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Proposition: The Contained Relation is Extensional
The contained relation $\in_X:=\{(z,x)\in X\times X\mid z\in x\}$ is extensional for any set $X.$
Table of Contents
Proofs: 1
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References
Bibliography
- Hoffmann, D.: "Forcing, Eine Einführung in die Mathematik der Unabhängigkeitsbeweise", Hoffmann, D., 2018