83 ideas
15357 | Philosophy is the most general intellectual discipline [Horsten] |
22611 | Metaphysics can criticise interpretations of science theories, and give good feedback [Ingthorsson] |
15352 | A definition should allow the defined term to be eliminated [Horsten] |
10882 | Predicative definitions only refer to entities outside the defined collection [Horsten] |
15324 | Semantic theories of truth seek models; axiomatic (syntactic) theories seek logical principles [Horsten] |
15323 | Truth is a property, because the truth predicate has an extension [Horsten] |
15374 | Truth has no 'nature', but we should try to describe its behaviour in inferences [Horsten] |
15348 | Propositions have sentence-like structures, so it matters little which bears the truth [Horsten] |
15333 | Modern correspondence is said to be with the facts, not with true propositions [Horsten] |
15337 | The correspondence 'theory' is too vague - about both 'correspondence' and 'facts' [Horsten] |
15334 | The coherence theory allows multiple coherent wholes, which could contradict one another [Horsten] |
15336 | The pragmatic theory of truth is relative; useful for group A can be useless for group B [Horsten] |
15354 | Tarski's hierarchy lacks uniform truth, and depends on contingent factors [Horsten] |
15340 | Tarski Bi-conditional: if you'll assert φ you'll assert φ-is-true - and also vice versa [Horsten] |
15345 | Semantic theories have a regress problem in describing truth in the languages for the models [Horsten] |
15373 | Axiomatic approaches avoid limiting definitions to avoid the truth predicate, and limited sizes of models [Horsten] |
15346 | Axiomatic approaches to truth avoid the regress problem of semantic theories [Horsten] |
15371 | An axiomatic theory needs to be of maximal strength, while being natural and sound [Horsten] |
15332 | 'Reflexive' truth theories allow iterations (it is T that it is T that p) [Horsten] |
15361 | A good theory of truth must be compositional (as well as deriving biconditionals) [Horsten] |
15350 | The Naďve Theory takes the bi-conditionals as axioms, but it is inconsistent, and allows the Liar [Horsten] |
15351 | Axiomatic theories take truth as primitive, and propose some laws of truth as axioms [Horsten] |
15367 | By adding truth to Peano Arithmetic we increase its power, so truth has mathematical content! [Horsten] |
15330 | Friedman-Sheard theory keeps classical logic and aims for maximum strength [Horsten] |
15331 | Kripke-Feferman has truth gaps, instead of classical logic, and aims for maximum strength [Horsten] |
15325 | Inferential deflationism says truth has no essence because no unrestricted logic governs the concept [Horsten] |
15344 | Deflationism skips definitions and models, and offers just accounts of basic laws of truth [Horsten] |
15356 | Deflationism concerns the nature and role of truth, but not its laws [Horsten] |
15368 | This deflationary account says truth has a role in generality, and in inference [Horsten] |
15358 | Deflationism says truth isn't a topic on its own - it just concerns what is true [Horsten] |
15359 | Deflation: instead of asserting a sentence, we can treat it as an object with the truth-property [Horsten] |
15329 | Nonclassical may accept T/F but deny applicability, or it may deny just T or F as well [Horsten] |
22609 | Philosophers accepted first-order logic, because they took science to be descriptive, not explanatory [Ingthorsson] |
15326 | Doubt is thrown on classical logic by the way it so easily produces the liar paradox [Horsten] |
15341 | Deduction Theorem: ψ only derivable from φ iff φ→ψ are axioms [Horsten] |
15328 | A theory is 'non-conservative' if it facilitates new mathematical proofs [Horsten] |
15349 | It is easier to imagine truth-value gaps (for the Liar, say) than for truth-value gluts (both T and F) [Horsten] |
15366 | Satisfaction is a primitive notion, and very liable to semantical paradoxes [Horsten] |
10884 | A theory is 'categorical' if it has just one model up to isomorphism [Horsten] |
15353 | The first incompleteness theorem means that consistency does not entail soundness [Horsten] |
15355 | Strengthened Liar: 'this sentence is not true in any context' - in no context can this be evaluated [Horsten] |
