Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!burl!ulysses!gamma!epsilon!zeta!sabre!petrus!bellcore!decvax!genrad!panda!talcott!harvard!seismo!umcp-cs!aplcen!jhunix!ins_ampm From: ins_ampm@jhunix.UUCP (Michael P McKenna) Newsgroups: net.puzzle Subject: Re: truth machine clarification**2 Message-ID: <2109@jhunix.UUCP> Date: Wed, 5-Mar-86 18:41:16 EST Article-I.D.: jhunix.2109 Posted: Wed Mar 5 18:41:16 1986 Date-Received: Sat, 8-Mar-86 02:52:03 EST References: <423@watdragon.UUCP> <2664@pucc-h> <394@link.UUCP> Reply-To: ins_ampm@jhunix.ARPA (Michael P McKenna) Organization: Johns Hopkins Univ. Computing Ctr. Lines: 27 In article <394@link.UUCP> msb@link.UUCP writes: >> In article <423@watdragon.UUCP> gawilson@watdragon.UUCP (Graham Wilson) writes: >> >Consider a machine which is used to create true sentences (for example, >> >the sentence "A dog is a dog" is true). If the machine is "complete", >> >then it could, given time, produce the set of ALL true sentences. If the >> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >> >machine is "consistent", then all the sentences that it produces will be >> >true. >> > >> >Question: Can such a machine exist (even in theory)? >> >> The machine cannot produce the set of ALL true sentences unless that set >> is finite. I think you meant to say any given true sentence would eventually >> be produced by the machine. >> -- >> Dave Seaman pur-ee!pucc-h!ags > >You can't even guarantee that any given true sentence would eventually be >produced by the machine unless the set is finite. You mean countable. If the set is countable there exists a 1 to 1 correspondence with the set of positive integers. Thus each true statement can be associated with a unique integer. We need only specify that the machine produces the statements in this order to guarantee that any true statement is eventually produced. Dwight S. Wilson