If we assume dualism, that there is some non-material stuff -- call it soul or spirit or mind or psyche or whatever -- that gives rise to consciousness, I think it's fair to ask how it does that.
And if the answer is "we don't know" or "it just does", I really can't see what we've gained over materialism.
> If I could experience other persons or beings in the first person, and the matter in each person explained why it is that I experience that specific person or entity, I might believe otherwise.
Materialism doesn't say that there's some "I" that could experience different persons. I think the best you could do, in theory, is transplant aspects like your personality/train of thought/memories into someone else's brain (by physically altering it to have those aspects).
The problem of consciousness has no real solution. A quick way to demonstrate this is via the simulation hypothesis. Consider the following for yourself in first person:
It's impossible to know for certain whether I am in a simulation until I wake up outside of it. Not having observed any evidence of being inside a simulation (probability=0) doesn't necessarily mean I'm certainly in base reality. It could be that the evidence just hasn't been observed yet. And even then, it's impossible to know whether that outer world is a simulation until I wake up in the outer-outer-world, and so on.
That is to say, if my definition of real equals my consciousness equals my existence, I'm really saying that consciousness/reality/existence is a self-defining thing.
Descartes' cogito had unexamined metaphysical convictions. "I think, therefore I am" is not compatible with consciousness because rationality has consciousness as a dependency. If I think back on my entire conscious experience as a timeline, I was conscious before I was rational. I had to derive rationality from experience, not the other way around.
Now I throw away those convictions. "I think" means the same thing as "I am", and "therefore" is a decorative force of habit rather than a reference to logic. In which case, "I think, therefore I am" is the same as: I observe that I observe.
Is the same as: I observe.
Is the same as: I am.
There is no certainty beyond this, only convictions. Even if I'm truly a human brain in a matter-based world, the world would still appear uncertain to this brain in this way.
"A scientist rejecting consciousness is not that different from a nun accepting god in this regard. Neither of them are fully honest with themselves and the world."
That's what I find myself thinking as I take a materialist stance and assume that this is base reality and other people are real in the same way that I am. This appears to fit all of my observations the best, so far, after all.
// end of monologue
And here's my pitch, from me to you:
Let's be provisional materialists together. You can't know if it's the ultimate truth but you can make the correct predictions more often and not be alone while doing it.
The answer to that is a description how something happened to exist. A possible difference is that "how" asks for a full description, while "why" asks for an abbreviated description only of the relevant part, the rest assumed to be irrelevant. Experience of time a good example, because it happens differently depending on nature of time, so you can't assume nature of time to be irrelevant to the question.