Adi Shankara's doctrine of Maya is very widely known specially among the Vedantins; according to which all the dualities are perceived by self owing to ignorance(avidya) and that self is one without a second.
My question is regarding Shankara's commentary on Bhagvad Gita 13th chapter verse 2. i'm reading translation of Alladi Mahadev Shastry. (check page 334)
Here Purvapaksh raises a question regarding relation of self and avidya. In reply this is what Shankara says:
It is not indeed possible for you to perceive your Self as related to avidya, at the same moment (that your Self cognises avidya); for, the cogniser (Self) acts at the moment as the percipient of avidya. Neither can there be a (separate) .cogniser of the relation between the cogniser (the Self) and avidya, nor a separate cognition of, that (relation) ; for then you would commit the fallacy of infinite regress (anavastha). _ If the relation between the cogniser (the Self) and the cognised could be cognised, another cogniser should be supposed to exist; then another cogniser of that cogniser ; ,then another of that again; and so on; and thus the series would necessarily be endless.
So here my question is regarding part in bold. Why Shankara thinks that Percipient cannot perceive a relation between himself and the perceived?
Ex say. I cognize my mother and at the same time cognize the relation between us as that of son-mother.
But from my understanding of Shankara's comment it appears to me that Adi Shankara doesn't think this is possible. He thinks that a relation of son-mother can only be perceived by some third person(other then mother and son).
So why does Shankaracharya think that such a case is impossibility?