# axiom of extensionality

> axiom of Zermelo–Fraenkel set theory asserting that set equality is determined by the membership relation

**Wikidata**: [Q740424](https://www.wikidata.org/wiki/Q740424)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Axiom_of_extensionality)  
**Source**: https://4ort.xyz/entity/axiom-of-extensionality


## References

1. Freebase Data Dumps. 2013
2. BabelNet