23 ideas
12204 | The logic of metaphysical necessity is S5 [Rumfitt] |
12195 | Soundness in argument varies with context, and may be achieved very informally indeed [Rumfitt] |
12199 | There is a modal element in consequence, in assessing reasoning from suppositions [Rumfitt] |
12201 | We reject deductions by bad consequence, so logical consequence can't be deduction [Rumfitt] |
12194 | Contradictions include 'This is red and not coloured', as well as the formal 'B and not-B' [Rumfitt] |
12198 | Geometrical axioms in logic are nowadays replaced by inference rules (which imply the logical truths) [Rumfitt] |
14532 | A distinctive type of necessity is found in logical consequence [Rumfitt, by Hale/Hoffmann,A] |
12184 | Logical necessity overrules all other necessities [McFetridge] |
15083 | The fundamental case of logical necessity is the valid conclusion of an inference [McFetridge, by Hale] |
15084 | In the McFetridge view, logical necessity means a consequent must be true if the antecedent is [McFetridge, by Hale] |
12180 | Logical necessity requires that a valid argument be necessary [McFetridge] |
12181 | Traditionally, logical necessity is the strongest, and entails any other necessities [McFetridge] |
12183 | It is only logical necessity if there is absolutely no sense in which it could be false [McFetridge] |
12192 | The mark of logical necessity is deduction from any suppositions whatever [McFetridge] |
12193 | Logical necessity is when 'necessarily A' implies 'not-A is contradictory' [Rumfitt] |
12200 | A logically necessary statement need not be a priori, as it could be unknowable [Rumfitt] |
12202 | Narrow non-modal logical necessity may be metaphysical, but real logical necessity is not [Rumfitt] |
12182 | We assert epistemic possibility without commitment to logical possibility [McFetridge] |
12187 | Objectual modal realists believe in possible worlds; non-objectual ones rest it on the actual world [McFetridge] |
12186 | Modal realists hold that necessities and possibilities are part of the totality of facts [McFetridge] |
12203 | If a world is a fully determinate way things could have been, can anyone consider such a thing? [Rumfitt] |
16713 | Philosophers are the forefathers of heretics [Tertullian] |
6610 | I believe because it is absurd [Tertullian] |