18 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] |
15148 | Powers give explanations, without being necessary for some class membership [Chakravartty] |
15145 | A kind essence is the necessary and sufficient properties for membership of a class [Chakravartty] |
15147 | Cluster kinds are explained simply by sharing some properties, not by an 'essence' [Chakravartty] |
14532 | A distinctive type of necessity is found in logical consequence [Rumfitt, by Hale/Hoffmann,A] |
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] |
12203 | If a world is a fully determinate way things could have been, can anyone consider such a thing? [Rumfitt] |
20921 | How can we state relativism of sweet and sour, if they have no determinate nature? [Theophrastus] |
15144 | Explanation of causal phenomena concerns essential kinds - but also lack of them [Chakravartty] |
15146 | Some kinds, such as electrons, have essences, but 'cluster kinds' do not [Chakravartty] |
15151 | Many causal laws do not refer to kinds, but only to properties [Chakravartty] |