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From: Moebius <invalid@example.invalid>
Newsgroups: sci.logic,sci.math
Subject: Re: Replacement of Cardinality
Date: Thu, 15 Aug 2024 23:36:09 +0200
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Am 15.08.2024 um 20:36 schrieb Jim Burns:

> Translate ¬∃ᴿx(x = 1/0) to

There is nothing to translate. "¬∃ᴿx = 1/0" is just a meaningless 
expression, because "1/0" is a undefined (non-denoting) term/name.

> ¬∃ᴿx: 0⋅x = 1

Now this is a meaningful statement.

> Prove that.

Indeed! :-)

For this we might assume

      ∃ᴿx: 0⋅x = 1

and try to derive a contradiction from this assumption.

->Proof by contradiction (RRA).