Statements (14)
| Predicate | Object |
|---|---|
| gptkbp:instanceOf |
gptkb:Titan
gptkb:set_theory |
| gptkbp:field |
gptkb:set_theory
|
| gptkbp:importantFor |
foundation of modern set theory
|
| gptkbp:introduced |
gptkb:Ernst_Zermelo
|
| gptkbp:relatedTo |
gptkb:axiom_of_pairing
gptkb:axiom_of_regularity |
| gptkbp:state |
Two sets are equal if and only if they have the same elements.
|
| gptkbp:symbol |
∀A ∀B [∀x (x ∈ A ↔ x ∈ B) → A = B]
|
| gptkbp:usedIn |
gptkb:Zermelo–Fraenkel_set_theory
gptkb:von_Neumann–Bernays–Gödel_set_theory |
| gptkbp:bfsParent |
gptkb:Zermelo–Fraenkel_axioms
|
| gptkbp:bfsLayer |
6
|
| https://www.w3.org/2000/01/rdf-schema#label |
axiom of extensionality
|