ABSTRACT
T H E AM ALGAM ATION O F T H E TH EO RIES OF T H E A E T E T U S ,
PROTAGORAS, AND H E R A C L E IT U S (151-161)
A. The E le m e n ts of P r o t a g o r e a n i s m and H e r a c l e i t e a n i s m (151-155)
The m a in d ia lo g u e of the T h e a e t e t u s , a c o n v e r s a t io n b e tw e e n
S o c r a t e s , the g e o m e te r T h e o d o ru s , and his pupil T h e a e te tu s , b eg in s
w i th a b r i e f in t r o d u c to r y d i s c u s s io n (143d 1 -151 d 6) in w h ich S o c r a t e s
en g ag es T h e a e te tu s (146c) a s h is r e s p o n d e n t in an in v e s t ig a t io n of th e
question , W hat i s know ledge? At f i r s t T h e a e te tu s r e p l i e s by c i t in g
v a r io u s s c i e n c e s , a r t s , and c r a f t s a s " k n o w le d g e s 1' ( f c ln c T ^ ^ A i^ m u c h
a s u n d e r s i m i l a r c i r c u m s t a n c e s M eno th inks to say w h a t v i r t u e is by
e x p la in ing w hat the v i r t u e of a m a n , a w o m an , and so on, c o n s i s t in
(M eno 71 e ff. ). S o c r a t e s e x p la in s th a t he w a n ts to know w h a t k n o w ledge
i t s e l f is and not how m a n y v a r i e t i e s of i t t h e r e m a y be, and a f t e r a
d ig r e s s i o n show ing T h e a e t e tu s 1 g e o m e t r i c a l p r o w e s s and exp la in in g S o c
r a t e s 1 a v o c a t io n as in te l l e c tu a l m id w ife , the d i s c u s s io n tu r n s in e a r n e s t
to the a t t e m p t to de f in e know ledge . * t U N
O nce T h e a e te tu s u n d e r s ta n d s th a t in a sk in g otc Trorf
ov S o c r a t e s w is h e s to be g iven a g e n e r a l c h a r a c t e r i z a t i o n of
a l l th ings th a t a r e c a l le d , he i s p r e t t y e a s i ly p e r s u a d e d to
put a s id e h is in i t i a l d if f id en ce (148e) and p r o p o s e a d e f in i t io n of k n o w l
edge. The de f in i t io n , th a t know ledge is no th ing e l s e than p e r c e p t io n ,
i s no s o o n e r ann o u n ced th an S o c r a t e s e m b a r k s on a leng thy d e v e lo p m e n t
of the g rounds w h ich m ig h t le a d one to a c c e p t th is d o c t r in e . He f i r s t
a s s o c i a t e s T h e a e te tu s ' t h e s i s w ith the P r o t a g o r e a n d o c t r in e th a t m a n
is the m e a s u r e of a l l th ings and then c o n t r iv e s to m a k e P r o t a g o r a s 1
th e o ry i t s e l f a kind of e p is te m o lo g ic a l offshoot of a H e r a c le i t e a n th e o ry
of r e a l i ty . The v iew s of T h e a e te tu s , P r o t a g o r a s , and H e ra c le i tu s a r e
sa id , a s S o c r a te s c o n c lu d e s h is d ev e lo p m en t and exp o s i t io n of th e m , to
" c o m e to the s a m e th ing" ( l60d) , and T h e a e te tu s is r e p r e s e n t e d a s
holding th a t if H e r a c l e i t u s 1 and P r o t a g o r a s ' v iew s a r e c o r r e c t then p e r
cep t io n tu rn s out to be know ledge ( l6 0 e 1-2). ^ In the su b se q u e n t c r i t i
c i s m of the a m a lg a m a te d d o c t r in e th e s e d i f f e r e n t e le m e n ts a r e , in the
m a in , s e p a r a te ly in v e s t ig a te d and t e s te d . F i r s t P r o t a g o r e a n i s m
( I6 0 c -1 7 9 c ) and then H e r a c l e i t e a n i s m (181b-183c) a r e ex am in ed and
found to be f a l s e d o c t r in e s and th e r e f o r e not sa fe b a s e s on w h ich to
defend T h e a e t e tu s 1 de f in i t io n of know ledge a s p e rc e p t io n . It is only a t
th is po in t in the a r g u m e n t (184b-186e) th a t S o c r a te s and T h e a e te tu s
c o n fro n t d i r e c t ly the p ro p o s e d d e f in i t ion , w ithou t r e f e r e n c e e i th e r to
P r o t a g o r e a n o r to H e r a c le i t e a n d o c t r in e s ; and , in fac t , i t does not
tak e S o c ra te s v e ry long to show th a t p e rc e p t io n , c o r r e c t l y conce ived ,
is not only not id e n t ic a l w ith know ledge but n e v e r am o u n ts to know ledge
a t a l l .
