Found in 2 comments on Hacker News
Anon84 · 2020-02-03 · Original thread
JadeNB · 2011-01-20 · Original thread
> Who says infinity is a number?

Not I:

> Oh, or is it maybe a confusion with infinity, which, if we were to try to classify it, would have some claim to being both?

… although the old maxim “What's a number?” “Whatever you treat as a number” (which I encountered in Linderholm's wonderful book (http://www.amazon.com/Mathematics-made-difficult-Carl-Linder...) ) means that the various flavours of infinity, considered as ordinals or cardinals, have some claim to being numbers; and it is often helpful in measure theory, and my own work, to treat even plain old infinity as being a number on at least as good a footing as any other (positive real).

> Once we are confident that infinity is not a number, why would we expect it to have parity?

Why not?

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