182 ideas
| 5361 | Philosophers must get used to absurdities [Russell] |
| 5368 | Philosophy verifies that our hierarchy of instinctive beliefs is harmonious and consistent [Russell] |
| 16281 | Honesty requires philosophical theories we can commit to with our ordinary commonsense [Lewis] |
| 5432 | Metaphysics cannot give knowledge of the universe as a whole [Russell] |
| 16288 | Analysis reduces primitives and makes understanding explicit (without adding new knowledge) [Lewis] |
| 5434 | Philosophy is similar to science, and has no special source of wisdom [Russell] |
| 5396 | Three Laws of Thought: identity, contradiction, and excluded middle [Russell] |
| 5405 | The law of contradiction is not a 'law of thought', but a belief about things [Russell] |
| 5420 | Truth is a property of a belief, but dependent on its external relations, not its internal qualities [Russell] |
| 5419 | Truth and falsehood are properties of beliefs and statements [Russell] |
| 9651 | Verisimilitude might be explained as being close to the possible world where the truth is exact [Lewis] |
| 5417 | A good theory of truth must make falsehood possible [Russell] |
| 7395 | Truth as congruence may work for complex beliefs, but not for simple beliefs about existence [Joslin on Russell] |
| 5428 | Beliefs are true if they have corresponding facts, and false if they don't [Russell] |
| 5421 | The coherence theory says falsehood is failure to cohere, and truth is fitting into a complete system of Truth [Russell] |
| 5422 | More than one coherent body of beliefs seems possible [Russell] |
| 5423 | If we suspend the law of contradiction, nothing will appear to be incoherent [Russell] |
| 5424 | Coherence is not the meaning of truth, but an important test for truth [Russell] |
| 5401 | The mortality of Socrates is more certain from induction than it is from deduction [Russell] |
| 5395 | Demonstration always relies on the rule that anything implied by a truth is true [Russell] |
| 5386 | Proper names are really descriptions, and can be replaced by a description in a person's mind [Russell] |
| 5385 | The phrase 'a so-and-so' is an 'ambiguous' description'; 'the so-and-so' (singular) is a 'definite' description [Russell] |
| 15731 | Quantification sometimes commits to 'sets', but sometimes just to pluralities (or 'classes') [Lewis] |
| 5399 | Maths is not known by induction, because further instances are not needed to support it [Russell] |
| 10470 | There are only two kinds: sets, and possibilia (actual and possible particulars) [Lewis, by Oliver] |
| 9650 | Supervenience concerns whether things could differ, so it is a modal notion [Lewis] |
| 5370 | Space is neutral between touch and sight, so it cannot really be either of them [Russell] |
| 8909 | Abstractions may well be verbal fictions, in which we ignore some features of an object [Lewis] |
| 5418 | In a world of mere matter there might be 'facts', but no truths [Russell] |
| 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] |
| 5371 | Because we depend on correspondence, we know relations better than we know the items that relate [Russell] |
| 5407 | That Edinburgh is north of London is a non-mental fact, so relations are independent universals [Russell] |
| 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] |
| 15397 | If a global intrinsic never varies between possible duplicates, all necessary properties are intrinsic [Cameron on Lewis] |
| 15398 | Global intrinsic may make necessarily coextensive properties both intrinsic or both extrinsic [Cameron on Lewis] |
| 15741 | All of the natural properties are included among the intrinsic properties [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] |
| 15750 | Tropes need a similarity primitive, so they cannot be used to explain similarity [Lewis] |
| 15749 | Trope theory (unlike universals) needs a primitive notion of being duplicates [Lewis] |
| 15748 | Trope theory needs a primitive notion for what unites some tropes [Lewis] |
| 5383 | Every complete sentence must contain at least one word (a verb) which stands for a universal [Russell] |
| 4428 | Propositions express relations (prepositions and verbs) as well as properties (nouns and adjectives) [Russell] |
| 5406 | Confused views of reality result from thinking that only nouns and adjectives represent universals [Russell] |
