P.183

　　   The history of Indian logic is usually  divided into
　　   three  periods,  Old  Nyaaya  (circa  250  B.C.  ) ,
　　   Buddhist  logic (sixth century A.D.) and New Nyaaya.
　　   The　　 Buddhist　　 logic　　 text,　　 Nyaayaprave`sa
　　   (Introduction   to  Logical   Methods) ,  had  great
　　   influence  upon Indian and Chinese Buddhism and also
　　   among   the   Jains.   As   a   pivotal   work,  the
　　   Nyaayaprave`sa  has received critical attention from
　　   historians  of religion, philologists, philosophers,
　　   and logicians.  As with all advances in scholarship,
　　   there is controversy over interpretation, but in the
　　   case of Buddhist logic, the controversy  cuts to the
　　   very heart of the issue of whether Buddhist logic is
　　   in any recognizable  contemporary  sense  a "logic."
　　   The received  view holds  that Buddhist  logic bears
　　   very close  similarities  to syllogistic  forms  and
　　   that it can be represented  and analyzed by standard
　　   deductive   techniques.(1)  A  much  different   and
　　   opposing  view has been argued by Professor  Douglas
　　   Daye in a series of papers. Daye maintains that "...
　　   the descriptive  utility of mathematical  logic with
　　   early  Nyaaya  texts has simply  been overrated";(2)
　　   that although  the Nyaaya texts contain  metalogical
　　   rules　　 for   evaluating　　 the   "legitimacy　　 or
　　   illegitimacy" of arguments, the distinction between
　　   validity  and  invalidity  does  not  apply;(3) that
　　   Nyaaya  models are not inferences  but  "formalistic
　　   explanations";  and that "...  Buddhist logic is not
　　   deductive, nor can it be formally valid nor is it an
　　   inference."(4)

　　　　  The  cumulative  effect  of these  claims  is to
　　   assert that Buddhist  logic is not a "logic" at all,
　　   at least  not in any sense  which  is recognized  by
　　   Western　　 philosophers.　　 There   is   a   radical
　　   incompatibility  between the Nyaaya methods of logic
　　   and  those  of  the  Prior  Analytics  or  Principia
　　   Mathematica.  Of course, there  will be differences,
　　   possibly  very  great  differences, between  any two
　　   traditions  so  diverse  as  fourth  century  (B.C.)
　　   Greece and sixth century (A.D.) India, but are we to
　　   go so far as to say that the Nyaaya does not contain
　　   inferences? The radical incompatibility thesis is, I
　　   maintain, a mistake; moreover, it is a mistake which