27 ideas
5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
9331 | How do we determine which of the sentences containing a term comprise its definition? [Horwich] |
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] |
5740 | Second-order logic needs second-order variables and quantification into predicate position [Melia] |
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] |
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] |
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] |
9333 | A priori belief is not necessarily a priori justification, or a priori knowledge [Horwich] |
9342 | Understanding needs a priori commitment [Horwich] |
9332 | Meaning is generated by a priori commitment to truth, not the other way around [Horwich] |
9341 | Meanings and concepts cannot give a priori knowledge, because they may be unacceptable [Horwich] |
9334 | If we stipulate the meaning of 'number' to make Hume's Principle true, we first need Hume's Principle [Horwich] |
9339 | A priori knowledge (e.g. classical logic) may derive from the innate structure of our minds [Horwich] |
9329 | Justification is coherence with a background system; if irrefutable, it is knowledge [Lehrer] |
9330 | Generalization seems to be more fundamental to minds than spotting similarities [Lehrer] |
9328 | All conscious states can be immediately known when attention is directed to them [Lehrer] |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |