। ॥ ६०२ ॥
In plain words
By what means could this Self be perceived? For the Self is itself the ultimate perceiver. Because there is no other instrument of awareness apart from it, the Self is never caught as a mere object of perception.
Close to the Sanskrit
By whom indeed might this be perceived? The perceiver is self-luminous. Therefore, because of the absence of any other perception, this Self is not perceived as an object.