48 ideas
14415 | A ground must be about its truth, and not just necessitate it [Merricks] |
14408 | Truthmaker needs truths to be 'about' something, and that is often unclear [Merricks] |
14395 | If a ball changes from red to white, Truthmaker says some thing must make the change true [Merricks] |
14398 | Truthmaker says if an entity is removed, some nonexistence truthmaker must replace it [Merricks] |
14403 | If Truthmaker says each truth is made by the existence of something, the theory had de re modality at is core [Merricks] |
14397 | Truthmaker demands not just a predication, but an existing state of affairs with essential ingredients [Merricks] |
14396 | If 'truth supervenes on being', worlds with the same entities, properties and relations have the same truths [Merricks] |
14400 | If truth supervenes on being, that won't explain why truth depends on being [Merricks] |
14394 | It is implausible that claims about non-existence are about existing things [Merricks] |
14390 | Truthmaker isn't the correspondence theory, because it offers no analysis of truth [Merricks] |
14412 | Speculations about non-existent things are not about existent things, so Truthmaker is false [Merricks] |
14414 | I am a truthmaker for 'that a human exists', but is it about me? [Merricks] |
14418 | Being true is not a relation, it is a primitive monadic property [Merricks] |
14391 | If the correspondence theory is right, then necessary truths must correspond to something [Merricks] |
14419 | Deflationism just says there is no property of being truth [Merricks] |
13520 | A 'tautology' must include connectives [Wolf,RS] |
13524 | Deduction Theorem: T∪{P}|-Q, then T|-(P→Q), which justifies Conditional Proof [Wolf,RS] |
13522 | Universal Generalization: If we prove P(x) with no special assumptions, we can conclude ∀xP(x) [Wolf,RS] |
13521 | Universal Specification: ∀xP(x) implies P(t). True for all? Then true for an instance [Wolf,RS] |
13523 | Existential Generalization (or 'proof by example'): if we can say P(t), then we can say something is P [Wolf,RS] |
13529 | Empty Set: ∃x∀y ¬(y∈x). The unique empty set exists [Wolf,RS] |
13526 | Comprehension Axiom: if a collection is clearly specified, it is a set [Wolf,RS] |
13534 | In first-order logic syntactic and semantic consequence (|- and |=) nicely coincide [Wolf,RS] |
13535 | First-order logic is weakly complete (valid sentences are provable); we can't prove every sentence or its negation [Wolf,RS] |
13531 | Model theory reveals the structures of mathematics [Wolf,RS] |
13532 | Model theory 'structures' have a 'universe', some 'relations', some 'functions', and some 'constants' [Wolf,RS] |
13519 | Model theory uses sets to show that mathematical deduction fits mathematical truth [Wolf,RS] |
13533 | First-order model theory rests on completeness, compactness, and the Löwenheim-Skolem-Tarski theorem [Wolf,RS] |
13537 | An 'isomorphism' is a bijection that preserves all structural components [Wolf,RS] |
13539 | The LST Theorem is a serious limitation of first-order logic [Wolf,RS] |
13538 | If a theory is complete, only a more powerful language can strengthen it [Wolf,RS] |
13525 | Most deductive logic (unlike ordinary reasoning) is 'monotonic' - we don't retract after new givens [Wolf,RS] |
13530 | An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS] |
13518 | Modern mathematics has unified all of its objects within set theory [Wolf,RS] |
14393 | The totality state is the most plausible truthmaker for negative existential truths [Merricks] |
14413 | Some properties seem to be primitive, but others can be analysed [Merricks] |
14416 | An object can have a disposition when the revelant conditional is false [Merricks] |
14392 | Fregeans say 'hobbits do not exist' is just 'being a hobbit' is not exemplified [Merricks] |
14410 | You believe you existed last year, but your segment doesn't, so they have different beliefs [Merricks] |
14417 | Counterfactuals aren't about actuality, so they lack truthmakers or a supervenience base [Merricks] |
14402 | If 'Fido is possibly black' depends on Fido's counterparts, then it has no actual truthmaker [Merricks] |
5049 | Intelligent pleasure is the perception of beauty, order and perfection [Leibniz] |
14406 | Presentists say that things have existed and will exist, not that they are instantaneous [Merricks] |
14407 | Presentist should deny there is a present time, and just say that things 'exist' [Merricks] |
14411 | Maybe only presentism allows change, by now having a property, and then lacking it [Merricks] |
14405 | How can a presentist explain an object's having existed? [Merricks] |
5048 | Perfection is simply quantity of reality [Leibniz] |
5050 | Evil serves a greater good, and pain is necessary for higher pleasure [Leibniz] |