| 4479 | All universals are like the relation "is north of", in having no physical location at all [Russell, by Loux] |
| 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] |
| 4427 | Every sentence contains at least one word denoting a universal, so we need universals to know truth [Russell] |
| 4030 | Russell claims that universals are needed to explain a priori knowledge (as their relations) [Russell, by Mellor/Oliver] |
| 15747 | Universals aren't parts of things, because that relationship is transitive, and universals need not be [Lewis] |
| 5409 | Normal existence is in time, so we must say that universals 'subsist' [Russell] |
| 5408 | If we identify whiteness with a thought, we can never think of it twice; whiteness is the object of a thought [Russell] |
| 4441 | 'Resemblance Nominalism' won't work, because the theory treats resemblance itself as a universal [Russell] |
| 4429 | If we consider whiteness to be merely a mental 'idea', we rob it of its universality [Russell] |
| 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] |
| 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] |
| 5400 | In any possible world we feel that two and two would be four [Russell] |
| 9669 | There are no free-floating possibilia; they have mates in a world, giving them extrinsic properties [Lewis] |
| 16133 | Possible worlds can contain contradictions if such worlds are seen as fictions [Lewis] |
| 16132 | On mountains or in worlds, reporting contradictions is contradictory, so no such truths can be reported [Lewis] |
| 16283 | For me, all worlds are equal, with each being actual relative to itself [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] |
| 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] |
| 5440 | A counterpart in a possible world is sufficiently similar, and more similar than anything else [Lewis, by Mautner] |
| 5441 | Why should statements about what my 'counterpart' could have done interest me? [Mautner on Lewis] |
| 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] |
| 5431 | Knowledge cannot be precisely defined, as it merges into 'probable opinion' [Russell] |
| 5426 | Belief relates a mind to several things other than itself [Russell] |
| 5366 | We have an 'instinctive' belief in the external world, prior to all reflection [Russell] |
| 5359 | Descartes showed that subjective things are the most certain [Russell] |
| 5377 | 'Acquaintance' is direct awareness, without inferences or judgements [Russell] |
| 6510 | Russell (1912) said phenomena only resemble reality in abstract structure [Russell, by Robinson,H] |
| 5372 | There is no reason to think that objects have colours [Russell] |
| 5373 | 'Idealism' says that everything which exists is in some sense mental [Russell] |
| 5362 | It is not illogical to think that only myself and my mental events exist [Russell] |
| 5412 | Some propositions are self-evident, but their implications may also be self-evident [Russell] |
| 5413 | Particular instances are more clearly self-evident than any general principles [Russell] |
| 5415 | As shown by memory, self-evidence comes in degrees [Russell] |
| 5416 | If self-evidence has degrees, we should accept the more self-evident as correct [Russell] |
| 5397 | The rationalists were right, because we know logical principles without experience [Russell] |
| 4430 | All a priori knowledge deals with the relations of universals [Russell] |
| 5411 | We can know some general propositions by universals, when no instance can be given [Russell] |
| 6514 | Russell's representationalism says primary qualities only show the structure of reality [Russell, by Robinson,H] |
| 6415 | After 1912, Russell said sense-data are last in analysis, not first in experience [Russell, by Grayling] |
| 5358 | 'Sense-data' are what are immediately known in sensation, such as colours or roughnesses [Russell] |
| 7290 | If Russell rejects innate ideas and direct a priori knowledge, he is left with a tabula rasa [Russell, by Thompson] |
| 5357 | It is natural to begin from experience, and presumably that is the basis of knowledge [Russell] |
| 5382 | We are acquainted with outer and inner sensation, memory, Self, and universals [Russell, by PG] |
| 5389 | Knowledge by descriptions enables us to transcend private experience [Russell] |
| 5376 | I can know the existence of something with which nobody is acquainted [Russell] |