15364 | English expressions are denumerably infinite, but reals are nondenumerable, so many are unnameable [Horsten] |
10885 | Computer proofs don't provide explanations [Horsten] |
10881 | The concept of 'ordinal number' is set-theoretic, not arithmetical [Horsten] |
15360 | ZFC showed that the concept of set is mathematical, not logical, because of its existence claims [Horsten] |
15369 | Set theory is substantial over first-order arithmetic, because it enables new proofs [Horsten] |
15370 | Predicativism says mathematical definitions must not include the thing being defined [Horsten] |
22629 | Basic processes are said to be either physical, or organic, or psychological [Ingthorsson] |
22633 | Indirect realists are cautious about the manifest image, and prefer the scientific image [Ingthorsson] |
15338 | We may believe in atomic facts, but surely not complex disjunctive ones? [Horsten] |
15363 | In the supervaluationist account, disjunctions are not determined by their disjuncts [Horsten] |
15362 | If 'Italy is large' lacks truth, so must 'Italy is not large'; but classical logic says it's large or it isn't [Horsten] |
22606 | Neo-Humeans say there are no substantial connections between anything [Ingthorsson] |
22631 | Properties are said to be categorical qualities or non-qualitative dispositions [Ingthorsson] |
22632 | Physics understands the charge of an electron as a power, not as a quality [Ingthorsson] |
22627 | Compound objects are processes, insofar as change is essential to them [Ingthorsson] |
22613 | Most materialist views postulate smallest indivisible components which are permanent [Ingthorsson] |
22612 | Endurance and perdurance just show the consequences of A or B series time [Ingthorsson] |
22625 | Science suggests causal aspects of the constitution and persistance of objects [Ingthorsson] |
22620 | If causation involves production, that needs persisting objects [Ingthorsson] |
22636 | Every philosophical theory must be true in some possible world, so the ontology is hopeless [Ingthorsson] |
22638 | Worlds may differ in various respects, but no overall similarity of worlds is implied [Ingthorsson] |
15372 | Some claim that indicative conditionals are believed by people, even though they are not actually held true [Horsten] |
15347 | A theory of syntax can be based on Peano arithmetic, thanks to the translation by Gödel coding [Horsten] |
22605 | Humeans describe the surface of causation, while powers accounts aim at deeper explanations [Ingthorsson] |
22607 | Time and space are not causal, but they determine natural phenomena [Ingthorsson] |
22608 | Casuation is the transmission of conserved quantities between causal processes [Ingthorsson] |
22621 | Causation as transfer only works for asymmetric interactions [Ingthorsson] |
22614 | Interventionist causal theory says it gets a reliable result whenever you manipulate it [Ingthorsson] |
22639 | Causal events are always reciprocal, and there is no distinction of action and reaction [Ingthorsson] |
22615 | One effect cannot act on a second effect in causation, because the second doesn't yet exist [Ingthorsson] |
22616 | Empiricists preferred events to objects as the relata, because they have observable motions [Ingthorsson] |
22617 | Science now says all actions are reciprocal, not unidirectional [Ingthorsson] |
22619 | Causes are not agents; the whole interaction is the cause, and the changed compound is the effect [Ingthorsson] |
22635 | People only accept the counterfactual when they know the underlying cause [Ingthorsson] |
22634 | Counterfactuals don't explain causation, but causation can explain counterfactuals [Ingthorsson] |
22637 | Counterfactual theories are false in possible worlds where causation is actual [Ingthorsson] |
22624 | A cause can fail to produce its normal effect, by prevention, pre-emption, finks or antidotes [Ingthorsson] |
22622 | Any process can go backwards or forwards in time without violating the basic laws of physics [Ingthorsson] |
22618 | In modern physics the first and second laws of motion (unlike the third) fail at extremes [Ingthorsson] |
22630 | If particles have decay rates, they can't really be elementary, in the sense of indivisible [Ingthorsson] |
22610 | It is difficult to handle presentism in first-order logic [Ingthorsson] |
1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |