6 ideas
16456 | For modality Lewis rejected boxes and diamonds, preferring worlds, and an index for the actual one [Lewis, by Stalnaker] |
3425 | Reduction has been defined as deriving one theory from another by logic and maths [Nagel,E, by Kim] |
13768 | Validity can preserve certainty in mathematics, but conditionals about contingents are another matter [Edgington] |
13770 | There are many different conditional mental states, and different conditional speech acts [Edgington] |
13764 | Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington] |
13765 | 'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington] |