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Named after mathematicians Ernst Zermelo and Abraham Fraenkel.
Etymology from Wiktionary, CC BY-SA 4.0.
Zermelo-Fraenkel set theory
Today it means: An axiomatic system that was proposed in the early 20th century in order to formulate a theory of sets free from paradoxes such as Russell's paradox, and became the standard form of axiomatic set theory. Full definition →