148 ideas
16281 | Honesty requires philosophical theories we can commit to with our ordinary commonsense [Lewis] |
16288 | Analysis reduces primitives and makes understanding explicit (without adding new knowledge) [Lewis] |
224 | When questions are doubtful we should concentrate not on objects but on ideas of the intellect [Plato] |
232 | Opposites are as unlike as possible [Plato] |
8937 | Plato's 'Parmenides' is the greatest artistic achievement of the ancient dialectic [Hegel on Plato] |
9651 | Verisimilitude might be explained as being close to the possible world where the truth is exact [Lewis] |
10170 | While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price] |
10166 | ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price] |
10175 | Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price] |
15731 | Quantification sometimes commits to 'sets', but sometimes just to pluralities (or 'classes') [Lewis] |
13986 | Plato found antinomies in ideas, Kant in space and time, and Bradley in relations [Plato, by Ryle] |
14150 | Plato's 'Parmenides' is perhaps the best collection of antinomies ever made [Russell on Plato] |
10165 | 'Analysis' is the theory of the real numbers [Reck/Price] |
10174 | Mereological arithmetic needs infinite objects, and function definitions [Reck/Price] |
10164 | Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price] |
10172 | Set-theory gives a unified and an explicit basis for mathematics [Reck/Price] |
10167 | Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price] |
10169 | Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price] |
10179 | There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price] |
10181 | Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price] |
10182 | There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price] |
10168 | Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price] |
10178 | Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price] |
10176 | Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price] |
10177 | Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price] |
10171 | The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price] |
16150 | One is, so numbers exist, so endless numbers exist, and each one must partake of being [Plato] |
10470 | There are only two kinds: sets, and possibilia (actual and possible particulars) [Lewis, by Oliver] |
229 | The one was and is and will be and was becoming and is becoming and will become [Plato] |
21821 | Plato's Parmenides has a three-part theory, of Primal One, a One-Many, and a One-and-Many [Plato, by Plotinus] |
9650 | Supervenience concerns whether things could differ, so it is a modal notion [Lewis] |
221 | Absolute ideas, such as the Good and the Beautiful, cannot be known by us [Plato] |
8909 | Abstractions may well be verbal fictions, in which we ignore some features of an object [Lewis] |
9057 | Vagueness is semantic indecision: we haven't settled quite what our words are meant to express [Lewis] |
9671 | Whether or not France is hexagonal depends on your standards of precision [Lewis] |
15751 | Surely 'slept in by Washington' is a property of some bed? [Lewis] |
15735 | Properties don't have degree; they are determinate, and things have varying relations to them [Lewis] |
9656 | The 'abundant' properties are just any bizarre property you fancy [Lewis] |
15737 | To be a 'property' is to suit a theoretical role [Lewis] |
15742 | A disjunctive property can be unnatural, but intrinsic if its disjuncts are intrinsic [Lewis] |
15741 | All of the natural properties are included among the intrinsic properties [Lewis] |
15398 | Global intrinsic may make necessarily coextensive properties both intrinsic or both extrinsic [Cameron on Lewis] |
15397 | If a global intrinsic never varies between possible duplicates, all necessary properties are intrinsic [Cameron on Lewis] |
15752 | We might try defining the natural properties by a short list of them [Lewis] |
14996 | Natural properties give similarity, joint carving, intrinsicness, specificity, homogeneity... [Lewis] |
15744 | We can't define natural properties by resemblance, if they are used to explain resemblance [Lewis] |
15743 | Defining natural properties by means of laws of nature is potentially circular [Lewis] |
15740 | I don't take 'natural' properties to be fixed by the nature of one possible world [Lewis] |
16262 | Sparse properties rest either on universals, or on tropes, or on primitive naturalness [Lewis, by Maudlin] |
15739 | There is the property of belonging to a set, so abundant properties are as numerous as the sets [Lewis] |
10723 | A property is the set of its actual and possible instances [Lewis, by Oliver] |
15399 | The property of being F is identical with the set of objects, in all possible worlds, which are F [Lewis, by Cameron] |
