Re: Implementable Set Theory and Consistency of ZFC

On Oct 31, 4:24 am, Han de Bruijn <Han.deBru...@xxxxxxxxxxxxxx> wrote:
David C. Ullrich wrote:
If you knew anything about logic you'd know that any consistent
theory with an infinite model has more than one model.

So what's the problem with providing me _one_ example, if you have so
many at your disposal?

An example of what? A consistent theory with more than one infinite
model?

First order Peano arithmetic.

But wait, here's one that's utterly trivial: First order identity
theory!

(Yes, your model is infinite - even though each set in the
model is a finite set, there are infinitely many sets.)

That's true. But these sets do not form a set, rather a proper class or
an improper set, I would say.

They form a proper class in what THEORY?

MoeBlee


.

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