110 ideas
| 1597 | Thales was the first western thinker to believe the arché was intelligible [Roochnik on Thales] |
| 8558 | One system has properties, powers, events, similarity and substance [Shoemaker] |
| 8559 | Analysis aims at internal relationships, not reduction [Shoemaker] |
| 8594 | People have had good reasons for thinking that the circle has been squared [Shoemaker] |
| 10987 | Three traditional names of rules are 'Simplification', 'Addition' and 'Disjunctive Syllogism' [Read] |
| 11004 | Necessity is provability in S4, and true in all worlds in S5 [Read] |
| 11018 | There are fuzzy predicates (and sets), and fuzzy quantifiers and modifiers [Read] |
| 11011 | Same say there are positive, negative and neuter free logics [Read] |
| 11020 | Realisms like the full Comprehension Principle, that all good concepts determine sets [Read] |
| 14187 | If logic is topic-neutral that means it delves into all subjects, rather than having a pure subject matter [Read] |
| 10986 | Not all validity is captured in first-order logic [Read] |
| 10972 | The non-emptiness of the domain is characteristic of classical logic [Read] |
| 11024 | Semantics must precede proof in higher-order logics, since they are incomplete [Read] |
| 10985 | We should exclude second-order logic, precisely because it captures arithmetic [Read] |
| 14188 | Not all arguments are valid because of form; validity is just true premises and false conclusion being impossible [Read] |
| 14182 | If the logic of 'taller of' rests just on meaning, then logic may be the study of merely formal consequence [Read] |
| 14183 | Maybe arguments are only valid when suppressed premises are all stated - but why? [Read] |
| 10970 | A theory of logical consequence is a conceptual analysis, and a set of validity techniques [Read] |
| 10984 | Logical consequence isn't just a matter of form; it depends on connections like round-square [Read] |
| 14184 | In modus ponens the 'if-then' premise contributes nothing if the conclusion follows anyway [Read] |
| 14186 | Logical connectives contain no information, but just record combination relations between facts [Read] |
| 10973 | A theory is logically closed, which means infinite premisses [Read] |
| 11007 | Quantifiers are second-order predicates [Read] |
| 10978 | In second-order logic the higher-order variables range over all the properties of the objects [Read] |
| 10971 | A logical truth is the conclusion of a valid inference with no premisses [Read] |
| 15091 | Restrict 'logical truth' to formal logic, rather than including analytic and metaphysical truths [Shoemaker] |
| 10988 | Any first-order theory of sets is inadequate [Read] |
| 10974 | Compactness is when any consequence of infinite propositions is the consequence of a finite subset [Read] |
| 10975 | Compactness does not deny that an inference can have infinitely many premisses [Read] |
| 10977 | Compactness blocks the proof of 'for every n, A(n)' (as the proof would be infinite) [Read] |
| 10976 | Compactness makes consequence manageable, but restricts expressive power [Read] |
| 11014 | Self-reference paradoxes seem to arise only when falsity is involved [Read] |
| 11025 | Infinite cuts and successors seems to suggest an actual infinity there waiting for us [Read] |
| 10979 | Although second-order arithmetic is incomplete, it can fully model normal arithmetic [Read] |
| 10980 | Second-order arithmetic covers all properties, ensuring categoricity [Read] |
| 10997 | Von Neumann numbers are helpful, but don't correctly describe numbers [Read] |
| 8596 | Inability to measure equality doesn't make all lengths unequal [Shoemaker] |
| 8597 | We couldn't verify the earth's rotation if everyone simultaneously fell asleep [Shoemaker] |
| 11016 | Would a language without vagueness be usable at all? [Read] |
| 11019 | Supervaluations say there is a cut-off somewhere, but at no particular place [Read] |
| 11012 | A 'supervaluation' gives a proposition consistent truth-value for classical assignments [Read] |
| 11013 | Identities and the Indiscernibility of Identicals don't work with supervaluations [Read] |
| 15092 | Formerly I said properties are individuated by essential causal powers and causing instantiation [Shoemaker, by Shoemaker] |
| 15095 | A property's causal features are essential, and only they fix its identity [Shoemaker] |
| 15097 | I claim that a property has its causal features in all possible worlds [Shoemaker] |
| 8543 | Genuine properties are closely related to genuine changes [Shoemaker] |
| 8551 | Properties must be essentially causal if we can know and speak about them [Shoemaker] |
| 8557 | To ascertain genuine properties, examine the object directly [Shoemaker] |
| 15761 | We should abandon the idea that properties are the meanings of predicate expressions [Shoemaker] |
| 15756 | Some truths are not because of a thing's properties, but because of the properties of related things [Shoemaker] |
| 15758 | Things have powers in virtue of (which are entailed by) their properties [Shoemaker] |
| 8547 | One power can come from different properties; a thing's powers come from its properties [Shoemaker] |
| 8549 | Properties are functions producing powers, and powers are functions producing effects [Shoemaker] |
| 15094 | I now deny that properties are cluster of powers, and take causal properties as basic [Shoemaker] |
| 12678 | Shoemaker says all genuine properties are dispositional [Shoemaker, by Ellis] |
| 8545 | A causal theory of properties focuses on change, not (say) on abstract properties of numbers [Shoemaker] |