15732 | Properties don't seem to be sets, because different properties can have the same set [Lewis] |
15733 | Accidentally coextensive properties come apart when we include their possible instances [Lewis] |
15734 | If a property is relative, such as being a father or son, then set membership seems relative too [Lewis] |
9655 | Trilateral and triangular seem to be coextensive sets in all possible worlds [Lewis] |
16290 | I believe in properties, which are sets of possible individuals [Lewis] |
9653 | It would be easiest to take a property as the set of its instances [Lewis] |
9657 | You must accept primitive similarity to like tropes, but tropes give a good account of it [Lewis] |
15749 | Trope theory (unlike universals) needs a primitive notion of being duplicates [Lewis] |
15750 | Tropes need a similarity primitive, so they cannot be used to explain similarity [Lewis] |
15748 | Trope theory needs a primitive notion for what unites some tropes [Lewis] |
15745 | Universals recur, are multiply located, wholly present, make things overlap, and are held in common [Lewis] |
15746 | If particles were just made of universals, similar particles would be the same particle [Lewis] |
223 | If you deny that each thing always stays the same, you destroy the possibility of discussion [Plato] |
227 | You must always mean the same thing when you utter the same name [Plato] |
15747 | Universals aren't parts of things, because that relationship is transitive, and universals need not be [Lewis] |
210 | It would be absurd to think there were abstract Forms for vile things like hair, mud and dirt [Plato] |
16151 | Plato moves from Forms to a theory of genera and principles in his later work [Plato, by Frede,M] |
211 | If admirable things have Forms, maybe everything else does as well [Plato] |
228 | Greatness and smallness must exist, to be opposed to one another, and come into being in things [Plato] |
219 | If absolute ideas existed in us, they would cease to be absolute [Plato] |
220 | The concept of a master includes the concept of a slave [Plato] |
218 | Participation is not by means of similarity, so we are looking for some other method of participation [Plato] |
212 | The whole idea of each Form must be found in each thing which participates in it [Plato] |
213 | Each idea is in all its participants at once, just as daytime is a unity but in many separate places at once [Plato] |
216 | If things are made alike by participating in something, that thing will be the absolute idea [Plato] |
215 | If things partake of ideas, this implies either that everything thinks, or that everything actually is thought [Plato] |
214 | If absolute greatness and great things are seen as the same, another thing appears which makes them seem great [Plato] |
217 | Nothing can be like an absolute idea, because a third idea intervenes to make them alike (leading to a regress) [Plato] |
10173 | A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price] |
15851 | Parts must belong to a created thing with a distinct form [Plato] |
15846 | In Parmenides, if composition is identity, a whole is nothing more than its parts [Plato, by Harte,V] |
15849 | Plato says only a one has parts, and a many does not [Plato, by Harte,V] |
15850 | Anything which has parts must be one thing, and parts are of a one, not of a many [Plato] |
13259 | It seems that the One must be composed of parts, which contradicts its being one [Plato] |
9667 | Mereological composition is unrestricted: any class of things has a mereological sum [Lewis] |
13268 | There are no restrictions on composition, because they would be vague, and composition can't be vague [Lewis, by Sider] |
13793 | An essential property is one possessed by all counterparts [Lewis, by Elder] |
9663 | A thing 'perdures' if it has separate temporal parts, and 'endures' if it is wholly present at different times [Lewis] |
14737 | Properties cannot be relations to times, if there are temporary properties which are intrinsic [Lewis, by Sider] |
9664 | Endurance is the wrong account, because things change intrinsic properties like shape [Lewis] |
9665 | There are three responses to the problem that intrinsic shapes do not endure [Lewis] |
19280 | I can ask questions which create a context in which origin ceases to be essential [Lewis] |
15968 | Identity is simple - absolutely everything is self-identical, and nothing is identical to another thing [Lewis] |
15847 | Two things relate either as same or different, or part of a whole, or the whole of the part [Plato] |
15969 | Two things can never be identical, so there is no problem [Lewis] |
9660 | The impossible can be imagined as long as it is a bit vague [Lewis] |
9669 | There are no free-floating possibilia; they have mates in a world, giving them extrinsic properties [Lewis] |
16132 | On mountains or in worlds, reporting contradictions is contradictory, so no such truths can be reported [Lewis] |
