m e n t a l p r o c e s s e s , and p r e s e n t a program t h a t s i m u l a t e s our b e h a v i o r , f o r the p a r t i c u l a r p r o b l e m . I n t r o d u c t i o n A g r e a t p a r t o f ou r d a i l y a c t i v i t i e s seems t o b e r o u t i n e and t r i v i a l s c l e a n i n g , c o o k i n g , s h o p p i n g , e t c . a r e per fo rmed w i t h o u t demanding much o f our i n t e l l i g e n c e . Yet t he m e n t a l p rocesses ( b e h a v i o r ) i n v o l v e d i n these a c t i v i t i e s a r e f a r f rom b e i n g c l e a r a n d , o n the c o n t r a r y t o t h e i r s e e m i n g f u l t r i v i a l i t y , we r e a l i z e we a r e mak ing numerous d e c i s i o n s even when we go shopp ing f o r m i l k i wh ich marke t t o go to : by what means to go: wh i ch roads to t a k e t how much to buy: wh ich s e c t i o n o f t h e marke t to go to : where to pay: e t c . T h i s paper p r e s e n t s a n a n a l y s i s o f t he m e n t a l p rocesses i n such a c t i v i t i e s . I n p a r t i c u l a r , w e choose a n a c t i v i t y o f g o i n g f rom one p l a c e to a n o t h e r , make our a n a l y s i s i n terms o f t h e r e p r e s e n t a t i o n and use of knowledge , and s u b s e q u e n t l y d e s c r i b e a program to s i m u l a t e t he b e h a v i o r . R e p r e s e n t a t i o n o f Knowledge There a r e many s t u d i e s t h a t sugges t t h e k i n d s o f knowledge we possess , what t h e e lements o f knowledge a r e , how knowledge is o r g a n i z e d , and how i t may be u t i l i z e d t o p e r f o r m c e r t a i n t a s k s ( c f . 1 , 2 , 3 , 4 , 5) . An i n c r e a s i n g amount o f r e s e a r c h concerns v a r i o u s aspec t s o f our knowledge t o a t t a i n systems f o r b e t t e r u n d e r s t a n d i n g o f n a t u r a l l anguage , t o d e s i g n v e r s a t i l e w o r l d mode ls , o r t o c r e a t e a r o b o t t h a t r e a c t s t o i t s env i ronmen t c o m p r e h e n s i v e l y ( c f , 6 , 7 , 8 , 9 , 1 0 , 1 1 ) . What we know abou t geography , or a map l i k e t h a t i n F i g u r e 1 , may be e x p r e s s e d i n E n g l i s h sentences a s i E u c l i d Avenue meets Eas t 2k S t r e e t . P u b l i c L i b r a r y i s west o f A lpha U n i v . C i t y H a l l i s o n Lakes ide Avenue a t Eas t 9 S t r e e t . Bus T e r m i n a l is on Ches te r Avenue between Eas t 14 S t r e e t and Eas t 18 S t r e e t . When we c o n s i d e r these sen tences as t h e e x t e r n a l r e p r e s e n t a t i o n o f our knowledge on geography , one way to i n t e r n a l i z e i t i s t o a n a l y z e each sentence w i t h a f u n c t o r ( r e l a t i o n ) and i t s argument ( c o n c e p t s ) ( 1 2 , 1 3 ) . The knowledge a b o u t t h e map i n a n a p p l i c a t i o n o f t h i s t h e o r y may be c o n s i d e r e d as names of s t r e e t s and p l a c e s ( c o n c e p t s ) and r e l a t i o n s among them. The r e l a t i o n s e s s e n t i a l t o t he knowledge seem to be t h a t o f i n t e r s e c t i o n s ! d i r e c t i o n s , e t c . The i n t e r n a l i z e d knowledge may t h e n