31 ideas
| 8952 | We reach 'reflective equilibrium' when intuitions and theory completely align [Fisher] |
| 4901 | Truth has to be correspondence to facts, and a match between relations of ideas and relations in the world [Perry] |
| 8943 | Three-valued logic says excluded middle and non-contradition are not tautologies [Fisher] |
| 8945 | Fuzzy logic has many truth values, ranging in fractions from 0 to 1 [Fisher] |
| 8951 | Classical logic is: excluded middle, non-contradiction, contradictions imply all, disjunctive syllogism [Fisher] |
| 14249 | Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley] |
| 10830 | Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos] |
| 10829 | A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos] |
| 8950 | Logic formalizes how we should reason, but it shouldn't determine whether we are realists [Fisher] |
| 10832 | '∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos] |
| 10834 | Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos] |
| 13841 | Why should compactness be definitive of logic? [Boolos, by Hacking] |
| 10833 | Many concepts can only be expressed by second-order logic [Boolos] |
| 8946 | We could make our intuitions about heaps precise with a million-valued logic [Fisher] |
| 8944 | Vagueness can involve components (like baldness), or not (like boredom) [Fisher] |
| 4885 | Identity is a very weak relation, which doesn't require interdefinability, or shared properties [Perry] |
| 8941 | We can't explain 'possibility' in terms of 'possible' worlds [Fisher] |
| 8947 | If all truths are implied by a falsehood, then not-p might imply both q and not-q [Fisher] |
| 8949 | In relevance logic, conditionals help information to flow from antecedent to consequent [Fisher] |
| 4899 | Possible worlds thinking has clarified the logic of modality, but is problematic in epistemology [Perry] |
| 4898 | Possible worlds are indices for a language, or concrete realities, or abstract possibilities [Perry] |
| 4887 | We try to cause other things to occur by causing mental events to occur [Perry] |
| 4884 | Brain states must be in my head, and yet the pain seems to be in my hand [Perry] |
| 4888 | It seems plausible that many animals have experiences without knowing about them [Perry] |
| 4891 | If epiphenomenalism just says mental events are effects but not causes, it is consistent with physicalism [Perry] |
| 4900 | Prior to Kripke, the mind-brain identity theory usually claimed that the identity was contingent [Perry] |
| 4892 | If physicalists stick with identity (not supervenience), Martian pain will not be like ours [Perry] |
| 4889 | Although we may classify ideas by content, we individuate them differently, as their content can change [Perry] |
| 4896 | The intension of an expression is a function from possible worlds to an appropriate extension [Perry] |
| 4897 | A proposition is a set of possible worlds for which its intension delivers truth [Perry] |
| 4890 | A sharp analytic/synthetic line can rarely be drawn, but some concepts are central to thought [Perry] |