René Descartes
Doubt everything you can, and one thing remains certain – that you, who are thinking, exist – and mind and body are two different kinds of thing.
Placement
Methodical doubt leads to an unshakable foundation: I think, therefore I am. Mind and body are two substances.
Key ideas
- Cogito ergo sum
- Methodical doubt
- Mind–body dualism
Influence
Influenced by 4
Sextus Empiricus
influenced by
Descartes’ doubt in the Meditations (1641) uses the sceptical arguments revived from Sextus; in the Second Replies he says he had seen many ancient sceptical writings. R. Descartes, Meditationes (1641), First Meditation and Second Replies; R. H. Popkin, The History of Scepticism from Savonarola to Bayle (2003); SEP “Ancient Skepticism”
Evidence: also in InPhO · InPhO
Sextus Empiricus › c. 160–210
Augustine
influenced by
Shown Augustine’s ