134 ideas
19275 | You cannot understand what exists without understanding possibility and necessity [Hale] |
1887 | You cannot divide anything into many parts, because after the first division you are no longer dividing the original [Sext.Empiricus] |
22764 | Ordinary speech is not exact about what is true; we say we are digging a well before the well exists [Sext.Empiricus] |
10308 | Questions about objects are questions about certain non-vacuous singular terms [Hale] |
22752 | Reasoning is impossible without a preconception [Sext.Empiricus] |
19291 | A canonical defintion specifies the type of thing, and what distinguish this specimen [Hale] |
10314 | An expression is a genuine singular term if it resists elimination by paraphrase [Hale] |
1885 | Proof moves from agreed premises to a non-evident inference [Sext.Empiricus] |
6021 | It is only when we say a proposition that we speak truly or falsely [Sext.Empiricus] |
19297 | The two Barcan principles are easily proved in fairly basic modal logic [Hale] |
19301 | With a negative free logic, we can dispense with the Barcan formulae [Hale] |
19296 | If second-order variables range over sets, those are just objects; properties and relations aren't sets [Hale] |
12196 | A valid hypothetical syllogism is 'that which does not begin with a truth and end with a falsehood' [Sext.Empiricus] |
19289 | Maybe conventionalism applies to meaning, but not to the truth of propositions expressed [Hale] |
6020 | 'Man is a rational mortal animal' is equivalent to 'if something is a man, that thing is a rational mortal animal' [Sext.Empiricus] |
10316 | We should decide whether singular terms are genuine by their usage [Hale] |
10312 | Often the same singular term does not ensure reliable inference [Hale] |
10313 | Plenty of clear examples have singular terms with no ontological commitment [Hale] |
10322 | If singular terms can't be language-neutral, then we face a relativity about their objects [Hale] |
19298 | Unlike axiom proofs, natural deduction proofs needn't focus on logical truths and theorems [Hale] |
1902 | Since Socrates either died when he was alive (a contradiction) or died when he was dead (meaningless), he didn't die [Sext.Empiricus] |
10632 | The real numbers may be introduced by abstraction as ratios of quantities [Hale, by Hale/Wright] |
19295 | Add Hume's principle to logic, to get numbers; arithmetic truths rest on the nature of the numbers [Hale] |
19281 | Interesting supervenience must characterise the base quite differently from what supervenes on it [Hale] |
10512 | The abstract/concrete distinction is based on what is perceivable, causal and located [Hale] |
10517 | Colours and points seem to be both concrete and abstract [Hale] |
10519 | The abstract/concrete distinction is in the relations in the identity-criteria of object-names [Hale] |
10520 | Token-letters and token-words are concrete objects, type-letters and type-words abstract [Hale] |
10524 | There is a hierarchy of abstraction, based on steps taken by equivalence relations [Hale] |
19278 | There is no gap between a fact that p, and it is true that p; so we only have the truth-condtions for p [Hale] |
10318 | Realists take universals to be the referrents of both adjectives and of nouns [Hale] |
10521 | If F can't have location, there is no problem of things having F in different locations [Hale] |
10511 | It is doubtful if one entity, a universal, can be picked out by both predicates and abstract nouns [Hale] |
10310 | Objections to Frege: abstracta are unknowable, non-independent, unstatable, unindividuated [Hale] |
10518 | Shapes and directions are of something, but games and musical compositions are not [Hale] |
10513 | Many abstract objects, such as chess, seem non-spatial, but are not atemporal [Hale] |
10514 | If the mental is non-spatial but temporal, then it must be classified as abstract [Hale] |
10523 | Being abstract is based on a relation between things which are spatially separated [Hale] |
10307 | The modern Fregean use of the term 'object' is much broader than the ordinary usage [Hale] |
10315 | We can't believe in a 'whereabouts' because we ask 'what kind of object is it?' [Hale] |
19302 | If a chair could be made of slightly different material, that could lead to big changes [Hale] |
22744 | Parts are not parts if their whole is nothing more than the parts [Sext.Empiricus] |
22762 | Some properties are inseparable from a thing, such as the length, breadth and depth of a body [Sext.Empiricus] |
10522 | The relations featured in criteria of identity are always equivalence relations [Hale] |
10321 | We sometimes apply identity without having a real criterion [Hale] |
15086 | Absolute necessity might be achievable either logically or metaphysically [Hale] |
19290 | Absolute necessities are necessarily necessary [Hale] |
8261 | Maybe not-p is logically possible, but p is metaphysically necessary, so the latter is not absolute [Hale] |
15081 | A strong necessity entails a weaker one, but not conversely; possibilities go the other way [Hale] |
15080 | 'Relative' necessity is just a logical consequence of some statements ('strong' if they are all true) [Hale] |
19286 | 'Absolute necessity' is when there is no restriction on the things which necessitate p [Hale] |
19288 | Logical and metaphysical necessities differ in their vocabulary, and their underlying entities [Hale] |
15082 | Metaphysical necessity says there is no possibility of falsehood [Hale] |
15085 | 'Broadly' logical necessities are derived (in a structure) entirely from the concepts [Hale] |
15088 | Logical necessities are true in virtue of the nature of all logical concepts [Hale] |
19285 | Logical necessity is something which is true, no matter what else is the case [Hale] |
19287 | Maybe each type of logic has its own necessity, gradually becoming broader [Hale] |
12432 | Explanation of necessity must rest on something necessary or something contingent [Hale] |
12434 | Why is this necessary, and what is necessity in general; why is this necessary truth true, and why necessary? [Hale] |
12435 | The explanation of a necessity can be by a truth (which may only happen to be a necessary truth) [Hale] |
19282 | It seems that we cannot show that modal facts depend on non-modal facts [Hale] |
12433 | If necessity rests on linguistic conventions, those are contingent, so there is no necessity [Hale] |
15087 | Conceptual necessities are made true by all concepts [Hale] |
12436 | Concept-identities explain how we know necessities, not why they are necessary [Hale] |
19276 | The big challenge for essentialist views of modality is things having necessary existence [Hale] |
19293 | Essentialism doesn't explain necessity reductively; it explains all necessities in terms of a few basic natures [Hale] |
19294 | If necessity derives from essences, how do we explain the necessary existence of essences? [Hale] |
19279 | What are these worlds, that being true in all of them makes something necessary? [Hale] |
19299 | Possible worlds make every proposition true or false, which endorses classical logic [Hale] |
1889 | If an argument has an absurd conclusion, we should not assent to the absurdity, but avoid the absurd argument [Sext.Empiricus] |
1871 | Whether honey is essentially sweet may be doubted, as it is a matter of judgement rather than appearance [Sext.Empiricus] |
1883 | How can the intellect know if sensation is reliable if it doesn't directly see external objects? [Sext.Empiricus] |
22748 | Some say motion is perceived by sense, but others say it is by intellect [Sext.Empiricus] |
1890 | We distinguish ambiguities by seeing what is useful [Sext.Empiricus] |
22759 | Fools, infants and madmen may speak truly, but do not know [Sext.Empiricus] |
20795 | Some things are their own criterion, such as straightness, a set of scales, or light [Sext.Empiricus] |
22760 | Madmen are reliable reporters of what appears to them [Sext.Empiricus] |
1870 | The basis of scepticism is the claim that every proposition has an equal opposing proposition [Sext.Empiricus] |
1882 | The necks of doves appear different in colour depending on the angle of viewing [Sext.Empiricus] |
1881 | The same oar seems bent in water and straight when out of it [Sext.Empiricus] |
1872 | The same tower appears round from a distance, but square close at hand [Sext.Empiricus] |
1873 | If we press the side of an eyeball, objects appear a different shape [Sext.Empiricus] |
20794 | How can sceptics show there is no criterion? Weak without, contradiction with [Sext.Empiricus] |
1874 | How can we judge between our impressions and those of other animals, when we ourselves are involved? [Sext.Empiricus] |
1878 | Water that seems lukewarm can seem very hot on inflamed skin [Sext.Empiricus] |
1880 | Some actions seem shameful when sober but not when drunk [Sext.Empiricus] |
1877 | If we had no hearing or sight, we would assume no sound or sight exists, so there may be unsensed qualities [Sext.Empiricus] |
1879 | Sickness is perfectly natural to the sick, so their natural perceptions should carry some weight [Sext.Empiricus] |
1876 | If we enjoy different things, presumably we receive different impressions [Sext.Empiricus] |
1910 | With us it is shameful for men to wear earrings, but among Syrians it is considered noble [Sext.Empiricus] |
