[FOM] Replacement

Rupert McCallum rupertmccallum at yahoo.com
Wed Aug 15 19:56:05 EDT 2007

--- Saurav Bhaumik <saurav1b at gmail.com> wrote:

> Exactly, I have the same thing to point here: can the existence of
> Hartogs function proved without Replacement?

It is possible to prove without Replacement that, given any set S,
there exists a well-ordered set T such that a well-ordered set may be
injected into S if and only if it is isomorphic to a proper segment of
T. Using Power and Separation, one forms the set of isomorphism classes
of well-ordered sets that may be injected into S and orders them by

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