| 15757 | 'Square', 'round' and 'made of copper' show that not all properties are dispositional [Shoemaker] |
| 15759 | The identity of a property concerns its causal powers [Shoemaker] |
| 15760 | Properties are clusters of conditional powers [Shoemaker] |
| 15762 | Could properties change without the powers changing, or powers change without the properties changing? [Shoemaker] |
| 8552 | If properties are separated from causal powers, this invites total elimination [Shoemaker] |
| 4040 | The notions of property and of causal power are parts of a single system of related concepts [Shoemaker] |
| 15765 | Actually, properties are individuated by causes as well as effects [Shoemaker] |
| 14534 | Shoemaker moved from properties as powers to properties bestowing powers [Shoemaker, by Mumford/Anjum] |
| 8548 | Dispositional predicates ascribe powers, and the rest ascribe properties [Shoemaker] |
| 9485 | Universals concern how things are, and how they could be [Shoemaker, by Bird] |
| 8550 | Triangular and trilateral are coextensive, but different concepts; but powers and properties are the same [Shoemaker] |
| 10995 | A haecceity is a set of individual properties, essential to each thing [Read] |
| 8555 | There is no subset of properties which guarantee a thing's identity [Shoemaker] |
| 11001 | Equating necessity with truth in every possible world is the S5 conception of necessity [Read] |
| 15099 | If something is possible, but not nomologically possible, we need metaphysical possibility [Shoemaker] |
| 8554 | Possible difference across worlds depends on difference across time in the actual world [Shoemaker] |
| 10989 | The standard view of conditionals is that they are truth-functional [Read] |
| 11017 | Some people even claim that conditionals do not express propositions [Read] |
| 10992 | The point of conditionals is to show that one will accept modus ponens [Read] |
| 14185 | Conditionals are just a shorthand for some proof, leaving out the details [Read] |
| 3013 | Nothing is stronger than necessity, which rules everything [Thales, by Diog. Laertius] |
| 15101 | Once you give up necessity as a priori, causal necessity becomes the main type of necessity [Shoemaker] |
| 15764 | 'Conceivable' is either not-provably-false, or compatible with what we know? [Shoemaker] |
| 15098 | Empirical evidence shows that imagining a phenomenon can show it is possible [Shoemaker] |
| 15100 | Imagination reveals conceptual possibility, where descriptions avoid contradiction or incoherence [Shoemaker] |
| 8562 | It is possible to conceive what is not possible [Shoemaker] |
| 10983 | Knowledge of possible worlds is not causal, but is an ontology entailed by semantics [Read] |
| 10982 | How can modal Platonists know the truth of a modal proposition? [Read] |
| 10996 | Actualism is reductionist (to parts of actuality), or moderate realist (accepting real abstractions) [Read] |
| 10981 | A possible world is a determination of the truth-values of all propositions of a domain [Read] |
| 11000 | If worlds are concrete, objects can't be present in more than one, and can only have counterparts [Read] |
| 5691 | The adverbial account of sensation says not 'see a red image' but be 'appeared to redly' [Shoemaker] |
| 8593 | Maybe billions of changeless years have elapsed since my last meal [Shoemaker] |
| 15096 | 'Grue' only has causal features because of its relation to green [Shoemaker] |
| 8556 | Grueness is not, unlike green and blue, associated with causal potential [Shoemaker] |
| 10998 | The mind abstracts ways things might be, which are nonetheless real [Read] |
| 5687 | For true introspection, must we be aware that we are aware of our mental events? [Shoemaker] |
| 5688 | Empirical foundationalism says basic knowledge is self-intimating, and incorrigible or infallible [Shoemaker] |
| 1389 | If memory is the sole criterion of identity, we ought to use it for other people too [Shoemaker] |
| 1390 | Bodily identity is one criterion and memory another, for personal identity [Shoemaker, by PG] |
| 11005 | Negative existentials with compositionality make the whole sentence meaningless [Read] |
| 10966 | A proposition objectifies what a sentence says, as indicative, with secure references [Read] |
| 1494 | Thales said water is the first principle, perhaps from observing that food is moist [Thales, by Aristotle] |
| 8542 | If causality is between events, there must be reference to the properties involved [Shoemaker] |
| 8598 | If things turn red for an hour and then explode, we wouldn't say the redness was the cause [Shoemaker] |
| 15093 | We might say laws are necessary by combining causal properties with Armstrong-Dretske-Tooley laws [Shoemaker] |
| 8560 | If causal laws describe causal potentialities, the same laws govern properties in all possible worlds [Shoemaker] |
| 15763 | If properties are causal, then causal necessity is a species of logical necessity [Shoemaker] |
| 8561 | If a world has different causal laws, it must have different properties [Shoemaker] |
| 8553 | It looks as if the immutability of the powers of a property imply essentiality [Shoemaker] |
| 1713 | Thales must have thought soul causes movement, since he thought magnets have soul [Thales, by Aristotle] |
| 4226 | If three regions 'freeze' every three, four and five years, after sixty years everything stops for a year [Shoemaker, by Lowe] |
| 8595 | If three regions freeze every 3rd, 4th and 5th year, they all freeze together every 60 years [Shoemaker] |
| 1742 | Thales said the gods know our wrong thoughts as well as our evil actions [Thales, by Diog. Laertius] |