222 ideas
| 7504 | Modern science comes from Descartes' view that knowledge doesn't need moral purity [Descartes, by Foucault] |
| 15585 | Later Heidegger sees philosophy as more like poetry than like science [Heidegger, by Polt] |
| 12997 | Analysis is the art of finding the middle term [Leibniz] |
| 13009 | A reason is a known truth which leads to assent to some further truth [Leibniz] |
| 1569 | Descartes impoverished the classical idea of logos, and it no longer covered human experience [Roochnik on Descartes] |
| 2248 | Reason says don't assent to uncertain principles, just as much as totally false ones [Descartes] |
| 2857 | Since Plato all philosophers have followed the herd, except Descartes, stuck in superficial reason [Nietzsche on Descartes] |
| 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] |
| 3641 | It is circular to make truth depend on believing God's existence is true [Arnauld on Descartes] |
| 4524 | Descartes is right that in the Christian view only God can guarantee the reliability of senses [Nietzsche on Descartes] |
| 2290 | Once it is clear that there is a God who is no deceiver, I conclude that clear and distinct perceptions must be true [Descartes] |
| 2266 | My general rule is that everything that I perceive clearly and distinctly is true [Descartes] |
| 4301 | Someone may think a thing is 'clear and distinct', but be wrong [Leibniz on Descartes] |
| 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] |
| 10054 | Arithmetic and geometry achieve some certainty without worrying about existence [Descartes] |
| 12974 | People who can't apply names usually don't understand the thing to which it applies [Leibniz] |
| 13002 | It is always good to reduce the number of axioms [Leibniz] |
| 2252 | Surely maths is true even if I am dreaming? [Descartes] |
| 2430 | I can learn the concepts of duration and number just from observing my own thoughts [Descartes] |
| 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] |
| 12932 | The idea of being must come from our own existence [Leibniz] |
| 12966 | Objects of ideas can be divided into abstract and concrete, and then further subdivided [Leibniz] |
| 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] |
| 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] |
| 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] |
| 2297 | If I can separate two things in my understanding, then God can separate them in reality [Descartes] |
| 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] |
| 3628 | Substance cannot be conceived or explained to others [Gassendi on Descartes] |
| 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] |
| 16631 | If we remove surface qualities from wax, we have an extended, flexible, changeable thing [Descartes] |
| 12968 | A 'substratum' is just a metaphor for whatever supports several predicates [Leibniz] |
| 12931 | Particular truths are just instances of general truths [Leibniz] |
| 12811 | We can't know individuals, or determine their exact individuality [Leibniz] |
| 17865 | Descartes gives an essence by an encapsulating formula [Descartes, by Almog] |
| 12981 | Essence is just the possibility of a thing [Leibniz] |
| 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] |
| 12972 | Bodies, like Theseus's ship, are only the same in appearance, and never strictly the same [Leibniz] |
| 5055 | No two things are totally identical [Leibniz] |
| 12978 | A perfect idea of an object shows that the object is possible [Leibniz] |
| 2301 | We know by thought that what is done cannot be undone [Descartes] |
| 17079 | Proofs of necessity come from the understanding, where they have their source [Leibniz] |
| 3642 | Pythagoras' Theorem doesn't cease to be part of the essence of triangles just because we doubt it [Arnauld on Descartes] |
| 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] |
| 20190 | Belief is not an intellectual state or act, because propositions are affirmed or denied by the will [Descartes, by Zagzebski] |
| 1585 | Descartes tried to model reason on maths instead of 'logos' [Roochnik on Descartes] |
| 1582 | Labelling slightly doubtful things as false is irrational [Roochnik on Descartes] |
| 2256 | Maybe there is only one certain fact, which is that nothing is certain [Descartes] |
| 13006 | Certainty is where practical doubt is insane, or at least blameworthy [Leibniz] |
| 6914 | Descartes transformed 'God is thinkable, so he exists' into 'I think, so I exist' [Descartes, by Feuerbach] |
| 4641 | In the Meditations version of the Cogito he says "I am; I exist", which avoids presenting it as an argument [Descartes, by Baggini /Fosl] |
| 6929 | Modern philosophy set the self-conscious ego in place of God [Descartes, by Feuerbach] |
| 3849 | "I think therefore I am" is the absolute truth of consciousness [Sartre on Descartes] |
| 2258 | I must even exist if I am being deceived by something [Descartes] |
| 2259 | "I am, I exist" is necessarily true every time I utter it or conceive it in my mind [Descartes] |
| 3160 | The Cogito is a transcendental argument, not a piece of a priori knowledge [Rey on Descartes] |
| 2260 | If I don't think, there is no reason to think that I exist [Descartes] |
