Vimuktātman, an eleventh-or twelfth-century advaitin, was the author of a well-known work in Vedāntic philosophy called the I a Siddhi. The main contribution of this work lies in its subtle analysis of the problem of error or illusion (khyāti) as this is worked out in various non-Vedāntic and Vedāntic schools of thought. In order to illustrate this type of analysis in post-Śamkara Advaita we have selected a few short sections from an unpublished translation of the I a Siddhi by P. K. Sundaram of the Center for the Advanced Study of Philosophy, University of Madras.
III, 22. If apprehension of an object which is not in contact with the senses is accepted, then, the function of the senses being unnecessary, men of defective vision will always be omniscient. If illusion is due to the apprehension of similar objects, even then, there will be no illusion since it is cognized. If the knowledge of an object not in contact with the senses is accepted through the favor of defects, then, the knowledge of that not requiring the function of the senses, a man of defective vision should see everything always, since there is no distinction. If it be maintained that since similarity also is a defect, the apprehension of an object through defect requires the knowledge of a similar object, not when there is no apprehension at all; nor even when there is the apprehension of something else; and the correct knowledge is not from defect; error alone arises. Therefore, even a person of defective vision would not see everything always; to this,
We reply: when the object is apprehended, there cannot be any illusion, because of apprehension itself. And since, otherwise, there is undue extension.
Now: in your view also illusion is only in respect of what is apprehended. Indeed, when the substrate does not appear, there is no illusion.
(Reply): True, there is illusion only when the substrate appears. And not what is apprehended is the object of illusory knowledge; since it is accepted that illusion and its object are of the nature of māyā. And the substrate is not the object of illusion, since being sublated by silver, it loses its capacity of being the substrate. And, the Ātman, not cognized, is the substrate because of self-luminosity. Therefore, in my view, there is no illusion in respect of what is apprehended.
III, 23. If it is maintained that illusion results when the object is not cognized in all its aspects, then, let illusion be always, since no object is cognized in all its aspects. If it results when some special feature is not cognized, then, let illusion be always, since nobody realizes all the special features at any time.
If it is said: even when some aspect is cognized, there can be illusion as shell, etc., are not cognized in all their aspects, no; because of the contingence of illusion always. Indeed, by no knowledge, one is capable of cognizing an object in all its aspects. It is said (as a general rule): “An object is not cognized by any knowledge in all its aspects.” If it be said that even when it is cognized, illusion is through the non-apprehension of special features, even then, let illusion be always. Indeed, all special features are not possible to be cognized by any knowledge.
III, 24. And here, there is non-apprehension of any one of the specific quality. Is not the white color a speciality? The knowledge of the object (dravya) as white is not the knowledge of mere general features.
If it be said: all special features are not to be cognized; even when one specific quality is cognized there is no illusion, it is replied: When an object similar to the shell is perceived, the speciality, viz., white color, is cognized and hence it need not be an illusion. Indeed, the knowledge of similarities like white color is not the knowledge of mere general features, since a particular substance similar to the shell and associated with white color is perceived. Indeed, mere general feature is not similarity.
IV, 17. If it be asked: how the remembrance of an existent object be said to have an object, and how its remembrance can be without it, it is replied that it is so because of having that form. And the form also is possible because of latent impression even without the objectsense relationship.
If it be said: since the remembrance is observed even when the object is extinct, remembrance cannot be said to have an object; how can remembrance of that object arise without it?, (it is replied): because of being of that form. If it be asked: How can it have that form without sense-object contact, (it is replied), because of mere latent impression.
IV, 18. The object in the remembrance is only the form of knowledge and it is experienced by sāk in, witness-intelligence, and not by empirical knowledge. Since the witness is not perceptible like empirical knowledge (mental mode), there is no infinite regress, nor selfdependence.
If it be said: the extinct object, too, appears in the remembrance, (it is replied) that object is only a form of cognition born of the latent impression of the (earlier) cognition of the object, like the impression formed by a seal, and not an external object, since it is already extinct.
The same line of reasoning is to be adopted even in respect of what is not extinct, since remembrance is invalid. If it is the form of intellect, how can it be cognized by it? Not at all. It is to be apprehended only by the Witness. Sāk in or Witness being imperceptible, there is no infinite regress if it is apprehended by it as in the case of a mental mode, being perceptible by another mental mode.
The author gives another objection in respect of Ātmakhyāti.
IV, 19. For the Buddhist, there being no Witness, the mental mode is not witnessed by it; nor even by another mode because of the defects of infinite regress, etc., already mentioned. Nor even by itself.
IV, 20. If mental mode is not apprehended, there can be no apprehension of the object. If both are not apprehended, there can be no latent impression. Without it, there can be no form of silver for the cognition, because of momentariness.
IV, 21. There is no illusion, nor correct knowledge, and the whole world will thus become blind and dumb. Scripture, etc., will be baseless. Hence illusion is not Ātmakhyāti.