Re: A simple question?

zuhair wrote:
Hi,

For w={ 0,1,2,3,....} , is P(w) a well ordered set?

You mean the power set of omega?

Your question is not complete.

Under what axioms?

A set is well ordered if there is a well ordering of the set.

With the axiom of choice added to the ZF axioms, every set has a well
ordering.

As I understand, ZF without the axiom of choice cannot prove that the
power set of omega has a well ordering.

MoeBlee

.

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