201 ideas
| 16281 | Honesty requires philosophical theories we can commit to with our ordinary commonsense [Lewis] |
| 12997 | Analysis is the art of finding the middle term [Leibniz] |
| 16288 | Analysis reduces primitives and makes understanding explicit (without adding new knowledge) [Lewis] |
| 13009 | A reason is a known truth which leads to assent to some further truth [Leibniz] |
| 12963 | Opposing reason is opposing truth, since reason is a chain of truths [Leibniz] |
| 19360 | General principles, even if unconscious, are indispensable for thinking [Leibniz] |
| 12983 | A nominal definition is of the qualities, but the real definition is of the essential inner structure [Leibniz] |
| 12982 | One essence can be expressed by several definitions [Leibniz] |
| 12976 | If our ideas of a thing are imperfect, the thing can have several unconnected definitions [Leibniz] |
| 12984 | Real definitions, unlike nominal definitions, display possibilities [Leibniz] |
| 12980 | Genus and differentia might be swapped, and 'rational animal' become 'animable rational' [Leibniz] |
| 9651 | Verisimilitude might be explained as being close to the possible world where the truth is exact [Lewis] |
| 13000 | Truth is correspondence between mental propositions and what they are about [Leibniz] |
| 12992 | Logic teaches us how to order and connect our thoughts [Leibniz] |
| 10056 | At bottom eternal truths are all conditional [Leibniz] |
| 12974 | People who can't apply names usually don't understand the thing to which it applies [Leibniz] |
| 15731 | Quantification sometimes commits to 'sets', but sometimes just to pluralities (or 'classes') [Lewis] |
| 13002 | It is always good to reduce the number of axioms [Leibniz] |
| 13008 | Geometry, unlike sensation, lets us glimpse eternal truths and their necessity [Leibniz] |
| 12956 | Only whole numbers are multitudes of units [Leibniz] |
| 12937 | We shouldn't just accept Euclid's axioms, but try to demonstrate them [Leibniz] |
| 10470 | There are only two kinds: sets, and possibilia (actual and possible particulars) [Lewis, by Oliver] |
| 12932 | The idea of being must come from our own existence [Leibniz] |
| 9650 | Supervenience concerns whether things could differ, so it is a modal notion [Lewis] |
| 12966 | Objects of ideas can be divided into abstract and concrete, and then further subdivided [Leibniz] |
| 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] |
| 12993 | Have five categories - substance, quantity, quality, action/passion, relation - and their combinations [Leibniz] |
| 12989 | Our true divisions of nature match reality, but are probably incomplete [Leibniz] |
| 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] |
| 12959 | We discern active power from our minds, so mind must be involved in all active powers [Leibniz] |
| 12967 | I use the word 'entelechy' for a power, to include endeavour, as well as mere aptitude [Leibniz] |
| 12965 | All occurrence in the depth of a substance is spontaneous 'action' [Leibniz] |
| 12999 | Substances are primary powers; their ways of being are the derivative powers [Leibniz] |
| 5056 | Material or immaterial substances cannot be conceived without their essential activity [Leibniz] |
| 12969 | The active powers which are not essential to the substance are the 'real qualities' [Leibniz] |
| 12941 | There cannot be power without action; the power is a disposition to act [Leibniz] |
| 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] |
| 15747 | Universals aren't parts of things, because that relationship is transitive, and universals need not be [Lewis] |
| 12990 | Real (non-logical) abstract terms are either essences or accidents [Leibniz] |
| 12939 | Wholly uniform things like space and numbers are mere abstractions [Leibniz] |
| 12979 | The only way we can determine individuals is by keeping hold of them [Leibniz] |
| 12971 | If two individuals could be indistinguishable, there could be no principle of individuation [Leibniz] |
| 13098 | We use things to distinguish places and times, not vice versa [Leibniz] |
| 13075 | No two things are quite the same, so there must be an internal principle of distinction [Leibniz] |
| 12953 | Fluidity is basic, and we divide into bodies according to our needs [Leibniz] |
| 12943 | Individuality is in the bond substance gives between past and future [Leibniz] |
| 11855 | Substances cannot be bare, but have activity as their essence [Leibniz] |
| 12970 | We can imagine two bodies interpenetrating, as two rays of light seem to [Leibniz] |
| 12986 | The essence of baldness is vague and imperfect [Leibniz] |
| 12968 | A 'substratum' is just a metaphor for whatever supports several predicates [Leibniz] |
| 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] |
| 12931 | Particular truths are just instances of general truths [Leibniz] |
| 12811 | We can't know individuals, or determine their exact individuality [Leibniz] |
| 12981 | Essence is just the possibility of a thing [Leibniz] |
| 13793 | An essential property is one possessed by all counterparts [Lewis, by Elder] |
| 5057 | If you fully understand a subject and its qualities, you see how the second derive from the first [Leibniz] |
| 12987 | For some sorts, a member of it is necessarily a member [Leibniz] |
| 12884 | The same whole ceases to exist if a part is lost [Leibniz] |
| 12975 | We have a distinct idea of gold, to define it, but not a perfect idea, to understand it [Leibniz] |
| 12805 | If two people apply a single term to different resemblances, they refer to two different things [Leibniz] |
| 12806 | Locke needs many instances to show a natural kind, but why not a single instance? [Leibniz, by Jolley] |
| 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] |
| 12972 | Bodies, like Theseus's ship, are only the same in appearance, and never strictly the same [Leibniz] |
| 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] |
| 5055 | No two things are totally identical [Leibniz] |
| 12978 | A perfect idea of an object shows that the object is possible [Leibniz] |
