115 ideas
| 6123 | Empirical investigation can't discover if holes exist, or if two things share a colour [Merricks] |
| 16030 | 'Nominal' definitions identify things, but fail to give their essence [Jones,J-E] |
| 8721 | An 'impredicative' definition seems circular, because it uses the term being defined [Friend] |
| 8680 | Classical definitions attempt to refer, but intuitionist/constructivist definitions actually create objects [Friend] |
| 19215 | Arguers often turn the opponent's modus ponens into their own modus tollens [Merricks] |
| 3678 | Reductio ad absurdum proves an idea by showing that its denial produces contradiction [Friend] |
| 8705 | Anti-realists see truth as our servant, and epistemically contrained [Friend] |
| 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] |
| 19205 | 'Snow is white' only contingently expresses the proposition that snow is white [Merricks] |
| 14419 | Deflationism just says there is no property of being truth [Merricks] |
| 8713 | In classical/realist logic the connectives are defined by truth-tables [Friend] |
| 19209 | Simple Quantified Modal Logc doesn't work, because the Converse Barcan is a theorem [Merricks] |
| 19208 | The Converse Barcan implies 'everything exists necessarily' is a consequence of 'necessarily, everything exists' [Merricks] |
| 8708 | Double negation elimination is not valid in intuitionist logic [Friend] |
| 8694 | Free logic was developed for fictional or non-existent objects [Friend] |
| 8665 | A 'proper subset' of A contains only members of A, but not all of them [Friend] |
| 8672 | A 'powerset' is all the subsets of a set [Friend] |
| 8677 | Set theory makes a minimum ontological claim, that the empty set exists [Friend] |
| 8666 | Infinite sets correspond one-to-one with a subset [Friend] |
| 8682 | Major set theories differ in their axioms, and also over the additional axioms of choice and infinity [Friend] |
| 8709 | The law of excluded middle is syntactic; it just says A or not-A, not whether they are true or false [Friend] |
| 8711 | Intuitionists read the universal quantifier as "we have a procedure for checking every..." [Friend] |
| 19207 | Sentence logic maps truth values; predicate logic maps objects and sets [Merricks] |
| 8675 | Paradoxes can be solved by talking more loosely of 'classes' instead of 'sets' [Friend] |
| 8674 | The Burali-Forti paradox asks whether the set of all ordinals is itself an ordinal [Friend] |
| 8667 | The 'integers' are the positive and negative natural numbers, plus zero [Friend] |
| 8668 | The 'rational' numbers are those representable as fractions [Friend] |
| 8670 | A number is 'irrational' if it cannot be represented as a fraction [Friend] |
| 8661 | The natural numbers are primitive, and the ordinals are up one level of abstraction [Friend] |
| 8664 | Cardinal numbers answer 'how many?', with the order being irrelevant [Friend] |
| 8671 | The 'real' numbers (rationals and irrationals combined) is the Continuum, which has no gaps [Friend] |
| 8663 | Raising omega to successive powers of omega reveal an infinity of infinities [Friend] |
| 8662 | The first limit ordinal is omega (greater, but without predecessor), and the second is twice-omega [Friend] |
| 8669 | Between any two rational numbers there is an infinite number of rational numbers [Friend] |
| 8676 | Is mathematics based on sets, types, categories, models or topology? [Friend] |
| 8678 | Most mathematical theories can be translated into the language of set theory [Friend] |
| 8701 | The number 8 in isolation from the other numbers is of no interest [Friend] |
| 8702 | In structuralism the number 8 is not quite the same in different structures, only equivalent [Friend] |
| 8699 | Are structures 'ante rem' (before reality), or are they 'in re' (grounded in physics)? [Friend] |
| 8696 | Structuralist says maths concerns concepts about base objects, not base objects themselves [Friend] |
| 8695 | Structuralism focuses on relations, predicates and functions, with objects being inessential [Friend] |
| 8700 | 'In re' structuralism says that the process of abstraction is pattern-spotting [Friend] |
| 8681 | The big problem for platonists is epistemic: how do we perceive, intuit, know or detect mathematical facts? [Friend] |
| 8712 | Mathematics should be treated as true whenever it is indispensable to our best physical theory [Friend] |
| 8716 | Formalism is unconstrained, so cannot indicate importance, or directions for research [Friend] |
| 8706 | Constructivism rejects too much mathematics [Friend] |
| 8707 | Intuitionists typically retain bivalence but reject the law of excluded middle [Friend] |
| 14393 | The totality state is the most plausible truthmaker for negative existential truths [Merricks] |
| 6143 | Prolonged events don't seem to endure or exist at any particular time [Merricks] |
| 6135 | A crumbling statue can't become vague, because vagueness is incoherent [Merricks] |
| 14413 | Some properties seem to be primitive, but others can be analysed [Merricks] |
| 6145 | Intrinsic properties are those an object still has even if only that object exists [Merricks] |
