Modern Vedantism
... some modern Vedantists ... claim that the two states in question [the waking and the dreaming egos] are quite unrelated, that the dreaming ego is not in any way the same as the waking one, that the two states are closed systems and that it is incorrect to take the waking ego as the point of reference for the dreaming consciousness;(1) and that consequently, the latter is in no way inferior to the former nor less real(2).
(1) Like Kant, Siddheswarananda, for instance, seems to think that his own experiences limit those of others.
(2) Some have even gone as far as to claim that dreaming is superior to the waking state since it comprises possibilities which are excluded by the physical world, as though these possibilities were anything but purely passive and as though the objective and determinant reality of the waking state did not compensate infinitely for the dream possibility of rising into the air; or again, as if one could not just as well dream of being deprived of movement.
This extravagant and pseudo-metaphysical opinion is contradicted, in the first place, by the fact that, on awakening, we remember our own dream and not someone else's; secondly, by the fact that the inconsistent and fluid character of dreams, on the one hand, and on the other, their reference to our subjectives experiences, prove their subjectivity, their passivity and their contingency; and, thirdly, by the fact that, while dreaming, we can perfectly well be aware that we are dreaming and that it is we -- and not someone else -- who are dreaming. The proof of this is that it may happen that we awaken of our own free will when the development of the dream takes a disturbing turn. On the other hand, no one would think of making an effort to emerge from the waking state -- however disagreeable the situation -- in the hope of awakening into some paradisial state with the conviction that one had emerged from an accident of one's own imagination, whereas in reality the terrestrial world would remain what it is. Certainly the universe is, in a sense, an illusion in relation to the Principle, but the objective world is not an illusion in relation to a particular subjectivity on the plane of relativity. (Esoterism as Principle and as Way, p.215-216).
If the opinion which unconditionally confuses the states of waking and of dreaming were well founded and if these two states were equivalent precisely on the plane of relativity -- whilst in reality they are so only in the sight of the Absolute -- it would ne indifferent whether a man was a sage dreaming he was a fool, or a fool dreaming he was a sage. (Gnosis, Divine Wisdom, p. 71).
The de facto ambiguity of this question is in part explained by the fact that the Hindus, who knew what was implied in such matters, have never in their expositions, which are deliberately elliptical and centered on the essential, gone out of their way to offer precisions which seemed to them pointless; but one must not take dialectical syntheses fro mere simplifications and draw absurd conclusions from the doctrine of illusion, an error of which the ancient followers of Vedanta were clearly not guilty, or they would have been common solipsists. Schopenhauer was wrong in thinking that solipsism is logically irrefutable, but right in declaring solipsists to be ripe for the lunatic asylum. (Gnosis, Divine Wisdom, p. 71).
A world is ... a collective and nevertheless homogeneous "dream" whose constitutive elements are obviously compossibles. Subjectivists falsely inspired by Hindu doctrine readily forget that the world is in nowise the illusion of a single individual; in reality it is a collective illusion within another collective illusion, that of the whole cosmos. (The Eye of the Heart, p. 5, note 6).
Pseudo-Vedantist 'subjectivism'-- which in reality is solipsism -- is incapable of taking stock of the objective homogeneity of the cosmic environment. (Spiritual Perspectives and Human Facts, p. 114).
(1) Such as Mormonism, Bahaism, the Ahmadism of Kadyan, and all the "new religions" and other pseudo-spiritualities which proliferate in today's world.