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THEORY OF KNOWLEDGE
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is cognised not by itself but by another cognition, then what should take place, though it never does take place, is that the cognition of the first letter of the word is followed by the cognition of this cognition; then follows the cognition of the second letter to be followed by the cognition of this cognition, and so on and so forth22.
Besides, another point has been made. Since it is always possible to have memory of a past cognition and since no such memory can take place unless this past cognition was cognised at the time it took place, this past cognition - unless selfcognised - must have been immediately followed by a cognition of itself; and since the consideration that applies to the original cognition also applies to the cognition of this cognition, this second cognition must have been immediately followed by a cognition of itself, and so on and so forth. The result would be, so thinks Dharmakirti, that on the rival view one should spend one's whole life-time cognising an object, then cognising this cognition, then cognising this new cognition, and so on and so forth.23
One aspect of Dharmakīrti's discussion on the nature of cognition as such deserves separate consideration. For in the relevant portion of the Pramanavārttika, Pratyaksapariccheda (vv. 300-541), he has come out with a detailed and repeated defence of idealism24. The venture is rather intriguing because it puts in serious jeopardy the findings in Dharmakīrti's own earlier treatment of logical problems. Thus the most conspicuous and crucial feature of Dharmakīrti's logic is the sharp distinction drawn between sensory experience and thought, a distinction which crucially, hinges on a clear-cut admission of the reality of physical objects; on the other hand, the central aim of idealism is to deny that there exist any real physical objects. Little wonder that it is the same language Dharmakirti uses both when speaking about thought in the context of logical problems and when speaking of sensory experience in the context of his defence of idealismas. For example, he earlier tells us that the sensory experience of fire is different from the thought of fire because the former takes place when fire as a physical object acts on an appropriate sense-organ while the latter takes place when some association of ideas reminds one of fire; but later he argues that the sensory experience of fire too takes place not because of the presence of fire as a physical object but because of some sort of association of ideas. Likewise, Dharmakirti earlier makes a serious attempt to distinguish a genuine sensory experience
