4 ideas
17743 | De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki] |
10710 | We accept substance, to avoid infinite backwards chains of meaning [Wittgenstein, by Potter] |
14286 | In nearby worlds where A is true, 'if A,B' is true or false if B is true or false [Stalnaker] |
14285 | A possible world is the ontological analogue of hypothetical beliefs [Stalnaker] |