| 1117 | The Cogito proves subjective experience is basic, but makes false claims about the Self [Russell on Descartes] |
| 2873 | Maybe 'I' am not the thinker, but something produced by thought [Nietzsche on Descartes] |
| 3623 | The Cogito only works if you already understand what thought and existence are [Mersenne on Descartes] |
| 1369 | It is a precondition of the use of the word 'I' that I exist [Ayer on Descartes] |
| 5360 | The thing which experiences may be momentary, and change with the next experience [Russell on Descartes] |
| 2870 | 'I think' assumes I exist, that thinking is known and caused, and that I am doing it [Nietzsche on Descartes] |
| 5188 | A thought doesn't imply other thoughts, or enough thoughts to make up a self [Ayer on Descartes] |
| 3624 | That I perform an activity (thinking) doesn't prove what type of thing I am [Hobbes on Descartes] |
| 3120 | Autistic children seem to use the 'I' concept without seeing themselves as thinkers [Segal on Descartes] |
| 4526 | The Cogito assumes a priori the existence of substance, when actually it is a grammatical custom [Nietzsche on Descartes] |
| 5579 | How can we infer that all thinking involves self-consciousness, just from my own case? [Kant on Descartes] |
| 5580 | My self is not an inference from 'I think', but a presupposition of it [Kant on Descartes] |
| 5587 | We cannot give any information a priori about the nature of the 'thing that thinks' [Kant on Descartes] |
| 5588 | The fact that I am a subject is not enough evidence to show that I am a substantial object [Kant on Descartes] |
| 13923 | Descartes' claim to know his existence before his essence is misleading or absurd [Descartes, by Lowe] |
| 6930 | Modern self-consciousness is a doubtful abstraction; only senses and feelings are certain [Feuerbach on Descartes] |
| 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] |
| 2261 | My perceiving of things may be false, but my seeming to perceive them cannot be false [Descartes] |
| 2257 | I myself could be the author of all these self-delusions [Descartes] |
| 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] |
| 2279 | A triangle has a separate non-invented nature, shown by my ability to prove facts about it [Descartes] |
| 6490 | For Descartes, objects have one primary quality, which is geometrical [Descartes, by Robinson,H] |
| 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] |
| 2295 | Why does pain make us sad? [Descartes] |
| 13005 | Truth arises among sensations from grounding reasons and from regularities [Leibniz] |
| 3627 | Dogs can make the same judgements as us about variable things [Gassendi on Descartes] |
| 2265 | We perceive objects by intellect, not by senses or imagination [Descartes] |
| 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] |
| 2263 | The wax is not perceived by the senses, but by the mind alone [Descartes] |
| 2264 | We don't 'see' men in heavy clothes, we judge them to be men [Descartes] |
| 13001 | Our sensation of green is a confused idea, like objects blurred by movement [Leibniz] |
| 2247 | To achieve good science we must rebuild from the foundations [Descartes] |
| 2255 | Only one certainty is needed for progress (like a lever's fulcrum) [Descartes] |
| 2251 | Even if my body and objects are imaginary, there may be simpler things which are true [Descartes] |
| 6347 | Descartes can't begin again, because sceptics doubt cognitive processes as well as beliefs [Pollock/Cruz on Descartes] |
| 12949 | Light takes time to reach us, so objects we see may now not exist [Leibniz] |
| 2296 | If pain is felt in a lost limb, I cannot be certain that a felt pain exists in my real limbs [Descartes] |
| 3620 | We correct sense errors with other senses, not intellect [Mersenne on Descartes] |
| 3619 | The senses can only report, so perception errors are in the judgment [Gassendi on Descartes] |
| 2249 | It is prudent never to trust your senses if they have deceived you even once [Descartes] |
| 2253 | God may have created nothing, but made his creation appear to me as it does now [Descartes] |
| 2254 | To achieve full scepticism, I imagine a devil who deceives me about the external world and my own body and senses [Descartes] |
| 2305 | Waking actions are joined by memory to all our other actions, unlike actions of which we dream [Descartes] |
| 2294 | I can only sense an object if it is present, and can't fail to sense it when it is [Descartes] |
| 5053 | The instances confirming a general truth are never enough to establish its necessity [Leibniz] |
| 12977 | We will only connect our various definitions of gold when we understand it more deeply [Leibniz] |
| 4862 | Can the pineal gland be moved more slowly or quickly by the mind than by animal spirits? [Spinoza on Descartes] |
| 3850 | We discovers others as well as ourselves in the Cogito [Sartre on Descartes] |
| 2302 | Faculties of the mind aren't parts, as one mind uses them [Descartes] |
| 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] |
| 3151 | Descartes put thought at the centre of the mind problem, but we put sensation [Rey on Descartes] |
| 21800 | Descartes mentions many cognitive faculties, but reduces them to will and intellect [Descartes, by Schmid] |
