Vedanta says that what we truly are is Existence-Consciousness-Infinity (= Brahman).
The universe is an illusory appearance on/of this substratum of Consciousness. It is not real.
The jiva (= mind = I-thought = ego) is part of this illusory appearance. It is a result of the erroneous super-imposition of an I-thought arising between the insentient appearance and Consciousness. Thereafter desire, fear and suffering, like and dislike ensues.
Dennis asserts that jnana is equivalent to having the intellectual knowledge, which must be a thought, that ‘I am Brahman’. But that is still a thought, part of the illusory appearance.
When Vedanta says a jnani becomes Brahman, it may be countered that we are always Brahman. But the frequency of use of this terminology implies something more subtle, beyond just a knowledge-thought arising in the mind.
We are told by Vedanta that Brahman cannot be known; that the only ultimate pointer is neti, neti: the negation of all the illusory appearance; and what remains, what cannot be negated, is That.
Ramanamaharishi provides a further clue. Whenever desire or fear or suffering arises, try to introspect, to turn within, to grab hold of the ‘I’ that is suffering. The process of doing so turns the ‘mind’ away from its desire/fear/suffering thoughts. He goes on to say in Nan Yar:
Only by the investigation who am I will the mind subside [become still]; the thought who am I, having destroyed all other thoughts will itself in the end be destroyed.
This final link is affirmed unequivocally by Brhad Up, Sankara and Gaudapada.
Brhad Up 2.4.12: After attaining this oneness, it has no more particular consciousness.
Sankara’s bhasya: When that individual existence of the self which is superimposed by ignorance is destroyed by knowledge, the particular consciousness is destroyed, being deprived of its cause.
3.31: All this that there is is perceived by the mind (and therefore all this is but the mind); for when the mind ceases to be mind, duality is no longer perceived.
3.38: There can be no acceptance or rejection where all mentation stops. Then knowledge is established in the Self and is unborn, and it becomes homogeneous.
3.46: When the mind does not become lost nor is scattered, when it is motionless and does not appear in the form of objects, then it becomes Brahman.
In conclusion then, to know Brahman is to be Brahman, and to be Brahman means no further arising of the ‘I’-thought; a motionless mind.
Ramanamaharishi in his Guru Vachaka Kovai issues this warning:
897: O my mind who is suffering by thinking ‘I am jiva’, you will again be deceived if you think ‘I am Brahman’. Because in the supreme state nothing exists as ‘I’ but only the one Self.
Liberation from the ‘I’ is ultimately a ‘personal’ affair. It would seem better to assume a position that may be a false negative rather than one that could involve the self-deception of a false positive.