A prime assumption of all simulation theories is that consciousness — the inner sense of awareness, like the sound of Gershwin or the smell of garlic — can be simulated; in other words, that a replication of the complete physical states of the brain will yield, ipso facto, the complete mental states of the mind. (This direct correspondence usually assumes, unknowingly, the veracity of what's known in philosophy of mind as "identity theory," one among many competing theories seeking to solve the intractable "mind-body problem".)Kuhn is raising the question here as to how, for example, the sensation of seeing blue or feeling pain could be simulated. Until there is a plausible physical explanation of consciousness, which there is not at this point, it seems very unlikely that conscious beings are nothing more than a simulation.
Such a brain-only mechanism to account for consciousness, required for whole-world simulations and promulgated by physicalists, is to me not obvious (Physicalism is the belief that everything in the universe is ultimately explicable in terms of the laws of physics. Physicalism is, for most purposes, synonomous with naturalism).
There's more of interest in the original article, including how physicist Paul Davies uses the simulation argument to refute the multiverse hypothesis. Kuhn closes his piece with this:
I find five premises to the simulation argument: (i) Other intelligent civilizations exist; (ii) their technologies grow exponentially; (iii) they do not all go extinct; (iv) there is no universal ban or barrier for running simulations; and (v) consciousness can be simulated.Personally, I find premise (i) problematic, premise (ii) possible, but questionable (it's just as likely that technological growth reaches a ceiling or collapses altogether), and premise (v) extremely doubtful.
If these five premises are true, I agree, humanity is likely living in a simulation. The logic seems sound, which means that if you don't accept (or don't want to accept) the conclusion, then you must reject at least one of the premises. Which to reject?
I also think it peculiar that people who scoff at the notion that an intelligent agent designed the universe when that agent is believed to be God, have no trouble believing that an intelligent agent designed the universe as long as that agent is not God.