| 1399 | Imagination and sensation are non-essential to mind [Descartes] |
| 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] |
| 1400 | Some cause must unite the separate temporal sections of a person [Descartes] |
| 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] |
| 1401 | Since I only observe myself to be thinking, I conclude that that is my essence [Descartes] |
| 2299 | I can exist without imagination and sensing, but they can't exist without me [Descartes] |
| 6907 | For Descartes a person's essence is the mind because objects are perceived by mind, not senses [Descartes, by Feuerbach] |
| 2283 | Our 'will' just consists of the feeling that when we are motivated to do something, there are no external pressures [Descartes] |
| 2282 | My capacity to make choices with my free will extends as far as any faculty ever could [Descartes] |
| 19368 | The will determines action, by what is seen as good, but it does not necessitate it [Leibniz] |
| 2276 | The mind is a non-extended thing which thinks [Descartes] |
| 2298 | Mind is not extended, unlike the body [Descartes] |
| 3423 | Descartes is a substance AND property dualist [Descartes, by Kim] |
| 2303 | The mind is utterly indivisible [Descartes] |
| 6153 | Interaction between mental and physical seems to violate the principle of conservation of energy [Rowlands on Descartes] |
| 3625 | The 'thinking thing' may be the physical basis of the mind [Hobbes on Descartes] |
| 2552 | Knowing different aspects of brain/mind doesn't make them different [Rorty on Descartes] |
| 4305 | Descartes gives no clear criterion for individuating mental substances [Cottingham on Descartes] |
| 4861 | Does Descartes have a clear conception of how mind unites with body? [Spinoza on Descartes] |
| 6540 | Even Descartes may concede that mental supervenes on neuroanatomical [Lycan on Descartes] |
| 7733 | Superman's strength is indubitable, Clark Kent's is doubtful, so they are not the same? [Maslin on Descartes] |
| 5686 | In some thoughts I grasp a subject, but also I will or fear or affirm or deny it [Descartes] |
| 12935 | Every feeling is the perception of a truth [Leibniz] |
| 4017 | Descartes created the modern view of rationality, as an internal feature instead of an external vision [Descartes, by Taylor,C] |
| 2284 | I make errors because my will extends beyond my understanding [Descartes] |
| 5685 | True ideas are images, such as of a man, a chimera, or God [Descartes] |
| 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] |
| 3629 | All ideas are adventitious, and come from the senses [Gassendi on Descartes] |
| 2286 | The idea of a supremely perfect being is within me, like the basic concepts of mathematics [Descartes] |
| 2273 | The ideas of God and of my self are innate in me [Descartes] |
| 2285 | I can think of innumerable shapes I have never experienced [Descartes] |
| 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] |
| 12936 | There are natural rewards and punishments, like illness after over-indulgence [Leibniz] |
| 2280 | Many causes are quite baffling, so it is absurd to deduce causes from final purposes [Descartes] |
| 2272 | There must be at least as much in the cause as there is in the effect [Descartes] |
| 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] |
| 12954 | God's essence is the source of possibilities, and his will the source of existents [Leibniz] |
| 2289 | Nothing apart from God could have essential existence, and such a being must be unique and eternal [Descartes] |
| 2269 | God the creator is an intelligent, infinite, powerful substance [Descartes] |
| 2275 | It is self-evident that deception is a natural defect, so God could not be a deceiver [Descartes] |
| 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] |
| 2287 | Existence and God's essence are inseparable, like a valley and a mountain, or a triangle and its properties [Descartes] |
| 2274 | The idea of God in my mind is like the mark a craftsman puts on his work [Descartes] |
| 2268 | One idea leads to another, but there must be an initial idea that contains the reality of all the others [Descartes] |
| 2288 | I cannot think of a supremely perfect being without the supreme perfection of existence [Descartes] |
| 3632 | We mustn't worship God as an image because we have no idea of him [Hobbes on Descartes] |
| 3633 | We can never conceive of an infinite being [Gassendi on Descartes] |
| 5036 | Descartes cannot assume that a most perfect being exists without contradictions [Leibniz on Descartes] |
| 3638 | Existence is not a perfection; it is what makes perfection possible [Gassendi on Descartes] |
| 5058 | Animals have thought and sensation, and indestructible immaterial souls [Leibniz] |
| 3636 | God didn't give us good judgement even about our own lives [Gassendi on Descartes] |
| 2278 | Error arises because my faculty for judging truth is not infinite [Descartes] |
| 2277 | Since God does not wish to deceive me, my judgement won't make errors if I use it properly [Descartes] |
| 2281 | If we ask whether God's works are perfect, we must not take a narrow viewpoint, but look at the universe as a whole [Descartes] |