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48
NYAYA THEORY OF KNOWLEDGE
mark of the absence of smoke. Hence if it be said that there is absence of fire in the object, we cannot resist the conclusion that there is absence of smoke in it, 1.e. it 18 smokeless. Such a conclusion, however, is contradicted by direct observation. Hence it is that tarka has been defined by the modern Naiyāyikas as the process of deducing from a mark that of which it is a mark, but is false (vyāpyāngikārena anistavyāpahaprasañanai ūpah) ?
When the proposition establisherl by any method of knowledge (pamāna) is doubted or disputed, we should have recourse to tai ka to lay the doubt or end the dispute. In tarka we take the contradictory of the proposition in the form of a hypothesis and readily see how that hypothesis leads to a contradiction Hence tarka se ves as the limit to doubt (sanlāraih) Since, however, the invalidity of a position is not a ground of the validity of its opposite, tarka is an aid or auxiliary (sahakārī) to pramāna, but not pramāna by itself. Thus when on seeing a talile we say:
there is no book on the table, we have a judgment of perception expressed in a proposition If anyone doubts the truth of this proposition we may effectively dispel it by an argument like this “If there were any book on the table, it would have been perceived like the table; but it is not so perceived; therefore it does not exist.' But to argue in this way is not to know the non-existence of a book on the table. The knowledge of the book's non-existence is a matter of perception according to the Naiyāyikas. Similarly, to argue that if the object be fireless it must be smokeless,' is not to know that it is fiery. The knowledge that the smoky object is fiery is acquired by means of inference from smoke as a mark of fire. The hypothetical argument only confirms this inference. Hence tarka does not ori. ginate true knowledge, i.e. is not a pramāņa, although it
1 TB., p. 82.
