[naasking]

> But can it? To say something is an illusion is to say that is really an experience of something else.

Your definition for "illusion" begs the question by simply assuming a subject is needed, ie. an "I" must experience an illusion. Rather, an illusion is simply describing the relation between perception and truth. If a perception, taken at face value, entails a false conclusion, then it's an illusion.

Even the basic dictionary definitions of illusion make no reference to a subject. They're all of the form of "a false idea or belief", or "a deceptive appearance or impression". Beliefs and appearances are attributes we can ascribe to mechanistic systems too, like computers, which can have sensors plugged into Bayesian inference engines that can infer false "beliefs".

So requiring a subject is a property that you have imposed on the meaning of illusion, it's not intrinsic to it.

[Qcombinator]

I made no reference to a subject either. For "my" experiences to be not really "anybody's" experiences is a somewhat separate problem. As is a belief that I don't really have any beliefs, and so on. Any attempt to eliminate qualia or self or intentionality, etc. as being fundamental realities runs into the problem that all these things are more fundamental to my understanding than any proposed alternative.

[naasking]

Your definition of illusion still begs the question, either by assuming a subject or assuming a reduction to further experience is needed. Like I said, illusion only requires that perception differ from truth.

> Any attempt to eliminate qualia or self or intentionality, etc. as being fundamental realities runs into the problem that all these things are more fundamental to my understanding than any proposed alternative.

1. Perception is fundamental to understanding. Whether experience is fundamental is very questionable.

2. Being fundamental doesn't entail something is irreducible. Being in a car is fundamental to driving on a road, that doesn't entail cars are irreducible.