To answer Captain Boyle’s question (Juno and the Paycock) and say that the stars and all the furniture of the cosmos is an illusion, in the simplistic way that some proponents of advaitic vedanta do, would be wrong. Or should I say non-wrong because that 'all’ is not describable as real or unreal. Our attempt at closure fails because the criteria of closure are only operative, if at all, within the cosmos. For this reason the jnanis direct seekers into positive methods of inquiry:
For this reason, from the standpoint of the highest truth Advaitins should not be considered and spoken of as people who proclaim the falsity of the world. They should be considered, rather, as people who proclaim the sole existence and (undifferentiated) reality of the self. A false notion cannot be real while it lasts and then undergo obliteration at the time of correction. We find in the world that a rope, for example, will remain exactly what it is, even it be falsely imagined as a snake or the like. And in the same way, the Absolute remains what it is, even when it is falsely imagined as the world and soul and so forth. This is the finally accepted truth.(pg. 116 The Method of Vedanta by Sri SSS.)
The sentence beginning with A false notion seems to be backsliding into illusionism away from the positive inquiry of such as Ramana Maharshi with his Who Am I atma vichara or Nisargadatta’s reflection on I am. I rather take it to be a saving irony because analogies as such are still within the cosmos. There is no final answer in them.
Boyle: An’, as it blowed an’ blowed, I ofen looked up at the sky an’ assed meself the question — what is the stars, what is the stars?
Joxer: Ah, that’s the question, that’s the question — what is the stars?
Boyle: An’ then, I’d have another look, an’ I’d ass meself — what is the moon?
Joxer: Ah, that’s the question — what is the moon, what is the moon?
“Juno and the Paycock”, Seán O’Casey (1924)