33 ideas
5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
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] |
18946 | Unreflectively, we all assume there are nonexistents, and we can refer to them [Reimer] |
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] |
8502 | Realism doesn't explain 'a is F' any further by saying it is 'a has F-ness' [Devitt] |
8503 | The particular/universal distinction is unhelpful clutter; we should accept 'a is F' as basic [Devitt] |
8501 | Quineans take predication about objects as basic, not reference to properties they may have [Devitt] |
17368 | Essentialism concerns the nature of a group, not its category [Devitt] |
17370 | Things that gradually change, like species, can still have essences [Devitt] |
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] |
9354 | Why should necessities only be knowable a priori? That Hesperus is Phosporus is known empirically [Devitt] |
19565 | How could the mind have a link to the necessary character of reality? [Devitt] |
9353 | We explain away a priori knowledge, not as directly empirical, but as indirectly holistically empirical [Devitt] |
9356 | The idea of the a priori is so obscure that it won't explain anything [Devitt] |
19564 | Some knowledge must be empirical; naturalism implies that all knowledge is like that [Devitt] |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
17371 | Some kinds are very explanatory, but others less so, and some not at all [Devitt] |
17369 | We name species as small to share properties, but large enough to yield generalisations [Devitt] |
17367 | Species are phenetic, biological, niche, or phylogenetic-cladistic [Devitt, by PG] |
17372 | The higher categories are not natural kinds, so the Linnaean hierarchy should be given up [Devitt] |
17373 | Species pluralism says there are several good accounts of what a species is [Devitt] |