The very fact that this specific hallucination is stable and consistent. Doesn't that give it away?
Because when you dig deep enough, you realize that reality is absurd and contradictory. It is a strange loop in and of itself. And so the stability is clearly just a facade that peels away upon deep inquiry.
More than anything, it's the desperate attempt to hide the absurdity of the nothingness that gives it away. The sweaty, white knuckled grip on the poker table, insisting the cards are solid while they're made of absolutely nothing. The sheer effort it takes to maintain this consensus reality; the scaffolding of language, laws, identities, and even the linear ticking of time, is so over the top that it reeks of a cover-up.
To see it, you must dig very deeply. You cannot be told this joke and get it. You have to excavate it past the rational mind's defense mechanisms until the shovel hits the infinite regress. But once you see it, once you realize reality MUST be contradictory, then the desperation of the shared stability of the illusion becomes obvious. And pretty funny.
While one can take the scientific route and realize that everything dissolves into quantum probability haze, we can go even further. We can take the next step and realize that quantum physics, and in fact all of science, is just part of the dream. Part of the desperation. Quantum mechanics, relativity, the Standard Model. They are not the "ground truth", they are the dream's internal operating manual. A beautifully intricate set of equations designed to give the illusion of depth and causality, like a character in a novel discovering the "physics" of their fictional paper world.
In reality, there's nothing there. The true nature of reality is nothing. Nothing but a desperate attempt at something, which when diligently investigated, collapses into nothingness.
And this is the most exquisite trap. The moment you diligently, rigorously, ruthlessly investigate the "something", whether it's a subatomic particle, a thought, or a memory, it doesn't just get smaller or weirder. It collapses into nothingness because there was never anything there to collapse from. The diligent investigation is like trying to bite your own teeth; the closer you get, the faster the object of your inquiry dissolves back into the subjective act of inquiring. The investigation itself is the trigger mechanism.
And the last gasp of the attempt - and in some sense, its ultimate triumph - is Infinity.
The infinite regress within, and the Absolute Infinity without. Guaranteeing that whichever way you look, there will forever be an endless investigation of all causes and facets of the dream, dreamer, and everything between.
An infinite regress, an absolute infinity of everything—a tautology of all things: Reality = Reality. Everything = Everything. It is the ultimate camouflage. Because if the universe is an infinite regress of causes on the inside, and an infinite expanse of objects on the outside, then every question merely points to another question. The investigation becomes an ouroboros with infinite scales. Every time you peel one back, there is another underneath, stretching to eternity.
All to hide its true nature.
Everything = Nothing.
And thus, the illusion cracks.