| 17079 | Proofs of necessity come from the understanding, where they have their source [Leibniz] |
| 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] |
| 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] |
| 12998 | Understanding grasps the agreements and disagreements of ideas [Leibniz] |
| 12960 | We understand things when they are distinct, and we can derive necessities from them [Leibniz] |
| 13006 | Certainty is where practical doubt is insane, or at least blameworthy [Leibniz] |
| 12996 | I know more than I think, since I know I think A then B then C [Leibniz] |
| 13003 | The Cogito doesn't prove existence, because 'I am thinking' already includes 'I am' [Leibniz] |
| 21253 | Descartes needs to demonstrate how other people can attain his clear and distinct conceptions [Leibniz] |
| 12933 | Arithmetic and geometry are implicitly innate, awaiting revelation [Leibniz] |
| 12991 | Children learn language fast, with little instruction and few definitions [Leibniz] |
| 12929 | All of our thoughts come from within the soul, and not from the senses [Leibniz] |
| 12940 | What is left of the 'blank page' if you remove the ideas? [Leibniz] |
| 19358 | Colour and pain must express the nature of their stimuli, without exact resemblance [Leibniz] |
| 12948 | A pain doesn't resemble the movement of a pin, but it resembles the bodily movement pins cause [Leibniz] |
| 13005 | Truth arises among sensations from grounding reasons and from regularities [Leibniz] |
| 4302 | You may experience a universal truth, but only reason can tell you that it is always true [Leibniz] |
| 12947 | We only believe in sensible things when reason helps the senses [Leibniz] |
| 12930 | The senses are confused, and necessities come from distinct intellectual ideas [Leibniz] |
| 13001 | Our sensation of green is a confused idea, like objects blurred by movement [Leibniz] |
| 16279 | General causal theories of knowledge are refuted by mathematics [Lewis] |
| 12949 | Light takes time to reach us, so objects we see may now not exist [Leibniz] |
| 9661 | Induction is just reasonable methods of inferring the unobserved from the observed [Lewis] |
| 5053 | The instances confirming a general truth are never enough to establish its necessity [Leibniz] |
| 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] |
| 12977 | We will only connect our various definitions of gold when we understand it more deeply [Leibniz] |
| 16274 | If the well-ordering of a pack of cards was by shuffling, the explanation would make it more surprising [Lewis] |
| 5054 | Animal thought is a shadow of reasoning, connecting sequences of images by imagination [Leibniz] |
| 12944 | It is a serious mistake to think that we are aware of all of our perceptions [Leibniz] |
| 12951 | Abstraction attends to the general, not the particular, and involves universal truths [Leibniz] |
| 19364 | Volition automatically endeavours to move towards what it sees as good (and away from bad) [Leibniz] |
| 12942 | Memory doesn't make identity; a man who relearned everything would still be the same man [Leibniz] |
| 12973 | We know our own identity by psychological continuity, even if there are some gaps [Leibniz] |
| 19368 | The will determines action, by what is seen as good, but it does not necessitate it [Leibniz] |
| 12935 | Every feeling is the perception of a truth [Leibniz] |
| 12938 | An idea is an independent inner object, which expresses the qualities of things [Leibniz] |
| 12950 | We must distinguish images from exact defined ideas [Leibniz] |
| 12945 | Thoughts correspond to sensations, but ideas are independent of thoughts [Leibniz] |
| 19357 | The idea of green seems simple, but it must be compounded of the ideas of blue and yellow [Leibniz] |
| 12995 | The name 'gold' means what we know of gold, and also further facts about it which only others know [Leibniz] |
| 12807 | The word 'gold' means a hidden constitution known to experts, and not just its appearances [Leibniz] |
| 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] |
| 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] |
| 12946 | The idea of the will includes the understanding [Leibniz] |
| 12964 | If would be absurd not to disagree with someone's taste if it was a taste for poisons [Leibniz] |
| 12958 | Love is pleasure in the perfection, well-being or happiness of its object [Leibniz] |
| 12957 | The good is the virtuous, the pleasing, or the useful [Leibniz] |
| 12962 | Pleasure is a sense of perfection [Leibniz] |
| 12934 | We can't want everyone to have more than their share, so a further standard is needed [Leibniz] |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
| 12936 | There are natural rewards and punishments, like illness after over-indulgence [Leibniz] |
| 9659 | Causation is when at the closest world without the cause, there is no effect either [Lewis] |
| 11856 | Qualities should be predictable from the nature of the subject [Leibniz] |
| 12994 | Gold has a real essence, unknown to us, which produces its properties [Leibniz] |
| 12808 | Part of our idea of gold is its real essence, which is not known to us in detail [Leibniz] |
| 12985 | Maybe motion is definable as 'change of place' [Leibniz] |
| 12952 | Space is an order among actual and possible things [Leibniz] |
| 12955 | If there were duration without change, we could never establish its length [Leibniz] |
| 9666 | It is quite implausible that the future is unreal, as that would terminate everything [Lewis] |
| 12954 | God's essence is the source of possibilities, and his will the source of existents [Leibniz] |
| 12988 | The universe contains everything possible for its perfect harmony [Leibniz] |
| 1414 | A perfection is a simple quality, which is positive and absolute, and has no limit [Leibniz] |
| 21252 | Perfections must have overlapping parts if their incompatibility is to be proved [Leibniz] |
| 19328 | Without the principle of sufficient reason, God's existence could not be demonstrated [Leibniz] |
| 5058 | Animals have thought and sensation, and indestructible immaterial souls [Leibniz] |