14 ideas
15086 | Absolute necessity might be achievable either logically or metaphysically [Hale] |
8261 | Maybe not-p is logically possible, but p is metaphysically necessary, so the latter is not absolute [Hale] |
15080 | 'Relative' necessity is just a logical consequence of some statements ('strong' if they are all true) [Hale] |
15081 | A strong necessity entails a weaker one, but not conversely; possibilities go the other way [Hale] |
15082 | Metaphysical necessity says there is no possibility of falsehood [Hale] |
15085 | 'Broadly' logical necessities are derived (in a structure) entirely from the concepts [Hale] |
15088 | Logical necessities are true in virtue of the nature of all logical concepts [Hale] |
10993 | Ramsey's Test: believe the consequent if you believe the antecedent [Ramsey, by Read] |
14279 | Asking 'If p, will q?' when p is uncertain, then first add p hypothetically to your knowledge [Ramsey] |
15087 | Conceptual necessities are made true by all concepts [Hale] |
6894 | Mental terms can be replaced in a sentence by a variable and an existential quantifier [Ramsey] |
20239 | Unlike us, the early Greeks thought envy was a good thing, and hope a bad thing [Hesiod, by Nietzsche] |
9418 | All knowledge needs systematizing, and the axioms would be the laws of nature [Ramsey] |
9420 | Causal laws result from the simplest axioms of a complete deductive system [Ramsey] |