| 5414 | Images are not memory, because they are present, and memories are of the past [Russell] |
| 5430 | A true belief is not knowledge if it is reached by bad reasoning [Russell] |
| 5429 | True belief is not knowledge when it is deduced from false belief [Russell] |
| 5378 | All knowledge (of things and of truths) rests on the foundations of acquaintance [Russell] |
| 16279 | General causal theories of knowledge are refuted by mathematics [Lewis] |
| 5365 | Dreams can be explained fairly scientifically if we assume a physical world [Russell] |
| 5391 | Science aims to find uniformities to which (within the limits of experience) there are no exceptions [Russell] |
| 9661 | Induction is just reasonable methods of inferring the unobserved from the observed [Lewis] |
| 5394 | We can't prove induction from experience without begging the question [Russell] |
| 5390 | Chickens are not very good at induction, and are surprised when their feeder wrings their neck [Russell] |
| 5392 | It doesn't follow that because the future has always resembled the past, that it always will [Russell] |
| 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] |
| 5363 | If the cat reappears in a new position, presumably it has passed through the intermediate positions [Russell] |
| 5367 | Belief in real objects makes our account of experience simpler and more systematic [Russell] |
| 5364 | It is hard not to believe that speaking humans are expressing thoughts, just as we do ourselves [Russell] |
| 5379 | If we didn't know our own minds by introspection, we couldn't know that other people have minds [Russell] |
| 5410 | I learn the universal 'resemblance' by seeing two shades of green, and their contrast with red [Russell] |
| 5381 | In seeing the sun, we are acquainted with our self, but not as a permanent person [Russell] |
| 5380 | In perceiving the sun, I am aware of sun sense-data, and of the perceiver of the data [Russell] |
| 5369 | It is rational to believe in reality, despite the lack of demonstrative reasons for it [Russell] |
| 5375 | Knowledge of truths applies to judgements; knowledge by acquaintance applies to sensations and things [Russell] |
| 21711 | Russell's 'multiple relations' theory says beliefs attach to ingredients, not to propositions [Russell, by Linsky,B] |
| 5427 | Truth is when a mental state corresponds to a complex unity of external constituents [Russell] |
| 5425 | In order to explain falsehood, a belief must involve several terms, not two [Russell] |
| 5384 | A universal of which we are aware is called a 'concept' [Russell] |
| 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] |
| 8905 | If universals or tropes are parts of things, then abstraction picks out those parts [Lewis] |
| 8906 | If we can abstract the extrinsic relations and features of objects, abstraction isn't universals or tropes [Lewis] |
| 8907 | The abstract direction of a line is the equivalence class of it and all lines parallel to it [Lewis] |
| 8908 | For most sets, the concept of equivalence is too artificial to explain abstraction [Lewis] |
| 16289 | We can't account for an abstraction as 'from' something if the something doesn't exist [Lewis] |
| 13468 | Russell started philosophy of language, by declaring some plausible sentences to be meaningless [Russell, by Hart,WD] |
| 5388 | Every understood proposition is composed of constituents with which we are acquainted [Russell] |
| 16278 | A particular functional role is what gives content to a thought [Lewis] |
| 5387 | It is pure chance which descriptions in a person's mind make a name apply to an individual [Russell] |
| 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] |
| 21724 | The main aim of the multiple relations theory of judgement was to dispense with propositions [Russell, by Linsky,B] |
| 20344 | Music is not an expressive art, because it expresses no familiar emotions [Hanslick, by Wollheim] |
| 5398 | Judgements of usefulness depend on judgements of value [Russell] |
| 9659 | Causation is when at the closest world without the cause, there is no effect either [Lewis] |
| 5393 | We can't know that our laws are exceptionless, or even that there are any laws [Russell] |
| 9666 | It is quite implausible that the future is unreal, as that would terminate everything [Lewis] |