| 14416 | An object can have a disposition when the revelant conditional is false [Merricks] |
| 6124 | I say that most of the objects of folk ontology do not exist [Merricks] |
| 6134 | Is swimming pool water an object, composed of its mass or parts? [Merricks] |
| 8704 | Structuralists call a mathematical 'object' simply a 'place in a structure' [Friend] |
| 14392 | Fregeans say 'hobbits do not exist' is just 'being a hobbit' is not exemplified [Merricks] |
| 6125 | We can eliminate objects without a commitment to simples [Merricks] |
| 14229 | Merricks agrees that there are no composite objects, but offers a different semantics [Merricks, by Liggins] |
| 6142 | The 'folk' way of carving up the world is not intrinsically better than quite arbitrary ways [Merricks] |
| 14472 | If atoms 'arranged baseballwise' break a window, that analytically entails that a baseball did it [Merricks, by Thomasson] |
| 14469 | Overdetermination: the atoms do all the causing, so the baseball causes no breakage [Merricks] |
| 6137 | Clay does not 'constitute' a statue, as they have different persistence conditions (flaking, squashing) [Merricks] |
| 6127 | 'Unrestricted composition' says any two things can make up a third thing [Merricks] |
| 6131 | Composition as identity is false, as identity is never between a single thing and many things [Merricks] |
| 6132 | Composition as identity is false, as it implies that things never change their parts [Merricks] |
| 6141 | There is no visible difference between statues, and atoms arranged statuewise [Merricks] |
| 6130 | 'Composition' says things are their parts; 'constitution' says a whole substance is an object [Merricks] |
| 6138 | It seems wrong that constitution entails that two objects are wholly co-located [Merricks] |
| 6128 | Objects decompose (it seems) into non-overlapping parts that fill its whole region [Merricks] |
| 14410 | You believe you existed last year, but your segment doesn't, so they have different beliefs [Merricks] |
| 19214 | In twinning, one person has the same origin as another person [Merricks] |
| 6136 | Eliminativism about objects gives the best understanding of the Sorites paradox [Merricks] |
| 14417 | Counterfactuals aren't about actuality, so they lack truthmakers or a supervenience base [Merricks] |
| 6133 | If my counterpart is happy, that is irrelevant to whether I 'could' have been happy [Merricks] |
| 14402 | If 'Fido is possibly black' depends on Fido's counterparts, then it has no actual truthmaker [Merricks] |
| 6150 | The 'warrant' for a belief is what turns a true belief into knowledge [Merricks] |
| 6144 | You hold a child in your arms, so it is not mental substance, or mental state, or software [Merricks] |
| 6140 | Maybe the word 'I' can only refer to persons [Merricks] |
| 6149 | Free will and determinism are incompatible, since determinism destroys human choice [Merricks] |
| 6148 | Human organisms can exercise downward causation [Merricks] |
| 8685 | Studying biology presumes the laws of chemistry, and it could never contradict them [Friend] |
| 6146 | Before Creation it is assumed that God still had many many mental properties [Merricks] |
| 6147 | The hypothesis of solipsism doesn't seem to be made incoherent by the nature of mental properties [Merricks] |
| 8688 | Concepts can be presented extensionally (as objects) or intensionally (as a characterization) [Friend] |
| 19217 | I don't accept that if a proposition is directly about an entity, it has a relation to the entity [Merricks] |
| 19203 | A sentence's truth conditions depend on context [Merricks] |
| 19200 | Propositions are standardly treated as possible worlds, or as structured [Merricks] |
| 19206 | 'Cicero is an orator' represents the same situation as 'Tully is an orator', so they are one proposition [Merricks] |
| 19202 | Propositions are necessary existents which essentially (but inexplicably) represent things [Merricks] |
| 19204 | True propositions existed prior to their being thought, and might never be thought [Merricks] |
| 19210 | The standard view of propositions says they never change their truth-value [Merricks] |
| 19201 | Propositions can be 'about' an entity, but that doesn't make the entity a constituent of it [Merricks] |
| 19211 | Early Russell says a proposition is identical with its truthmaking state of affairs [Merricks] |
| 19212 | Unity of the proposition questions: what unites them? can the same constituents make different ones? [Merricks] |
| 19213 | We want to explain not just what unites the constituents, but what unites them into a proposition [Merricks] |
| 17960 | Eternalism says all times are equally real, and future and past objects and properties are real [Merricks] |
| 17961 | Growing block has a subjective present and a growing edge - but these could come apart [Merricks, by PG] |
| 14411 | Maybe only presentism allows change, by now having a property, and then lacking it [Merricks] |
| 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] |
| 14405 | How can a presentist explain an object's having existed? [Merricks] |