47 ideas
13395 | If an analysis shows the features of a concept, it doesn't seem to 'reduce' the concept [Jubien] |
10301 | The axiom of choice is controversial, but it could be replaced [Shapiro] |
13378 | It is a mistake to think that the logic developed for mathematics can clarify language and philosophy [Jubien] |
10588 | First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro] |
10298 | Some say that second-order logic is mathematics, not logic [Shapiro] |
10299 | If the aim of logic is to codify inferences, second-order logic is useless [Shapiro] |
10300 | Logical consequence can be defined in terms of the logical terminology [Shapiro] |
13402 | We only grasp a name if we know whether to apply it when the bearer changes [Jubien] |
13405 | The baptiser picks the bearer of a name, but social use decides the category [Jubien] |
13399 | Examples show that ordinary proper names are not rigid designators [Jubien] |
13398 | We could make a contingent description into a rigid and necessary one by adding 'actual' to it [Jubien] |
13392 | Philosophers reduce complex English kind-quantifiers to the simplistic first-order quantifier [Jubien] |
10290 | Second-order variables also range over properties, sets, relations or functions [Shapiro] |
10590 | Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro] |
10292 | Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro] |
10296 | The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro] |
10297 | The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro] |
10294 | Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro] |
13404 | To exist necessarily is to have an essence whose own essence must be instantiated [Jubien] |
17304 | As causation links across time, grounding links the world across levels [Schaffer,J] |
17306 | If ground is transitive and irreflexive, it has a strict partial ordering, giving structure [Schaffer,J] |
13386 | If objects are just conventional, there is no ontological distinction between stuff and things [Jubien] |
13403 | The category of Venus is not 'object', or even 'planet', but a particular class of good-sized object [Jubien] |
10591 | Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro] |
13375 | The idea that every entity must have identity conditions is an unfortunate misunderstanding [Jubien] |
13393 | Any entity has the unique property of being that specific entity [Jubien] |
13388 | It is incoherent to think that a given entity depends on its kind for its existence [Jubien] |
13384 | Objects need conventions for their matter, their temporal possibility, and their spatial possibility [Jubien] |
13385 | Basically, the world doesn't have ready-made 'objects'; we carve objects any way we like [Jubien] |
13383 | If the statue is loved and the clay hated, that is about the object first qua statue, then qua clay [Jubien] |
13400 | If one entity is an object, a statue, and some clay, these come apart in at least three ways [Jubien] |
13401 | The idea of coincident objects is a last resort, as it is opposed to commonsense naturalism [Jubien] |
13380 | Parts seem to matter when it is just an object, but not matter when it is a kind of object [Jubien] |
13376 | We should not regard essentialism as just nontrivial de re necessity [Jubien] |
13381 | Thinking of them as 'ships' the repaired ship is the original, but as 'objects' the reassembly is the original [Jubien] |
13382 | Rearranging the planks as a ship is confusing; we'd say it was the same 'object' with a different arrangement [Jubien] |
13379 | If two objects are indiscernible across spacetime, how could we decide whether or not they are the same? [Jubien] |
13394 | Entailment does not result from mutual necessity; mutual necessity ensures entailment [Jubien] |
13391 | Modality concerns relations among platonic properties [Jubien] |
13374 | To analyse modality, we must give accounts of objects, properties and relations [Jubien] |
13389 | The love of possible worlds is part of the dream that technical logic solves philosophical problems [Jubien] |
13390 | Possible worlds don't explain necessity, because they are a bunch of parallel contingencies [Jubien] |
17308 | Explaining 'Adam ate the apple' depends on emphasis, and thus implies a contrast [Schaffer,J] |
13396 | Analysing mental concepts points to 'inclusionism' - that mental phenomena are part of the physical [Jubien] |
13377 | First-order logic tilts in favour of the direct reference theory, in its use of constants for objects [Jubien] |
17305 | I take what is fundamental to be the whole spatiotemporal manifold and its fields [Schaffer,J] |
17307 | Nowadays causation is usually understood in terms of equations and variable ranges [Schaffer,J] |