[whswhs]

Originally Posted by Ji ji

On the other hand, there are phenomena that we cannot simulate with a formal system. They are in two categories.
One is introspection or sentiency. As a qualitative phenomenon, it cannot be represented as formal system.
The second are undecidable propositions; we can manage them, but a formal system cannot.

The first is not a problem for the simulation. We never directly perceive the others’ experience of self; we just perceive their behaviours and we assume that they have self-awareness as we have*. In fact, if reality would be just a simulation feed to our brain, we could not tell the difference.

The second problem should be solved by the simulation use. Of course a computer simulating a mind would not have self-awareness or understanding of undecidable propositions, but it could behave like it had, and we couldn’t tell the diiference - as above.

It seems arbitrary for you to suppose that introspection necessarily gets credibility as a source of knowledge of our own consciousness/self-awareness, but extrospection doesn't get credit as a source of knowledge of an actually existing physical world. In fact, I think the other way around makes more sense:

If nothing exists, there can be no consciousness: a consciousness with nothing to be conscious of is a contradiction in terms. A consciousness conscious of nothing but itself is a contradiction in terms: before it could identify itself as consciousness, it had to be conscious of something. (Ayn Rand, Atlas Shrugged.)

And the reliance on formal systems is bound up with the idea that consciousness is primary. It goes back historically to David Hume's distinction between "relations of ideas" and "matters of fact," which was part of a philosophy in which there were no material objects, no cause and effect, no continuing self, no reliable memory, no other minds; there was only an ongoing stream of sensations, which constituted both all that we could know of physical reality and all that we could know of our own minds. For Hume, "relations of ideas" were purely formal. For existence-first or "outside-in" philosophers like Aristotle, logic wasn't just "relations of ideas": it was a statement of how things were in reality, to which human thought had to conform if it was to be about reality.

I think that consciousness is consciousness OF something. And I also think that consciousness is a process taking place in a physical being, and manifested in the activity of such a being—in particular, in its orientation to the things it's conscious OF.

When somebody's lying on the ground after a car crash, one of the things the paramedics check is whether the person is conscious. And they don't do this by engaging in arcane philosophical discussions, or by applying some sort of advanced scientific instruments; they attempt to get the person's attention, talk to them, see if they can track what's going on around them, and so on. They check whether they're engaged with the external world. So when philosophers talk about consciousness as some sort of mysterious inner state, they're talking about something entirely different from the ordinary meaning of "consciousness"; in fact, I think, about a philosophical chimera.

I would add that discussion of whether we "directly perceive" others' consciousness seems to involve another double standard. What does it mean to "directly perceive" something? I can see my checkbook on the desk in front of me. But that isn't some sort of causeless, meansless event; I perceive it because it reflects light, because light stimulates the cells of my retinae, because they fire nerve impulses, and so on. That doesn't seem "direct." On the other hand, saying that I don't directly perceive the checkbook doesn't entail that there is something else that I DO directly perceive, such as an image of a checkbook in some hidden realm of consciousness (what Dennett calls the "Cartesian theater"), or that I logically infer the physical checkbook from the inner representation of the checkbook; it entails that this idea of "direct perception" doesn't mean anything. I perceive that the checkbook is on my desk, and I perceive (for example) that my cat is awake and has heard something, and both of those are results of my brain putting together information from my senses—and not doing so through a process of logical inference. Perception is a physical process, just as much as flight is, or burning; a computer model of perception no more results in anything perceiving the physical world than a computer model of fire results in flame, smoke, or ash or consumes fuel.