more on this theme | more from this thinker
Full Idea
The counterfactual conditional transmits possibility: (A□→B) ⊃ (◊A⊃◊B). Suppose that if A had held, B would also have held; the if it is possible for A to hold, it is also possible for B to hold.
Gist of Idea
Counterfactual conditionals transmit possibility: (A□→B)⊃(◊A⊃◊B)
Source
Timothy Williamson (Modal Logic within Counterfactual Logic [2010], 1)
Book Ref
'Modality', ed/tr. Hale,B/Hoffman,A [OUP 2010], p.82
| 14531 | Rather than define counterfactuals using necessity, maybe necessity is a special case of counterfactuals [Williamson, by Hale/Hoffmann,A] |
| 14624 | Counterfactual conditionals transmit possibility: (A□→B)⊃(◊A⊃◊B) [Williamson] |
| 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] |
| 14626 | In S5 matters of possibility and necessity are non-contingent [Williamson] |
| 14628 | Imagination is important, in evaluating possibility and necessity, via counterfactuals [Williamson] |