because we’re still living in this physical world, so we have the physical substrate for the abstract concepts. But in all possible worlds there certainly will be some where those abstract concepts are all there. Then you could imagine an afterlife that’s very much like the spiritual afterlife that a lot of religions imagine–where there is no physics. There’s only psychology.
David: It’s all mind.
Hans: Right. I think all of these concepts here need further work. But note, all of this allows artificial intelligence. The robot minds are just as real as ours. None of this contradicts it. So those people who try to use this kind of thinking to rule out robots don’t have a leg to stand on.
David: Do you see any evidence for teleology in evolution?
Hans: No, not per say. On the other hand, in the scenario of all possible worlds, the one where the physical world is the only thing there is, is an infinitesimal part. So we could be in a video game. We could be in somebody’s imagination. In fact, there’s reason to think that actually our existence is entirely Platonic, and that we are just one universe out of a very high order of infinity of them. And the only reason we see this universe is because it provides simplest explanation of us. There’s a probability argument that the universe which provides the simplest explanation of us is the one that we’re most likely perceive, although we probably exist in a way that–from our personal perspective–we could not distinguish in many different universes.
David: What is your perspective on the concept of God?
Hans: I don’t even know what that means. Certainly in some of the video game universes there would things like gods, who are playing the game. (laughter) But no, I’m rather unimpressed with the traditional sort of tribal gods. (laughter)
David: Do you think that the human species will survive the next hundred years, or do you think that we’re in danger of extinction?
Hans: I think the whole concept of survival is not very well defined. I think we’re on a road where we’’ll probably be transforming into something that will survive in the universe, as we currently conceive it. But I think we’re going to grow into a form where our conception of what the universe is is going to change radically, so that the concept we currently have of survival is pretty parochial.
David: How do you envision the future evolution of the human race?
Hans: I think we will be building successors that are vastly more capable than we are. Blind biological evolution kind of bootstrapped itself up to the point where we can now take the future into our own hands, however imperfectly at this stage, and sort of bootstrap ourselves further into a form where, naively speaking, we’re smarter. Our descendants, anyway, will be much smarter than we are, and able to engineer their own further development even better. That’s a positive feedback process that rapidly goes to a stage that we can’t even imagine at this point.
David: How long do you think it will be before computers exceed human intelligence?
Hans: I’ve been redoing and redoing that calculation since the Seventies, and for the last twenty years the answer I’ve been coming up with is about the same–which is before 2050. At various times I throw in the numbers–the latest projections of computer power, and the latest estimate of how much computer power is needed to do various nervous system functions–and what I get is somewhere from 2020 to 2050.
David: Could you talk a