What arguments did Abhinavagupta and dharmakirti make for the unreality of all external objects we know
An answer from Dignaga, Dharmakirti's teacher, and his pramana-samuccaya-vrtti, Dignaga's last and greatest work.
- Chapter 5 claims that words do not denote real things, and all a word means is that it is not (this "cow" is not a non-cow), and therefore a word cannot be used to cognize something.
- Perception (which is free from conceptual construction, verbal designation) has a particular for its object, and in the Buddhist scheme, that means consciousness of an organ in contact with an object. And perception is never mixed with inference (which may be valid, but always has the universal as its object, so its object does not exist), the only other type of cognition, because the latter is constructed by the mind through generalizing without regard for particulars.
- These two forms are identical to the cognition of an object, and self-awareness, respectively. Only these are necessary when we remember a cognition; and, given that things cease before the new cognition arises, momentariness, that is the only way to cognize something across moments.
Because only perception has the object as its object, there is nothing to know about it that cannot be revealed in perception, and this work, like his alambana-pariksha, argues that the object of cognition is nothing but its appearance in cognition: the object does not exist prior to cognition.
In the alambana-pariksha, dignaga proves that the object of cognition is nothing other than the appearance of the object in cognition itself. On the basis of this conclusion, he expounds the theory of self cognition in the pramanaamuccaya...
yad antar-janiya-rupam tu bahirvad avabhasate
Alas, I cannot translate it.
In effect, a refined form of parsimony, though he does of course argue with his detractors. In fact, cognition has no subject and object and all discourse is metaphorical, as all objects are just a momentary state in flux
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