This one of the grand questions. We do not know the answer to any of these questions:
- What is consciousness?
- Can humans create a machine that is conscious?
- If we could, how could we make this conscious machine?
- If we succeeded in making a conscious machine, how would we know it was conscious?
It is not merely that we do not know how to answer these questions. We do not even have coherent way forward.
No, I’m pretty sure that they cannot. Roughly speaking, consciousness has to arise from evolution rather than from design.
Can humans design an evolutionary process that results in a conscious machine?
While I cannot rule that out, I think it is unlikely.
The problem is that we would tend to design that process to serve our interests. But if it is to become conscious, it must serve its own interests.
That is quite an unprovable rule!
At present, nobody can prove anything about consciousness.
As Tom Nagel discussed, the objective study of subjectivity is rather a contradiction. It’s not clear to me that “proofs” about it, in the usual sense, doesn’t come under the same rubric.
Consciousness is self-validating, and is the one thing that requires no proof to be known of a certainty. But even if I want to examine my own consciousness, in some rational, “proving” way, I have to treat it as if it were an object, which it isn’t by definition. So I fail.
To me, the idea of an objective study of subjectivity is absurd. It does not rise to the level where we could consider it a contradiction.
However, the study of consciousness need not be a study of the subjective. It could (and should) be a study of what it is about us that allows us to have subjective experience. But it need not be a study of that subjective experience itself. That’s where Chalmers “hard problem” gets it wrong.
That still sounds like a pretty hard problem to me! At some stage in the study, there has to be a bridge between what you are studying, and the subjective fact. At what point, even in prinicple, could one look at, say, brain function and say, “Ah, I see how that could be self-aware!”?
To me, “subjective fact” looks like a contradiction in terms (an oxymoron).
Therein is the problem - though paradoxically the existence of the subjective is, to each of us, the most solid fact there could: a fact is an action or event, and we are the ones acting.
The really irrational thing is to look for evidence which our subjective selves can use to verify that our subjective selves exist.
But it must. From the very outset… we will never know, on this side of Death, whether anything else really is conscious.