Source: /cirosantilli/zermelo-fraenkel-set-theory

= Zermelo-Fraenkel set theory
{c}
{title2=ZF}
{wiki=Zermelo–Fraenkel_set_theory}

One of the first <formal proof systems>. This is actually understandable!

This is <Ciro Santilli>-2020 definition of the <foundation of mathematics> (and the only one he had any patience to study at all).

TODO what are its limitations? Why were other systems created?