X-Message-Number: 25114 Date: Sat, 20 Nov 2004 07:57:07 -0500 From: Thomas Donaldson <> Subject: CryoNet #25083 - #25103 The 18 November (Thursday) Cryonet had lots of discussion both of RBR's ideas and that of others. Here are some comments + references bearing on each of them (hopefully this message won't be too long). For RBR: Whether or not our QE (qualia experiencer) can be truly duplicated looks like a central element in your ideas. However there's a problem with it to which I'd want an answer: suppose you have been anesthetized (if I understand history, anesthesia actually raised some of the same problems when it was first used). In the first case, we have some very fast way of replacing all the molecules in your brain with copies of them, including their relations with the other molecules in your brain. In the second case, we record an exact copy of you and your brain, destroy the original, and replace it with an exact copy taken from our record. We then wake up the person from anesthesia. If I understand you, the first case will continue the original QE, while the second does not. Please explain just why this is so. I will of course not accept at all the mere statement that it's so. For Francois: I am most certainly aware of work with (computer) neural nets. I was (and in a sense still am) a mathematician by vocation, and got into the computer industry to work with parallel computers. The main problem with a brain running on a single computer is that The main problems with brains running on single computers are: 1.Brains are far larger than any neural net we now have or envision. 2.Each of our neurons acts as its own primitive computer, with all of them running in parallel. No single computer could emulate such parallelism. Example (theoretical only): suppose we have 2 neurons running together on related problems, and each requires input from the other at one point of the computation. Parallel neurons can send input to one another while at the same time receiving input from the other. 3.VERY IMPORTANT: our brain not only makes new connections between its neurons as part of (and perhaps even the whole of) forming a new memory, it makes new neurons too. Along the way, of course, it also sometimes destroys neurons. In one sense this even makes brains closer to Turing machines than any computer we've yet built. (Recall that Turing machines write and read on an infinite tape). Neurons aren't limited to a fixed set of connections, nor are our brains limited to a fixed number or set of neurons. I would not deny that these features could be imitated on a small scale with suitable neural net computers. The serious problems come when you propose to do the same with human brains (or even ape or monkey or porpoise brains). And yes, there are certainly other ways to wire together our neurons, but no matter how you propose to do so even with mammalian brains you'll have a problem. The number of neurons becomes large enough that a simple scheme for just a few neurons becomes unwieldy when you try to implement it for millions of neurons. For Valera Retyunin: Whether or not it matters to your thinking, I hope you are aware that real human beings have survived low temperatures which left them looking just as dead as some of the dogs in early cryonics experiments, and when they awaken, they feel themselves to be the same person as before. This kind of accident still occasionally gets into newspapers. Of course some may argue that they awakened with totally new QEs. Unfortunately that raises questions with the entire idea of QEs. For instance, why is it that we keep the same QE after simply sleeping? We'd certainly believe we did, whether or not we actually did. For Coetzee: A lot depends on just what you mean by "inaccessible" here. We now have methods capable of seeing what goes on inside your brain, admittedly not with the detail that we can say what you're thinking, but CAN say what you're feeling, and get hints about what you're thinking. Although it would raise lots of ire about privacy, etc, there's no special reason why we won't someday have devices that can even say what you're thinking. (Though just like current devices, such as PET scanners or fMRI scanners, your consent to using those devices would still be needed, not in law but in simple practice). Consequence: we could then see you experiencing your qualia. I would agree that we still could not say what it was like to experience your qualia (modulo our ability to see your feelings too). Whether this inability means anything at all to studying consciousness isn't clear at all. I can't see what you're seeing, either, because we're both in different places at different times. This hardly keeps me from understanding how sight occurs. And it's now past midnight here, and I will say: Best wishes and long long life to all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=25114