| 13606 | Humean conceptions of reality drive the adoption of extensional logic [Ellis] |
| 13821 | Extensionality is built into ordinary logic semantics; names have objects, predicates have sets of objects [Bostock] |
| 13362 | If an object has two names, truth is undisturbed if the names are swapped; this is Extensionality [Bostock] |
| 9458 | Extensionalists say that quantifiers presuppose the existence of their objects [Jacquette] |
| 21719 | Extensionalism means what is true of a function is true of coextensive functions [Linsky,B] |