Xref: utzoo comp.edu:3709 uw.general:1957 Path: utzoo!attcan!lsuc!watmath!maytag!aftermath!water!nmouawad From: nmouawad@water.waterloo.edu (Naji Mouawad) Newsgroups: comp.edu,uw.general Subject: Re: Recursion Summary Message-ID: <1990Oct25.164113.2453@water.waterloo.edu> Date: 25 Oct 90 16:41:13 GMT References: <1990Oct23.211651.10227@contact.uucp> <9868@milton.u.washington.edu> <9882@milton.u.washington.edu> <9893@milton.u.washington.edu> <1990Oct25.145621.13691@watdragon.waterloo.edu> Distribution: na Organization: University of Waterloo Lines: 46 In article <1990Oct25.145621.13691@watdragon.waterloo.edu> ccplumb@spurge.uwaterloo.ca (Colin Plumb) writes: [Part deleted] >Turing machines are fully capable of recursion. Nobody has found a >buildable machine which is fundamentally more capable that a Turing >machine, i.e. to the best of my knowledge, my own brain is ~~~~~~~~~~~~~~~~ >Turing-equivalent (although it would take a *damn* fast Turing ~~~~~~~~~~~~~~~~~ >machine and very clever software!). [Part deleted] --Colin As a side note, the underlined sentence implies that the Cartesian dualism is true and that the Kantian boundary between physics and metaphysic can be removed. That the current perception of the brain can be modeled with Turing machines is true, but that does not mean that the various boundaries imposed by the digitalisation of the brain (in order to represent it as a Turing machine with a countable _not necessarly finite _ number of states) is 'accurate'. It may be that the continuous process of the brain activity can be better represented by some other mechanism than the Turing machine (undecidable question ?). More importantly, mathematics taught us that there is just no way to represent all the reals by rationals. Another way of saying the same thing is that reality (analog process) cannot be entirely 'grabed' by reason (digital process). Thus, if the Cartesian dualism is false (meaning that the thinking process depends intimatly on the supporting hardware _ the brain _) then Turing machines are a pale comparison (in power and flexibility ;) ) to the brain. --Naji. P.S. Could someone come up with a Pumping Lemma for the brain ? -- ---------------+------------------------------------------- | Naji Mouawad | nmouawad@water.waterloo.edu | | University |-------------------------------------------| | Of Waterloo | "Thanks God, we cannot prove He Exists." |