25 ideas
5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
10882 | Predicative definitions only refer to entities outside the defined collection [Horsten] |
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] |
10884 | A theory is 'categorical' if it has just one model up to isomorphism [Horsten] |
10885 | Computer proofs don't provide explanations [Horsten] |
10881 | The concept of 'ordinal number' is set-theoretic, not arithmetical [Horsten] |
5736 | No sort of plain language or levels of logic can express modal facts properly [Melia] |
5735 | Maybe names and predicates can capture any fact [Melia] |
15797 | All structures are dispositional, objects are dispositions sets, and events manifest dispositions [Fetzer] |
15800 | All events and objects are dispositional, and hence all structural properties are dispositional [Fetzer] |
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] |
5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
15798 | Kinds are arrangements of dispositions [Fetzer] |
15799 | Lawlike sentences are general attributions of disposition to all members of some class [Fetzer] |