Illusion is just what we call a model that we've determined isn't an accurate reflection of reality. It's curious that you're asking your questions about "illu

Illusion is just what we call a model that we've determined isn't an accurate reflection of reality. It's curious that you're asking your questions about "illusions" in particular -- you should be asking them about "mental models" in general. Your idea of a lightbulb doesn't exist outside your brain any more than your idea of redness or free will does. Your brain is playing a trick on you and correlating your idea of a lightbulb and lightbulbs in the real world. That's a useful trick, of course, because otherwise we wouldn't be able to interact with the world, because obviously our brains can't shuffle real lightbulbs around inside itself like it shuffles idea-of-lightbulbs around. But it leads to confusion when dealing with mental models that may be useful but don't correspond to anything in reality.