16133 | Possible worlds can contain contradictions if such worlds are seen as fictions [Lewis] |
12255 | For Lewis there is no real possibility, since all possibilities are actual [Oderberg on Lewis] |
9219 | Lewis posits possible worlds just as Quine says that physics needs numbers and sets [Lewis, by Sider] |
16283 | For me, all worlds are equal, with each being actual relative to itself [Lewis] |
15022 | If possible worlds really exist, then they are part of actuality [Sider on Lewis] |
10469 | A world is a maximal mereological sum of spatiotemporally interrelated things [Lewis] |
16441 | Lewis rejects actualism because he identifies properties with sets [Lewis, by Stalnaker] |
16282 | Ersatzers say we have one world, and abstract representations of how it might have been [Lewis] |
16284 | Ersatz worlds represent either through language, or by models, or magically [Lewis] |
16286 | Linguistic possible worlds need a complete supply of unique names for each thing [Lewis] |
16287 | Maximal consistency for a world seems a modal distinction, concerning what could be true together [Lewis] |
9662 | Linguistic possible worlds have problems of inconsistencies, no indiscernibles, and vocabulary [Lewis] |
7690 | If sets exist, then defining worlds as proposition sets implies an odd distinction between existing and actual [Jacquette on Lewis] |
14404 | The counterpart relation is sortal-relative, so objects need not be a certain way [Lewis, by Merricks] |
5441 | Why should statements about what my 'counterpart' could have done interest me? [Mautner on Lewis] |
5440 | A counterpart in a possible world is sufficiently similar, and more similar than anything else [Lewis, by Mautner] |
16291 | In counterpart theory 'Humphrey' doesn't name one being, but a mereological sum of many beings [Lewis] |
11903 | Extreme haecceitists could say I might have been a poached egg, but it is too remote to consider [Lewis, by Mackie,P] |
15129 | Haecceitism implies de re differences but qualitative identity [Lewis] |
9670 | Extreme haecceitism says you might possibly be a poached egg [Lewis] |
16279 | General causal theories of knowledge are refuted by mathematics [Lewis] |
9661 | Induction is just reasonable methods of inferring the unobserved from the observed [Lewis] |
9652 | To just expect unexamined emeralds to be grue would be totally unreasonable [Lewis] |
9658 | An explanation tells us how an event was caused [Lewis] |
16280 | Often explanaton seeks fundamental laws, rather than causal histories [Lewis] |
16274 | If the well-ordering of a pack of cards was by shuffling, the explanation would make it more surprising [Lewis] |
8901 | Abstraction is usually explained either by example, or conflation, or abstraction, or negatively [Lewis] |
8904 | The Way of Abstraction says an incomplete description of a concrete entity is the complete abstraction [Lewis] |
8938 | The Way of Example compares donkeys and numbers, but what is the difference, and what are numbers? [Lewis] |
8903 | Abstracta can be causal: sets can be causes or effects; there can be universal effects; events may be sets [Lewis] |
8902 | If abstractions are non-spatial, then both sets and universals seem to have locations [Lewis] |
8906 | If we can abstract the extrinsic relations and features of objects, abstraction isn't universals or tropes [Lewis] |
8905 | If universals or tropes are parts of things, then abstraction picks out those parts [Lewis] |
8908 | For most sets, the concept of equivalence is too artificial to explain abstraction [Lewis] |
8907 | The abstract direction of a line is the equivalence class of it and all lines parallel to it [Lewis] |
16289 | We can't account for an abstraction as 'from' something if the something doesn't exist [Lewis] |
16278 | A particular functional role is what gives content to a thought [Lewis] |
9654 | A proposition is a set of entire possible worlds which instantiate a particular property [Lewis] |
15736 | A proposition is the property of being a possible world where it holds true [Lewis] |
15738 | Propositions can't have syntactic structure if they are just sets of worlds [Lewis] |
222 | Only a great person can understand the essence of things, and an even greater person can teach it [Plato] |
225 | The unlimited has no shape and is endless [Plato] |
233 | Some things do not partake of the One [Plato] |
231 | Everything partakes of the One in some way [Plato] |
2062 | The only movement possible for the One is in space or in alteration [Plato] |
9659 | Causation is when at the closest world without the cause, there is no effect either [Lewis] |
9666 | It is quite implausible that the future is unreal, as that would terminate everything [Lewis] |
234 | We couldn't discuss the non-existence of the One without knowledge of it [Plato] |