Definition:Zermelo-Fraenkel Set Theory/Historical Note

Historical Note on Zermelo-Fraenkel Set Theory
first proposed this supposedly rigorous system of axiomatic set theory in $1900$, in order to confront the paradoxes which the axiom of comprehension lead to.

It was modified by in $1922$.

The system of Zermelo-Fraenkel set theory has formed the basis of most of the formulations of axiomatic set theory which have been created since.