Re: ---HOW to prove that Axiom of CHOICE is not used in a proof

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Article #14127

#14127

From: Robert Israel
Date: Tue, 31 May 1994 21:42

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In article <miha0008-300594043556@dialup-3-187.gw.umn.edu>  
miha0008@gold.tc.umn.edu (H. Reiju Mihara) writes:
> Q2. How do we prove that a certain proposition _can_ be proved without
> using AC?  

Usually (though not always) a proof that a proposition can be
proved can readily be transformed into a proof of the proposition itself.

> Q3. What is a basic strategy for proving a proposition (that can be proved 
> without AC) in such a way that it is evident that AC is not used?

What is a basic strategy for proving a proposition?  Go to grad school,
understand the standard theorems in the subject, ...
What kind of an answer could you possibly expect?

--
Robert Israel                            israel@math.ubc.ca
Department of Mathematics             
University of British Columbia
Vancouver, BC, Canada V6T 1Y4

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From: israel@math.ubc.ca (Robert Israel)
Newsgroups: fj.sci.math,sci.logic
Subject: Re: ---HOW to prove that Axiom of CHOICE is not used in a proof
Date: 31 May 1994 21:42:18 GMT
Organization: The University of British Columbia
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