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Topic: § 454 Equality and the axioms of natural numbers
Replies: 30   Last Post: Mar 23, 2014 2:41 PM

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 Virgil Posts: 8,833 Registered: 1/6/11
Re: � 454 Equality and the axioms of natural numbers
Posted: Mar 22, 2014 5:38 PM

mueckenh@rz.fh-augsburg.de wrote:

> On Saturday, 22 March 2014 09:57:53 UTC+1, Virgil wrote:
>
>

> > > How can the reader determine whether two numbers (or members) are equal
> > > or

> >
> > > not equal. What is the definition of equality used here?
> >
> >
> >
> > Identity, of course!

>
> Is identity equal to (numerical) equality?

See below.

> Is identity identical to (numerical) equality?

See be;ow.
>
> >
> > Since "x" and "y" and "f(x) and "f(y)" are merely names, x = y if and
> > only if "x" and "y" are merely different names for the same thing,
> > and f(x) = f(y) if and only if "f(x)" and "f(y)" are merely different
> > names for the same thing.

What part of the above does WM not understand?
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