I have a problem with
"reality is an illusion". I know it's a statement/concept that has a power & a truth to many people. But...
The way I see it, calling something an illusion doesn't really say anything about the thing you're describing. You call something an illusion because
your initial interpretation was wrong/inadequate, and you want to blame the thing. In the case of a magic show, you know that it's because a skilled performer anticipates and exploits the limits and quirks of your attention & perception. So of course you are quite right to blame the thing. But that situation, where you think along the lines of
"a grand show is being put on, specifically for my benefit, designed and tuned to distract and mislead me"... that really seems like the wrong model to take with you when you go on to consider other, bigger kinds of illusion. It's too simplistic, self-centered. And I feel kinda distrustful of anything that encourages me to think that way.
Two things you might learn about the nature of reality during childhood. One: there's no Santa Claus (apologies for Christianish-culture-centric perspective here). Two: everything is made up of
atoms - even the densest, heaviest object you can think of ain't truly, continuously "solid" in that way you would (likely) have otherwise always assumed. Of those two revelations, the one that people tend to reach for as a shorthand for "childhood reality betrayal" is the Santa Claus one. Like the magic show, it's all about being deliberately, continuously lied to. Getting tricked by a theatrical performance. (The Matrix movie with its famous character Red Pill is another example of Santa Claus/magic show-style reality betrayal.)
Do you remember the moment when you first understood that everything is made of atoms? Maybe you never really did. I mean, unless you actually work in specific scientific fields, you have no reason in daily life to ever face the fact of atomic reality, to take a decision that would mark you out as either an atom-believer or an atom-denier.
Suppose in reality there’s a resource, like water, and you can quantify how much of it there is in an objective order—very little water, medium amount of water, a lot of water. Now suppose your fitness function is linear, so a little water gives you a little fitness, medium water gives you medium fitness, and lots of water gives you lots of fitness—in that case, the organism that sees the truth about the water in the world can win, but only because the fitness function happens to align with the true structure in reality. Generically, in the real world, that will never be the case. Something much more natural is a bell curve—say, too little water you die of thirst, but too much water you drown, and only somewhere in between is good for survival. Now the fitness function doesn’t match the structure in the real world. And that’s enough to send truth to extinction. For example, an organism tuned to fitness might see small and large quantities of some resource as, say, red, to indicate low fitness, whereas they might see intermediate quantities as green, to indicate high fitness. Its perceptions will be tuned to fitness, but not to truth. It won’t see any distinction between small and large—it only sees red—even though such a distinction exists in reality.
Is that really the best example? How was there ever any guarantee that this fitness function was about measuring the amount of water, with low/red meaning "less water" and high/green meaning "more water"? It's measuring something else, something a bit more complex. So what?
Also, wouldn't "not enough water" and "too much water" require different responses anyway? Like if there's no water, you can head in pretty much any direction you like in the search for more water. But if there's too much water, you are likely to really have to turn around and go back the way you came to avoid drowning. So whatever that secondary thing is that lets you differentiate your response, combined with the red/green system,
that's what gives you your interpretation of too much/not enough water.