more from Bernard Linsky

### Single Idea 21719

#### [catalogued under 5. Theory of Logic / I. Semantics of Logic / 5. Extensionalism]

Full Idea

With the principle of extensionality anything true of one propositional functions will be true of every coextensive one.

Gist of Idea

Extensionalism means what is true of a function is true of coextensive functions

Source

Bernard Linsky (Russell's Metaphysical Logic [1999], 6.3)

Book Reference

Linsky,Bernard: 'Russell's Metaphysical Logic' [CSLI 1999], p.97