[FOM] Eradicating Evil?

Urs Schreiber urs.schreiber at googlemail.com
Thu Oct 30 13:06:03 EDT 2014

On 10/29/14, Harvey Friedman <hmflogic at gmail.com> wrote in small part:

> [...] as long as your categories have sets of objects, you’ll be able
> to talk about equality of those objects. But I don’t see any way to
> solve that unless your foundational axioms are really about the
> 2-category of categories

No, to solve this one just needs to have foundational axioms that are
at least about the 2-groupoid of groupoids.

The resulting solution is spelled out in Ahrens-Kalulkin-Shulman:


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