1911 | Even if all known nations agree on a practice, there may be unknown nations which disagree [Sext.Empiricus] |
6026 | How can you investigate without some preconception of your object? [Sext.Empiricus] |
1886 | If you don't view every particular, you may miss the one which disproves your universal induction [Sext.Empiricus] |
22746 | If we try to conceive of a line with no breadth, it ceases to exist, and so has no length [Sext.Empiricus] |
22741 | The incorporeal is not in the nature of body, and so could not emerge from it [Sext.Empiricus] |
1884 | If we utter three steps of a logical argument, they never exist together [Sext.Empiricus] |
19300 | The molecules may explain the water, but they are not what 'water' means [Hale] |
22763 | We can only dream of a winged man if we have experienced men and some winged thing [Sext.Empiricus] |
22754 | Saying the good is useful or choiceworth or happiness-creating is not the good, but a feature of it [Sext.Empiricus] |
22755 | Like a warming fire, what is good by nature should be good for everyone [Sext.Empiricus] |
22756 | If a desire is itself desirable, then we shouldn't desire it, as achieving it destroys it [Sext.Empiricus] |
6032 | Right actions, once done, are those with a reasonable justification [Sext.Empiricus] |
20239 | Unlike us, the early Greeks thought envy was a good thing, and hope a bad thing [Hesiod, by Nietzsche] |
1517 | The tektraktys (1+2+3+4=10) is the 'fount of ever-flowing nature' [Sext.Empiricus] |
1894 | Some say that causes are physical, some say not [Sext.Empiricus] |
1897 | Knowing an effect results from a cause means knowing that the cause belongs with the effect, which is circular [Sext.Empiricus] |
1898 | Cause can't exist before effect, or exist at the same time, so it doesn't exist [Sext.Empiricus] |
1896 | If there were no causes then everything would have been randomly produced by everything [Sext.Empiricus] |
1895 | Causes are either equal to the effect, or they link equally with other causes, or they contribute slightly [Sext.Empiricus] |
1900 | If time and place are infinitely divided, it becomes impossible for movement ever to begin [Sext.Empiricus] |
1899 | Does the original self-mover push itself from behind, or pull itself from in front? [Sext.Empiricus] |
1901 | If all atoms, times and places are the same, everything should move with equal velocity [Sext.Empiricus] |
22747 | A man walking backwards on a forwards-moving ship is moving in a fixed place [Sext.Empiricus] |
1903 | If motion and rest are abolished, so is time [Sext.Empiricus] |
1904 | Time must be unlimited, but past and present can't be non-existent, and can't be now, so time does not exist [Sext.Empiricus] |
22749 | Time doesn't end with the Universe, because tensed statements about destruction remain true [Sext.Empiricus] |
22750 | Time is divisible, into past, present and future [Sext.Empiricus] |
1905 | How can time be divisible if we can't compare one length of time with another? [Sext.Empiricus] |
22742 | Socrates either dies when he exists (before his death) or when he doesn't (after his death) [Sext.Empiricus] |
22751 | If the present is just the limit of the past or the future, it can't exist because they don't exist [Sext.Empiricus] |
22730 | All men agree that God is blessed, imperishable, happy and good [Sext.Empiricus] |
1891 | How can we agree on the concept of God, unless we agree on his substance or form or place? [Sext.Empiricus] |
22739 | God must suffer to understand suffering [Sext.Empiricus] |
22738 | The Divine must lack the virtues of continence and fortitude, because they are not needed [Sext.Empiricus] |
22734 | God is defended by agreement, order, absurdity of denying God, and refutations [Sext.Empiricus] |
22736 | God's sensations imply change, and hence perishing, which is absurd, so there is no such God [Sext.Empiricus] |
22740 | God without virtue is absurd, but God's virtues will be better than God [Sext.Empiricus] |
1892 | The existence of God can't be self-evident or everyone would have agreed on it, so it needs demonstration [Sext.Empiricus] |
22735 | The original substance lacked motion or shape, and was given these by a cause [Sext.Empiricus] |
22732 | The perfections of God were extrapolations from mankind [Sext.Empiricus] |
22728 | Gods were invented as watchers of people's secret actions [Sext.Empiricus] |
22737 | An incorporeal God could do nothing, and a bodily god would perish, so there is no God [Sext.Empiricus] |
22731 | It is mad to think that what is useful to us, like lakes and rivers, are gods [Sext.Empiricus] |
1893 | If God foresaw evil he would presumably prevent it, and if he only foresees some things, why those things? [Sext.Empiricus] |