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Re: A Questionable Foundation

Subject: Re: A Questionable Foundation
From: "MoeBlee"
Date: 8 Aug 2006 16:49:17 -0700
Newsgroups: sci.logic, sci.math
Russell Easterly wrote:
> So, not only is N its own predecessor, N is also its own successor.
> Good thing you have the axiom of regularity so you can "prove"
> N is not a member of itself.

No ordinal is its own predecessor or its own successor.

And that no ordinal is a member of itself is a theorem of Z set theory
without the axiom of regularity.

But, it's a good thing for you that you can prove anything you want,
just by that special inference rule you have that says anything you
want to be proven is proven.

MoeBlee


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