Re: The set of necessary FISONs

On 27.01.2025 15:14, joes wrote:

Am Mon, 27 Jan 2025 12:35:56 +0100 schrieb WM:

On 26.01.2025 23:31, Richard Damon wrote:

 

you can't show that the first FISON isn't a member of the set of
necessary FISONs without assuming the set of necessary FISONs exists.

>
Logic? The set ℕ exists. And I can show that every FISON is neither
necessary nor sufficient to accomplish that aim.

Obviously, but not for infinite sets of FISONs.

>
Also an infinite set needs a first element.