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TEST OF TRUTH AND ERROR
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On the other hand, if we accept the Prābhākara view that knowledge is self-manifest and guarantees its own truth without reference to anything else, we do not see how there can be doubt and suspicion, or how there can be any failure of practical activity. Since valıdıty is inherent and self-evident in knowledge, every knowledge must carry in it an assurance of its truth and we should have no doubt. Similarly, every knowledge being true and known to be true by itself, there cannot be any disappointment in practical life. But doubts and disappointments are very common experiences of life. If it be said that doubt arises out of contradiction between two cognitions and is resolved by a third cognition, we are forced to give up the idea of self-evident validity. The third cognition may not constitute the validity of the first by reason of its coberence with it, but it at least conditions our knowledge of its validity So the validity of one knowledge is known by another knowledge. In fact knowledge only reveals its object. To know that it is valıd, 1.c. it truly reveals the object, we must have some extraneous test like coherence with volitional experience or some accredited past knowledge. Hence the validity of knowledge must be known from external conditions.
It will appear from the above discussion that the Naiyāyikas are not prepared to accept the theory of intrinsic validity. That truth is intrinsic to and self-evident in all knowledge is not admitted by them. But that the truth of some cases of knowledge is self-evident is admitted by some Naiyāyikas. There is on this point a difference of opinion between the ancient and the modern exponents of the Nyāya. The older Naiyāyikas insist that a proof of the validity of any knowledge requires the exclusion of other suggested possibilities contrary to it. Hence we find that
1 Ibid.
