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TEST OF TRUTH AND ERROR
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there is no contradiction for the present or that there cannot be a contradiction at any time. But to know that there is non-contradiction for the present is not to know that the knowledge must be valid. For what is not now contradicted may be and often is contradicted in the future. That there cannot be a contradiction at any time is what we can never know unless we become omniscient Absolute noncontradiction is therefore an impracticable test of truth. Nor? again can the validity of knowledge be known from its/ coherence with some other knowledge (samvāda). For this will lead to infinite regress. How can we know tbat there is real coberence between two cases of knowledge? How again do we know that the second knowledge, with which the first coberes and by which it is tested, is itself valid ? To prove the validity of the second we must show its coherence with a third and so on ad infinitum Or, if we stop anywhere and say that the last knowledge or the system of knowledge as a whole has self-evident validity, there is no reason why the first knowledge cannot be said to bave the same selfevident truth It cannot also be said that the coherence of knowledge consists in the volitional experience of expected results. The mere experience of desired objects is no evidence of the validity of knowledge. In dream we have vivid experiences of many desired things. This however does not make dream a valid knowledge at all. Thus we see that there cannot be any extraneous test of the validity of knowledge, like correspondence, coherence, non-contradiction or pragmatic utility. Hence knowledge_must_testor certify its own truth, i.e. the validity of knowledge is self-evident.
As to invalidity or falsity, the Mimāmsakas and the Vedāntists hold that it is extrinsic to knowledge. Wbile truth is organic to knowledge, falsity is accidental
I VP. & 8D., sbad , NM , pp. 162-65.