PlanetMath: Zermelo-Fraenkel Axioms
PlanetMath
PlanetMath encyclopedia entry stating the Zermelo–Fraenkel axioms of set theory: extensionality, pairing, union, power set, infinity, separation, replacement, and foundation, with a note on adding choice to obtain ZFC. A compact reference for each axiom's precise content.
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The Stanford Encyclopedia of Philosophy is a peer‑reviewed online encyclopedia of philosophy featuring in‑depth, scholarly articles written and regularly updated by experts, including comprehensive coverage of logic topics.
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