X-Message-Number: 3782 From: (Thomas Donaldson) Subject: SCI.CRYONICS Re: brain as net Date: Thu, 2 Feb 1995 11:59:51 -0800 (PST) Hi! A comment about Ettinger's ideas re the possibility of reproducing a brain in a computer: One fact about our nervous systems which may be growing more and more clear is that the number of our synapses increases when we learn. There is another article suggesting this in the latest PERIASTRON. In terms of simulating or emulating a brain on a computer, this would cause a problem. Our computer-brain would need to have some way to increase the number of its connections. (I agree that we are best imitated by neural nets, but there are a variety of DIFFERENT neural nets, and the exact imitation of even a small brain hasn't yet been achieved). The ability to grow new connections is clearly something hard to simulate with one of our present computers. If we insist that it not be biological in the sense of using present biological methods for growing new connections, I'd say that's probably something that will be possible, but even so, this may give a real example of something in our brains which constrains the materials of which they can be made. (And it's much more to the point than suggestions about tissue paper, too!). Of course, we don't actually KNOW this yet. That merely emphasizes Bob's point about how we basically don't know enough to say, as yet. No, I don't agree with Bob about everything. I have strong doubts that we can validly derive rational values from statements about what is. But that's a whole different discussion. I would be happy to review Bob's book, whenever it comes out and whoever publishes it, and give my own ideas on that issue. I will also say, though, that it may be possible to derive much more about values if we start with some central values which are accepted as given: as most cryonicists, we want to live, for instance. That may have many consequences, but I'll leave that to another time. Long long life, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=3782