100 ideas
| 17016 | Philosophy must abstract from the senses [Newton] |
| 15357 | Philosophy is the most general intellectual discipline [Horsten] |
| 15352 | A definition should allow the defined term to be eliminated [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] |
| 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] |
| 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] |
| 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] |
| 18806 | Frege thought traditional categories had psychological and linguistic impurities [Frege, by Rumfitt] |
| 15329 | Nonclassical may accept T/F but deny applicability, or it may deny just T or F as well [Horsten] |
| 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] |
| 8490 | First-level functions have objects as arguments; second-level functions take functions as arguments [Frege] |
| 8492 | Relations are functions with two arguments [Frege] |
| 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] |
| 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] |
| 18079 | Newton developed a kinematic approach to geometry [Newton, by Kitcher] |
| 15364 | English expressions are denumerably infinite, but reals are nondenumerable, so many are unnameable [Horsten] |
| 18082 | Quantities and ratios which continually converge will eventually become equal [Newton] |
| 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] |
| 8487 | Arithmetic is a development of logic, so arithmetical symbolism must expand into logical symbolism [Frege] |
| 15370 | Predicativism says mathematical definitions must not include the thing being defined [Horsten] |
| 18899 | Frege takes the existence of horses to be part of their concept [Frege, by Sommers] |
| 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] |
| 4028 | Frege allows either too few properties (as extensions) or too many (as predicates) [Mellor/Oliver on Frege] |
| 17011 | I suspect that each particle of bodies has attractive or repelling forces [Newton] |
| 8489 | The concept 'object' is too simple for analysis; unlike a function, it is an expression with no empty place [Frege] |
| 17028 | Particles mutually attract, and cohere at short distances [Newton] |
| 17014 | The place of a thing is the sum of the places of its parts [Newton] |
| 15372 | Some claim that indicative conditionals are believed by people, even though they are not actually held true [Horsten] |
| 17546 | If you changed one of Newton's concepts you would destroy his whole system [Heisenberg on Newton] |
| 17027 | Science deduces propositions from phenomena, and generalises them by induction [Newton] |
| 17022 | We should admit only enough causes to explain a phenomenon, and no more [Newton] |
| 17021 | Natural effects of the same kind should be assumed to have the same causes [Newton] |
| 17026 | From the phenomena, I can't deduce the reason for the properties of gravity [Newton] |
| 9947 | Concepts are the ontological counterparts of predicative expressions [Frege, by George/Velleman] |
| 10319 | An assertion about the concept 'horse' must indirectly speak of an object [Frege, by Hale] |
| 8488 | A concept is a function whose value is always a truth-value [Frege] |
| 9948 | Unlike objects, concepts are inherently incomplete [Frege, by George/Velleman] |
| 4972 | I may regard a thought about Phosphorus as true, and the same thought about Hesperus as false [Frege] |
| 15347 | A theory of syntax can be based on Peano arithmetic, thanks to the translation by Gödel coding [Horsten] |
| 6421 | Newton's four fundamentals are: space, time, matter and force [Newton, by Russell] |
| 13470 | Mass is central to matter [Newton, by Hart,WD] |
| 17020 | An attraction of a body is the sum of the forces of their particles [Newton] |
| 23012 | Newtonian causation is changes of motion resulting from collisions [Newton, by Baron/Miller] |
| 17008 | You have discovered that elliptical orbits result just from gravitation and planetary movement [Newton, by Leibniz] |
| 17010 | We have given up substantial forms, and now aim for mathematical laws [Newton] |
| 17023 | I am not saying gravity is essential to bodies [Newton] |
| 15866 | Newton reclassified vertical motion as violent, and unconstrained horizontal motion as natural [Newton, by Harré] |
| 15958 | Inertia rejects the Aristotelian idea of things having natural states, to which they return [Newton, by Alexander,P] |
| 17017 | 1: Bodies rest, or move in straight lines, unless acted on by forces [Newton] |
| 17018 | 2: Change of motion is proportional to the force [Newton] |
| 17019 | 3: All actions of bodies have an equal and opposite reaction [Newton] |
| 20968 | Newton's Third Law implies the conservation of momentum [Newton, by Papineau] |
| 17547 | Newton's idea of force acting over a long distance was very strange [Heisenberg on Newton] |
| 20966 | Newton introduced forces other than by contact [Newton, by Papineau] |
| 20967 | Newton's laws cover the effects of forces, but not their causes [Newton, by Papineau] |
| 16708 | Newton's forces were accused of being the scholastics' real qualities [Pasnau on Newton] |
| 13153 | I am studying the quantities and mathematics of forces, not their species or qualities [Newton] |
| 12724 | The aim is to discover forces from motions, and use forces to demonstrate other phenomena [Newton] |
| 13593 | Newton showed that falling to earth and orbiting the sun are essentially the same [Newton, by Ellis] |
| 20969 | Early Newtonians could not formulate conservation of energy, having no concept of potential energy [Newton, by Papineau] |
| 17013 | Absolute space is independent, homogeneous and immovable [Newton] |
| 22915 | Newton needs intervals of time, to define velocity and acceleration [Newton, by Le Poidevin] |
| 22893 | Newton thought his laws of motion needed absolute time [Newton, by Bardon] |
| 17012 | Time exists independently, and flows uniformly [Newton] |
| 14012 | Absolute time, from its own nature, flows equably, without relation to anything external [Newton] |
| 22954 | Newtonian mechanics does not distinguish negative from positive values of time [Newton, by Coveney/Highfield] |
| 17015 | If there is no uniform motion, we cannot exactly measure time [Newton] |
| 17025 | If a perfect being does not rule the cosmos, it is not God [Newton] |
| 8491 | The Ontological Argument fallaciously treats existence as a first-level concept [Frege] |
| 17024 | The elegance of the solar system requires a powerful intellect as designer [Newton] |