71 ideas
| 6123 | Empirical investigation can't discover if holes exist, or if two things share a colour [Merricks] |
| 15413 | With four tense operators, all complex tenses reduce to fourteen basic cases [Burgess] |
| 15415 | The temporal Barcan formulas fix what exists, which seems absurd [Burgess] |
| 15430 | Is classical logic a part of intuitionist logic, or vice versa? [Burgess] |
| 15431 | It is still unsettled whether standard intuitionist logic is complete [Burgess] |
| 15429 | Relevance logic's → is perhaps expressible by 'if A, then B, for that reason' [Burgess] |
| 15404 | Technical people see logic as any formal system that can be studied, not a study of argument validity [Burgess] |
| 15405 | Classical logic neglects the non-mathematical, such as temporality or modality [Burgess] |
| 15427 | The Cut Rule expresses the classical idea that entailment is transitive [Burgess] |
| 15421 | Classical logic neglects counterfactuals, temporality and modality, because maths doesn't use them [Burgess] |
| 15403 | Philosophical logic is a branch of logic, and is now centred in computer science [Burgess] |
| 8729 | Intuitionists deny excluded middle, because it is committed to transcendent truth or objects [Shapiro] |
| 15407 | Formalising arguments favours lots of connectives; proving things favours having very few [Burgess] |
| 15424 | Asserting a disjunction from one disjunct seems odd, but can be sensible, and needed in maths [Burgess] |
| 15409 | All occurrences of variables in atomic formulas are free [Burgess] |
| 15414 | The denotation of a definite description is flexible, rather than rigid [Burgess] |
| 15406 | 'Induction' and 'recursion' on complexity prove by connecting a formula to its atomic components [Burgess] |
| 15426 | We can build one expanding sequence, instead of a chain of deductions [Burgess] |
| 15425 | The sequent calculus makes it possible to have proof without transitivity of entailment [Burgess] |
| 15408 | 'Tautologies' are valid formulas of classical sentential logic - or substitution instances in other logics [Burgess] |
| 15418 | Validity (for truth) and demonstrability (for proof) have correlates in satisfiability and consistency [Burgess] |
| 15411 | We only need to study mathematical models, since all other models are isomorphic to these [Burgess] |
| 15412 | Models leave out meaning, and just focus on truth values [Burgess] |
| 15416 | We aim to get the technical notion of truth in all models matching intuitive truth in all instances [Burgess] |
| 15428 | The Liar seems like a truth-value 'gap', but dialethists see it as a 'glut' [Burgess] |
| 8763 | The number 3 is presumably identical as a natural, an integer, a rational, a real, and complex [Shapiro] |
| 18249 | Cauchy gave a formal definition of a converging sequence. [Shapiro] |
| 8764 | Categories are the best foundation for mathematics [Shapiro] |
| 8762 | Two definitions of 3 in terms of sets disagree over whether 1 is a member of 3 [Shapiro] |
| 8760 | Numbers do not exist independently; the essence of a number is its relations to other numbers [Shapiro] |
| 8761 | A 'system' is related objects; a 'pattern' or 'structure' abstracts the pure relations from them [Shapiro] |
| 8744 | Logicism seems to be a non-starter if (as is widely held) logic has no ontology of its own [Shapiro] |
| 8749 | Term Formalism says mathematics is just about symbols - but real numbers have no names [Shapiro] |
| 8750 | Game Formalism is just a matter of rules, like chess - but then why is it useful in science? [Shapiro] |
| 8752 | Deductivism says mathematics is logical consequences of uninterpreted axioms [Shapiro] |
| 8753 | Critics resent the way intuitionism cripples mathematics, but it allows new important distinctions [Shapiro] |
| 8731 | Conceptualist are just realists or idealist or nominalists, depending on their view of concepts [Shapiro] |
| 8730 | 'Impredicative' definitions refer to the thing being described [Shapiro] |
| 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] |
| 6145 | Intrinsic properties are those an object still has even if only that object exists [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] |
| 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] |
| 6136 | Eliminativism about objects gives the best understanding of the Sorites paradox [Merricks] |
| 15420 | De re modality seems to apply to objects a concept intended for sentences [Burgess] |
| 15419 | General consensus is S5 for logical modality of validity, and S4 for proof [Burgess] |
| 15417 | Logical necessity has two sides - validity and demonstrability - which coincide in classical logic [Burgess] |
| 15422 | Three conditionals theories: Materialism (material conditional), Idealism (true=assertable), Nihilism (no truth) [Burgess] |
| 15423 | It is doubtful whether the negation of a conditional has any clear meaning [Burgess] |
| 6133 | If my counterpart is happy, that is irrelevant to whether I 'could' have been happy [Merricks] |
| 8725 | Rationalism tries to apply mathematical methodology to all of knowledge [Shapiro] |
| 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] |
| 6147 | The hypothesis of solipsism doesn't seem to be made incoherent by the nature of mental properties [Merricks] |
| 6146 | Before Creation it is assumed that God still had many many mental properties [Merricks] |