ABSTRACT
To begin with we shall consider what, in English philosophical terminology, tarka is. On this point commentators differ. One school of interpretation renders tarka as reductio ad absurdum. Thus we find Y. V. Athalye writing, "Tarka - reductio ad absurdum — requires some explanation."4 Arthur B. Keith translates tarka as reductio ad absurdum, although he then notes that there are many varieties of tarka, only one of which is called reductio ad absurdum (the others seem to involve reductio reasoning only in a derivative sense.)5 In a book devoted entirely to a discussion of tarka Sitansusekhar Bagchi translates tarka as "reasoning," although in the title of the book he characterizes it as "inductive reasoning" and in the text he writes, "Here as elsewhere reasoning assumes the form of a reductio ad absurdum." 6 Another school of thought is represented by Satischandra Vidyabhusana, who characterizes tarka as confutation, but notes that it may also be rendered as "argumentation, reasoning, hypothetical reasoning, reductio ad absurdum, etc." 7 A third approach is represented by S. S. Barlingay's characterization of tarka as implication with a premise in contrapositive form.8 Finally, Karl H. Potter writes: "Tarka is sometimes rendered reductio ad absurdum, which is not altogether inaccurate, since tarka involves proposing a false hypothesis and then by showing it false proving the truth of its negation, or at any rate helping to prove the truth of its negation."9 Elsewhere in the same work Potter writes, "Tarka arguments are formally similar to 0 [an example of modus tollens reasoning], in that the first member is a counterfactual conditional proposition, the second denies the consequent of the conditional, and the conclusion is the denial of its antecedent."10 Potter seems to hold, then, that tarka should be rendered formally as a type of modus tollens reasoning, whereas many of the other commentators have in mind a conception of tarka as a variety of informal argument.
