more on this theme | more from this thinker
Full Idea
There will be a legitimate notion of 'logical' necessity only if there is a notion of necessity which attaches to the claim, concerning a deductively valid argument, that if the premisses are true then so is the conclusion.
Gist of Idea
Logical necessity requires that a valid argument be necessary
Source
Ian McFetridge (Logical Necessity: Some Issues [1986], §1)
Book Ref
-: 'Aristotelian Society' [], p.136
A Reaction
He quotes Aristotle's Idea 11148 in support. Is this resting a stronger idea on a weaker one? Or is it the wrong way round? We endorse validity because we see the necessity; we don't endorse necessity because we see 'validity'.
Related Idea
Idea 11148 Deduction is when we suppose one thing, and another necessarily follows [Aristotle]
| 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] |
| 12182 | We assert epistemic possibility without commitment to logical possibility [McFetridge] |
| 12184 | Logical necessity overrules all other necessities [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] |
| 12192 | The mark of logical necessity is deduction from any suppositions whatever [McFetridge] |