X-Message-Number: 14986 Date: Tue, 21 Nov 2000 22:11:38 +0000 From: "Joseph Kehoe" <> Subject: turing and brains Hi, unable to reply to discussion in depth. Bit busy at work at the mo. but I will reply as soon as I have time Just a few points: 1. Turing machine is a mathematical model of algorithms. (this has been stated) 2. Very Weak Claim we cannot model brains now TRUE Weak Claim Current architectures will never model brains sometimes stated as We will need a whole new type of CPU to model brains (some kind of analog Quantum based thingy) Digital Computers can model analog processes to an arbitrary degree There is no proof than quantum mechanics play any part in any functioning of the brain. It is only "basic" classical atom interaction. opinion: We will never see any proof that quantum thingys are responsible for consciousness. I see this arguement as a last ditch effort to replace souls with an equivalent scientific version. There is no proof of quantum consciousness but there is lots of stuff on emergent behavious and complexity. This is much much more likely. When you reach a certain complexity interesting things happen. Plenty of examples and firm logical basis. Strong Claim Turing machine may but they will always be too slow Turing machines have no time bounds placed on their behaviour. The real time claim is a different one. We may be turing machines but we are way to fast to exist as Turing machines;-) Unless you can prove that brains are some incredibly NP-Hard type machines this is not the case. And unless we reach some fundamental limit in CPU speedup before the second half of this century this will not be true. I do not see us reaching that limit. either we are turing machines or we are not which leads us to... Very Strong claim Turing machines cannot model brains We are not algorithms? ummm... Again what makes us so special. We are the most complex things we know but what is the special "ether" that we have that other things do not have? We are physical and chemical processes just like any other. See emergent complexity But is open to discussion. I do not believe that this is true. It would make no sense if it were true. We do exist so we must be possible. I do not see speed as a problem within 50 years. If we can model a neuron then why can we not model a brain. This only makes sense if you are saying that brains are neurons plus a mysterious unknowable other thingy (soul!). It would be nice to believe that we are special different from all else but there is no proof anywhere of this and there never will be (also opinion). As I said the quantum thingy seems a last refuge of "soulists" I may be wrong but I have not seen any logal argument to the contrary (but then I would say that) If I missed anything whoops but only had time to speed read the replies p.s. Penroses (the Emp. new mind) discription of Turing machines is the worst I have ever read!!! Joseph. ---------------------------------------------- Joseph Kehoe, MSc Raven Internet Technologies Ltd. ph: +353 503 52450 www.raven.ie Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=14986