X-Message-Number: 21392 Date: Tue, 11 Mar 2003 23:26:55 -0700 From: Mike Perry <> Subject: Symbols and Awareness Thomas Donaldson writes: >Your discussion of awareness in computers has several empty spots. >First of all, where in the Turing test is awareness even discussed? It isn't. I brought up the Turing Test because (1) a system that passes it at least will *seem* to have awareness, but also (2) to note that, in the example I considered, something *more* than passing the Turing test is involved. >Second, you clearly believe that there is no valid test for >awareness. Depends on the circumstances. Also, if I am said to "believe" something, it is not the same as "believe dogmatically"--I could be wrong (yes, even more often than water freezes in the hot sun ;-). >Yet we already have (very poor focus) ways to read >brains as they work. This ability is improving. So who says I >could not find out whether or not you were aware? I'm not disputing that there could be ways of testing, "behind the scenes," whether a brain is showing awareness or not. The real question is whether some other system that seems, on the face of it, to be aware, really is so or not. Finding out how a brain works would not, in and of itself, prove that something that works differently could not be aware. Suppose we have a system, call it S, that simulates the brain at a deep level, though S itself is computational and symbolic. S, then, passes reasonable tests for awareness just like the real brain. Not only does it communicate, but internal brain structures and their associated functioning: neurons, synapses, molecular architectures, and so on, are all isomorphically reproduced. Again, though, S is "only" a (very advanced and sophisticated) computational device, and, at its *own* deepest level, is clearly not functioning just like a brain. But I maintain that, under the circumstances and barring some fundamental new discovery about reality, there would be no reasonable proof or compelling argument that S does not have true awareness. >I'm not saying that our brains work by some magical process at >all. They work by processes we are coming to understand; and >their working is much more like the operation of a piston >or the slow burning of a fire than like the inevitably symbolic >operations of a computer. You seem to draw a sharp distinction between "inevitably symbolic operations" and other processes such as fire or a piston's pushing. But consider this possibility. Nature herself is, at the deepest level, also "symbolic." Why would we suspect this? Because that seems to be the take-home message of quantum mechanics. Things happen in discrete jumps, rather as they do in a computer. So, even though fundamentally "unsymbolic" processing seems to exist, this is really only an illusion caused by the scale and complexity of what goes on. In the same way, a gas seems to be a smooth fluid, infinitely divisible, but we know it isn't that at all, but resolves into discrete units (molecules) on a fine scale. >That is why I have said and are saying >that computers by their nature cannot be aware. I don't see it that way, and, if things are "symbolic" at the deepest level as suggested above, it especially undercuts your claim. >...And so far as you can build a machine which works like a brain >rather than a computer, working not with symbols at all but >with the world, Once again, though, it seems the world itself is just an ongoing computation using "symbols" of a sort; David Deutsch makes this point in *The Fabric of Reality*. Another thought is that the term "symbol" itself may be a stumbling block for the points I've been trying to make, because we naturally think a symbol is something that has to "stand for" something else, that is to say, we have to assign a meaning. But really that's not so. Instead of "symbols" I could have used "letters"--understood to be chosen from a finite alphabet--or just "bits"--which are the most convenient since there are two letters in the alphabet and two only. Individually, a bit (0 or 1, say) can be called a "symbol" but it really doesn't have to mean anything, except that it is different from its opposite (0 and 1 are different that is). Here it's not the individual bits that have meaning, but the *patterns* they are formed into, and these patterns are not just arbitrary. We immediately note the difference, for example, between a pattern that looks random and one that is structured in some simple way, such as, for example, having all 0's or all 1's. The patterns may have assigned meanings, it's true, but could reasonably suggest their own meanings also, as if, for example, we were to represent the prime numbers according to some simple encoding. Other math concepts could similarly be represented, and you could go from there. Mike Perry Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=21392