Re: Request for Review and Tutorage of Amateur Proof

On Dec 18, 5:25 pm, MoeBlee <jazzm...@xxxxxxxxxxx> wrote:
Note (just in case it is relevent later). Since 'x' here is just an
existentially instantiated variable, you've not actually defined a
constant 'w' but rather set the variable 'w' with w=Ux.

Do I need to define a constant? Isn't the proof general enough to
establish a property of any limit ordinal?


I'm not sure what your lub argument is exactly in its details, but we
do have the theorem that the union of a set of ordinals is an ordinal,
so w is an ordinal.

The LUB argument comes from: If x is an ordinal, then Ux is an
ordinal, which is also the LUB.

I take it that 'c' stands for proper subset.

Yes.

What is the main book you're working in?

A tour through mathematical logic, chapter 2.

Scott
.

Relevant Pages

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