10 ideas
7726 | Aristotelian logic dealt with inferences about concepts, and there were also proposition inferences [Weiner] |
14626 | In S5 matters of possibility and necessity are non-contingent [Williamson] |
19400 | Possibles demand existence, so as many of them as possible must actually exist [Leibniz] |
19401 | God's sufficient reason for choosing reality is in the fitness or perfection of possibilities [Leibniz] |
14625 | Necessity is counterfactually implied by its negation; possibility does not counterfactually imply its negation [Williamson] |
14623 | Strict conditionals imply counterfactual conditionals: □(A⊃B)⊃(A□→B) [Williamson] |
14624 | Counterfactual conditionals transmit possibility: (A□→B)⊃(◊A⊃◊B) [Williamson] |
14531 | Rather than define counterfactuals using necessity, maybe necessity is a special case of counterfactuals [Williamson, by Hale/Hoffmann,A] |
19402 | The actual universe is the richest composite of what is possible [Leibniz] |
14628 | Imagination is important, in evaluating possibility and necessity, via counterfactuals [Williamson] |