30 ideas
5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
8952 | We reach 'reflective equilibrium' when intuitions and theory completely align [Fisher] |
14231 | We should always apply someone's theory of meaning to their own utterances [Liggins] |
5737 | Predicate logic has connectives, quantifiers, variables, predicates, equality, names and brackets [Melia] |
5744 | First-order predicate calculus is extensional logic, but quantified modal logic is intensional (hence dubious) [Melia] |
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] |
8950 | Logic formalizes how we should reason, but it shouldn't determine whether we are realists [Fisher] |
5740 | Second-order logic needs second-order variables and quantification into predicate position [Melia] |
14232 | We normally formalise 'There are Fs' with singular quantification and predication, but this may be wrong [Liggins] |
5741 | If every model that makes premises true also makes conclusion true, the argument is valid [Melia] |
5735 | Maybe names and predicates can capture any fact [Melia] |
5736 | No sort of plain language or levels of logic can express modal facts properly [Melia] |
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] |
14233 | Nihilists needn't deny parts - they can just say that some of the xs are among the ys [Liggins] |
5746 | The Identity of Indiscernibles is contentious for qualities, and trivial for non-qualities [Melia] |
5738 | We may be sure that P is necessary, but is it necessarily necessary? [Melia] |
5732 | 'De re' modality is about things themselves, 'de dicto' modality is about propositions [Melia] |
5739 | Sometimes we want to specify in what ways a thing is possible [Melia] |
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] |
5734 | Possible worlds make it possible to define necessity and counterfactuals without new primitives [Melia] |
5742 | In possible worlds semantics the modal operators are treated as quantifiers [Melia] |
5743 | If possible worlds semantics is not realist about possible worlds, logic becomes merely formal [Melia] |
5749 | Possible worlds could be real as mathematics, propositions, properties, or like books [Melia] |
5751 | The truth of propositions at possible worlds are implied by the world, just as in books [Melia] |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |