Ideas of René Descartes, by Theme

[French, 1596 - 1650, Born at La Haye. Pupil at Jesuit College. Lived mostly in Holland. Died working for Queen Christina in Stockholm.]

green numbers give full details    |    back to list of philosophers    |     expand these ideas
1. Philosophy / B. History of Ideas / 5. Later European Thought
7504 Modern science comes from Descartes' view that knowledge doesn't need moral purity [Foucault]
1. Philosophy / D. Nature of Philosophy / 1. Philosophy
3600 Slow and accurate thought makes the greatest progress
1. Philosophy / D. Nature of Philosophy / 2. Invocation to Philosophy
3656 The greatest good for a state is true philosophers
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
3601 Most things in human life seem vain and useless
3602 Almost every daft idea has been expressed by some philosopher
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
21962 Metaphysics is the roots of the tree of science
1. Philosophy / G. Scientific Philosophy / 3. Scientism
3653 My Meditations are the complete foundation of my physics
2. Reason / A. Nature of Reason / 2. Logos
1569 Descartes impoverished the classical idea of logos, and it no longer covered human experience [Roochnik]
2. Reason / A. Nature of Reason / 4. Aims of Reason
3603 Methodical thinking is cautious, analytical, systematic, and panoramic [PG]
2248 Reason says don't assent to uncertain principles, just as much as totally false ones
2. Reason / A. Nature of Reason / 7. Status of Reason
2857 Since Plato all philosophers have followed the herd, except Descartes, stuck in superficial reason [Nietzsche]
2. Reason / F. Fallacies / 4. Circularity
3612 Clear and distinct conceptions are true because a perfect God exists
2290 Once it is clear that there is a God who is no deceiver, I conclude that clear and distinct perceptions must be true
3641 It is circular to make truth depend on believing God's existence is true [Arnauld]
4524 Descartes is right that in the Christian view only God can guarantee the reliability of senses [Nietzsche]
3659 I know the truth that God exists and is the author of truth
3. Truth / A. Truth Problems / 2. Defining Truth
4736 Truth is such a transcendentally clear notion that it cannot be further defined
3. Truth / A. Truth Problems / 8. Subjective Truth
3610 Truth is clear and distinct conception - of which it is hard to be sure
2266 My general rule is that everything that I perceive clearly and distinctly is true
4301 Someone may think a thing is 'clear and distinct', but be wrong [Leibniz]
3. Truth / D. Coherence Truth / 1. Coherence Truth
4298 All items of possible human knowledge are interconnected, and can be reached by inference
5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
10054 Arithmetic and geometry achieve some certainty without worrying about existence
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
2252 Surely maths is true even if I am dreaming?
2430 I can learn the concepts of duration and number just from observing my own thoughts
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
13445 Descartes showed a one-one order-preserving match between points on a line and the real numbers [Hart,WD]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
21963 It is possible that an omnipotent God might make one and two fail to equal three
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
3644 Two things being joined together doesn't prove they are the same
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
16635 Incorporeal substances are powers or forces [Pasnau]
8. Modes of Existence / C. Powers and Dispositions / 3. Powers as Derived
16744 All powers can be explained by obvious features like size, shape and motion of matter
8. Modes of Existence / D. Universals / 1. Universals
5016 Five universals: genus, species, difference, property, accident
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
5015 A universal is a single idea applied to individual things that are similar to one another
9. Objects / B. Unity of Objects / 1. Unifying an Object / c. Unity as conceptual
2297 If I can separate two things in my understanding, then God can separate them in reality
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
3626 Knowing the attributes is enough to reveal a substance
16630 If we perceive an attribute, we infer the existence of some substance
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
5013 A substance needs nothing else in order to exist
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
3628 Substance cannot be conceived or explained to others [Gassendi]
16774 Descartes thinks distinguishing substances from aggregates is pointless [Pasnau]
9. Objects / C. Structure of Objects / 7. Substratum
16631 If we remove surface qualities from wax, we have an extended, flexible, changeable thing
9. Objects / D. Essence of Objects / 4. Essence as Definition
17865 Descartes gives an essence by an encapsulating formula [Almog]
9. Objects / D. Essence of Objects / 9. Essence and Properties
16633 A substance has one principal property which is its nature and essence
9. Objects / D. Essence of Objects / 15. Against Essentialism
12251 Substantial forms are not understood, and explain nothing
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
2301 We know by thought that what is done cannot be undone
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / b. Conceivable but impossible
3642 Pythagoras' Theorem doesn't cease to be part of the essence of triangles just because we doubt it [Arnauld]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
3605 We can believe a thing without knowing we believe it
11. Knowledge Aims / A. Knowledge / 4. Belief / d. Cause of beliefs
20190 Belief is not an intellectual state or act, because propositions are affirmed or denied by the will [Zagzebski]
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
9807 In pursuing truth, anything less certain than mathematics is a waste of time
1583 In morals Descartes accepts the conventional, but rejects it in epistemology [Roochnik]
2256 Maybe there is only one certain fact, which is that nothing is certain
1582 Labelling slightly doubtful things as false is irrational [Roochnik]
1585 Descartes tried to model reason on maths instead of 'logos' [Roochnik]
3657 Understanding, not the senses, gives certainty
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
3607 In thinking everything else false, my own existence remains totally certain
3849 "I think therefore I am" is the absolute truth of consciousness [Sartre]
2260 If I don't think, there is no reason to think that I exist
3622 The Cogito is not a syllogism but a self-evident intuition
2258 I must even exist if I am being deceived by something
3160 The Cogito is a transcendental argument, not a piece of a priori knowledge [Rey]
2259 "I am, I exist" is necessarily true every time I utter it or conceive it in my mind
6914 Descartes transformed 'God is thinkable, so he exists' into 'I think, so I exist' [Feuerbach]
4641 In the Meditations version of the Cogito he says "I am; I exist", which avoids presenting it as an argument [Baggini /Fosl]
6929 Modern philosophy set the self-conscious ego in place of God [Feuerbach]
3658 Total doubt can't include your existence while doubting
5005 I think, therefore I am, because for a thinking thing to not exist is a contradiction
5006 'Thought' is all our conscious awareness, including feeling as well as understanding
11. Knowledge Aims / B. Certain Knowledge / 5. Cogito Critique
5360 The thing which experiences may be momentary, and change with the next experience [Russell]
2870 'I think' assumes I exist, that thinking is known and caused, and that I am doing it [Nietzsche]
5188 A thought doesn't imply other thoughts, or enough thoughts to make up a self [Ayer]
3624 That I perform an activity (thinking) doesn't prove what type of thing I am [Hobbes]
4526 The Cogito assumes a priori the existence of substance, when actually it is a grammatical custom [Nietzsche]
5579 How can we infer that all thinking involves self-consciousness, just from my own case? [Kant]
1117 The Cogito proves subjective experience is basic, but makes false claims about the Self [Russell]
3120 Autistic children seem to use the 'I' concept without seeing themselves as thinkers [Segal]
3623 The Cogito only works if you already understand what thought and existence are [Mersenne]
1369 It is a precondition of the use of the word 'I' that I exist [Ayer]
5580 My self is not an inference from 'I think', but a presupposition of it [Kant]
5587 We cannot give any information a priori about the nature of the 'thing that thinks' [Kant]
5588 The fact that I am a subject is not enough evidence to show that I am a substantial object [Kant]
13923 Descartes' claim to know his existence before his essence is misleading or absurd [Lowe]
6930 Modern self-consciousness is a doubtful abstraction; only senses and feelings are certain [Feuerbach]
2873 Maybe 'I' am not the thinker, but something produced by thought [Nietzsche]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
2261 My perceiving of things may be false, but my seeming to perceive them cannot be false
11. Knowledge Aims / C. Knowing Reality / 4. Solipsism
2257 I myself could be the author of all these self-delusions
12. Knowledge Sources / A. A Priori Knowledge / 3. Innate Knowledge / a. Innate knowledge
3630 Our thinking about external things doesn't disprove the existence of innate ideas
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
2279 A triangle has a separate non-invented nature, shown by my ability to prove facts about it
2602 What experience could prove 'If a=c and b=c then a=b'?
5012 'Nothing comes from nothing' is an eternal truth found within the mind
12. Knowledge Sources / A. A Priori Knowledge / 6. A Priori from Reason
3617 I aim to find the principles and causes of everything, using the seeds within my mind
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / c. Primary qualities
6490 For Descartes, objects have one primary quality, which is geometrical [Robinson,H]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / d. Secondary qualities
22593 Our sensation of light may not be the same as what produces the sensation
12. Knowledge Sources / B. Perception / 3. Representation
7400 Descartes said images can refer to objects without resembling them (as words do) [Tuck]
12. Knowledge Sources / B. Perception / 5. Interpretation
2295 Why does pain make us sad?
12. Knowledge Sources / C. Rationalism / 1. Rationalism
3611 Understanding, rather than imagination or senses, gives knowledge
2263 The wax is not perceived by the senses, but by the mind alone
3627 Dogs can make the same judgements as us about variable things [Gassendi]
2265 We perceive objects by intellect, not by senses or imagination
2264 We don't 'see' men in heavy clothes, we judge them to be men
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
3606 I was searching for reliable rock under the shifting sand
2247 To achieve good science we must rebuild from the foundations
2255 Only one certainty is needed for progress (like a lever's fulcrum)
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
5004 We can know basic Principles without further knowledge, but not the other way round
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
2251 Even if my body and objects are imaginary, there may be simpler things which are true
6347 Descartes can't begin again, because sceptics doubt cognitive processes as well as beliefs [Pollock/Cruz]
13. Knowledge Criteria / D. Scepticism / 3. Illusion Scepticism
3621 Only judgement decides which of our senses are reliable
3619 The senses can only report, so perception errors are in the judgment [Gassendi]
2296 If pain is felt in a lost limb, I cannot be certain that a felt pain exists in my real limbs
2249 It is prudent never to trust your senses if they have deceived you even once
3620 We correct sense errors with other senses, not intellect [Mersenne]
13. Knowledge Criteria / D. Scepticism / 4. Demon Scepticism
2253 God may have created nothing, but made his creation appear to me as it does now
2254 To achieve full scepticism, I imagine a devil who deceives me about the external world and my own body and senses
13. Knowledge Criteria / D. Scepticism / 5. Dream Scepticism
2305 Waking actions are joined by memory to all our other actions, unlike actions of which we dream
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
3604 When rebuilding a house, one needs alternative lodgings
2294 I can only sense an object if it is present, and can't fail to sense it when it is
14. Science / A. Basis of Science / 3. Experiment
3618 Only experiments can settle disagreements between rival explanations
15. Nature of Minds / A. Nature of Mind / 3. Mental Causation
4862 Can the pineal gland be moved more slowly or quickly by the mind than by animal spirits? [Spinoza]
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / c. Knowing other minds
3850 We discovers others as well as ourselves in the Cogito [Sartre]
15. Nature of Minds / A. Nature of Mind / 5. Unity of Mind
2302 Faculties of the mind aren't parts, as one mind uses them
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
3615 Little reason is needed to speak, so animals have no reason at all
15. Nature of Minds / B. Features of Minds / 1. Consciousness / b. Essence of consciousness
5014 We can understand thinking occuring without imagination or sensation
15. Nature of Minds / B. Features of Minds / 2. Unconscious Mind
16634 I can't be unaware of anything which is in me
15. Nature of Minds / B. Features of Minds / 5. Qualia / a. Nature of qualia
3151 Descartes put thought at the centre of the mind problem, but we put sensation [Rey]
15. Nature of Minds / C. Capacities of Minds / 1. Faculties
21800 Descartes mentions many cognitive faculties, but reduces them to will and intellect [Schmid]
15. Nature of Minds / C. Capacities of Minds / 2. Imagination
1399 Imagination and sensation are non-essential to mind
16. Persons / A. Concept of a Person / 1. Existence of Persons
1400 Some cause must unite the separate temporal sections of a person
16. Persons / B. Nature of the Self / 3. Self as Non-physical
3609 I am a thinking substance, which doesn't need a place or material support
16. Persons / D. Continuity of the Self / 7. Self and Thinking
1401 Since I only observe myself to be thinking, I conclude that that is my essence
2299 I can exist without imagination and sensing, but they can't exist without me
6907 For Descartes a person's essence is the mind because objects are perceived by mind, not senses [Feuerbach]
5017 In thinking we shut ourselves off from other substances, showing our identity and separateness
16. Persons / F. Free Will / 1. Nature of Free Will
2283 Our 'will' just consists of the feeling that when we are motivated to do something, there are no external pressures
5010 Our free will is so self-evident to us that it must be a basic innate idea
16. Persons / F. Free Will / 3. Constraints on the will
3789 The more reasons that compel me, the freer I am
16. Persons / F. Free Will / 4. For Free Will
2282 My capacity to make choices with my free will extends as far as any faculty ever could
4310 We have inner awareness of our freedom
17. Mind and Body / A. Mind-Body Dualism / 1. Dualism
3608 I can deny my body and the world, but not my own existence
3613 Reason is universal in its responses, but a physical machine is constrained by its organs
2276 The mind is a non-extended thing which thinks
2298 Mind is not extended, unlike the body
3423 Descartes is a substance AND property dualist [Kim]
2303 The mind is utterly indivisible
5011 There are two ultimate classes of existence: thinking substance and extended substance
17. Mind and Body / A. Mind-Body Dualism / 2. Interactionism
3616 The soul must unite with the body to have appetites and sensations
6153 Interaction between mental and physical seems to violate the principle of conservation of energy [Rowlands]
6553 Descartes discussed the interaction problem, and compared it with gravity [Lycan]
3654 The pineal gland links soul to body, and unites the two symmetrical sides of the body [PG]
17. Mind and Body / A. Mind-Body Dualism / 8. Dualism of Mind Critique
3625 The 'thinking thing' may be the physical basis of the mind [Hobbes]
2552 Knowing different aspects of brain/mind doesn't make them different [Rorty]
4305 Descartes gives no clear criterion for individuating mental substances [Cottingham]
4861 Does Descartes have a clear conception of how mind unites with body? [Spinoza]
6540 Even Descartes may concede that mental supervenes on neuroanatomical [Lycan]
7733 Superman's strength is indubitable, Clark Kent's is doubtful, so they are not the same? [Maslin]
17. Mind and Body / D. Property Dualism / 5. Supervenience of mind
5018 Even if tightly united, mind and body are different, as God could separate them
17. Mind and Body / E. Mind as Physical / 6. Conceptual Dualism
3643 The concept of mind excludes body, and vice versa
18. Thought / A. Modes of Thought / 2. Propositional Attitudes
5686 In some thoughts I grasp a subject, but also I will or fear or affirm or deny it
18. Thought / A. Modes of Thought / 3. Emotions
4015 For Descartes passions are God-given preservers of the mind-body union [Taylor,C]
4313 Are there a few primary passions (say, joy, sadness and desire)? [Cottingham]
18. Thought / A. Modes of Thought / 5. Rationality / b. Human rationality
4017 Descartes created the modern view of rationality, as an internal feature instead of an external vision [Taylor,C]
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
2284 I make errors because my will extends beyond my understanding
5007 Most errors of judgement result from an inaccurate perception of the facts
18. Thought / B. Mechanics of Thought / 6. Artificial Thought / c. Turing Test
3614 A machine could speak in response to physical stimulus, but not hold a conversation
18. Thought / C. Content / 1. Content
3629 All ideas are adventitious, and come from the senses [Gassendi]
18. Thought / C. Content / 2. Ideas
5685 True ideas are images, such as of a man, a chimera, or God
18. Thought / D. Concepts / 2. Origin of Concepts / c. Nativist concepts
3631 A blind man may still contain the idea of colour
2286 The idea of a supremely perfect being is within me, like the basic concepts of mathematics
2285 I can think of innumerable shapes I have never experienced
2273 The ideas of God and of my self are innate in me
2600 The mind's innate ideas are part of its capacity for thought
2601 Qualia must be innate, because physical motions do not contain them
20. Action / B. Preliminaries of Action / 2. Willed Action / b. Volitionism
20037 Merely willing to walk leads to our walking
20. Action / C. Motives for Action / 4. Responsibility for Actions
5008 The greatest perfection of man is to act by free will, and thus merit praise or blame
5009 We do not praise the acts of an efficient automaton, as their acts are necessary
22. Metaethics / A. Value / 2. Values / d. Death
16763 We don't die because the soul departs; the soul departs because the organs cease functioning
23. Ethics / C. Virtue Theory / 1. Virtue Theory / d. Virtue theory critique
1581 Greeks elevate virtues enormously, but never explain them
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
4016 Descartes makes strength of will the central virtue [Taylor,C]
23. Ethics / F. Existentialism / 5. Existence-Essence
3635 Essence must be known before we discuss existence
26. Natural Theory / A. Speculations on Nature / 1. Nature
19676 Nature is devoid of thought [Meillassoux]
15987 Physics only needs geometry or abstract mathematics, which can explain and demonstrate everything
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / a. Final purpose
2280 Many causes are quite baffling, so it is absurd to deduce causes from final purposes
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / c. Purpose denied
12730 We will not try to understand natural or divine ends, or final causes
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
16569 The Hot, Cold, Wet and Dry of the philosophers need themselves to be explained
26. Natural Theory / A. Speculations on Nature / 7. Later Matter Theories / c. Matter as extension
6518 Matter can't just be Descartes's geometry, because a filler of the spaces is needed [Robinson,H]
16601 Matter is not hard, heavy or coloured, but merely extended in space
16684 Impenetrability only belongs to the essence of extension
26. Natural Theory / C. Causation / 8. Particular Causation / c. Conditions of causation
2272 There must be at least as much in the cause as there is in the effect
26. Natural Theory / D. Laws of Nature / 7. Strictness of Laws
16686 God has established laws throughout nature, and implanted ideas of them within us
27. Natural Reality / A. Classical Physics / 1. Mechanics / b. Laws of motion
20964 Descartes said there was conservation of 'quantity of motion' [Papineau]
28. God / A. Divine Nature / 2. Divine Nature
2269 God the creator is an intelligent, infinite, powerful substance
2289 Nothing apart from God could have essential existence, and such a being must be unique and eternal
28. God / A. Divine Nature / 3. Divine Perfections
2275 It is self-evident that deception is a natural defect, so God could not be a deceiver
28. God / A. Divine Nature / 6. Divine Morality / d. God decrees morality
3637 Ideas in God's mind only have value if he makes it so
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
2287 Existence and God's essence are inseparable, like a valley and a mountain, or a triangle and its properties
2288 I cannot think of a supremely perfect being without the supreme perfection of existence
3640 Possible existence is a perfection in the idea of a triangle
2268 One idea leads to another, but there must be an initial idea that contains the reality of all the others
2274 The idea of God in my mind is like the mark a craftsman puts on his work
3639 Necessary existence is a property which is uniquely part of God's essence
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
3632 We mustn't worship God as an image because we have no idea of him [Hobbes]
3633 We can never conceive of an infinite being [Gassendi]
5036 Descartes cannot assume that a most perfect being exists without contradictions [Leibniz]
3638 Existence is not a perfection; it is what makes perfection possible [Gassendi]
28. God / B. Proving God / 3. Proofs of Evidence / a. Cosmological Proof
3634 We can't prove a first cause from our inability to grasp infinity
28. God / C. Attitudes to God / 5. Atheism
16712 Atheism is an atrocious and intolerable crime in any country
3660 Atheism arises from empiricism, because God is intangible
29. Religion / B. Monotheistic Religion / 4. Christianity / c. Angels
16772 An angelic mind would not experience pain, even when connected to a human body [Pasnau]
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
3652 I can't prove the soul is indestructible, only that it is separate from the mortal body
29. Religion / D. Religious Issues / 3. Problem of Evil / c. Human Error
2278 Error arises because my faculty for judging truth is not infinite
3636 God didn't give us good judgement even about our own lives [Gassendi]
2277 Since God does not wish to deceive me, my judgement won't make errors if I use it properly
29. Religion / D. Religious Issues / 3. Problem of Evil / d. Natural Evil
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