Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site rabbit.UUCP Path: utzoo!linus!decvax!harpo!eagle!allegra!alice!rabbit!ss From: ss@rabbit.UUCP Newsgroups: net.math Subject: Re: A new paradox? Message-ID: <1932@rabbit.UUCP> Date: Thu, 15-Sep-83 09:02:21 EDT Article-I.D.: rabbit.1932 Posted: Thu Sep 15 09:02:21 1983 Date-Received: Fri, 16-Sep-83 00:23:16 EDT References: <406@5941ux.UUCP> Organization: Bell Labs, Murray Hill Lines: 30 ------------------------------- Theorem: In any set of N elements (N >= 1), all elements in the set are equal. Proof: By induction on N. For N=1, the theorem is clearly true. If N>1, then we can inductively assume that the theorem is true for all sets of N-1 elements. Select a set of N elements x(1), ..., x(N). The elements x(1), ..., x(N-1) constitute a set of N-1 elements, which by the inductive hypothesis are all equal. Similarly, the elements x(2), ..., x(N) constitute a set of N-1 elements, which by the inductive hypothesis are all equal. Consequently, by the transitive property of equality, all the elements x(1), x(2), ..., x(N-1), x(N) are equal. This completes the proof. Where's the fallacy? Dave Ellis / Bell Labs, Piscataway NJ ------------------ What are you trying to prove?? All that the above says is that IF x(1) -- x(N) are in the set of equals THEN all N-1 element sub-sets of this set are in the set of equals and (here is the nice part) THEREFORE x(1) --- x(N) are in the set of equals. It certainly does not prove that ANY N element set has equal elements. Sharad Singhal