Modern arguments for machines having consciousness can, I suggest, be paraphrased as follows:
- (Suppressed premiss) We do not know what consciousness is or how it works
- We have, on the other hand, lots of ideas about how electro-mechanical systems work
- Let us believe that consciousness is an electro-mechanical system, because if it were we would be able to understand it.
But incidentally, (3) also happens to imply
- Machines can be conscious.
I have no disagree with the observations 1 & 2, but 3 has nothing to motivate it other than the firm conviction that, whatever our current state of knowledge happens to be, it must be good enough to understand anything we really want to understand.
A better move than step 3 would be simply to repeat observation 1 and say we don't know what it is or how it works. This rather undercuts step 4; perhaps step 4 is best left behind in the science fiction stories it came from.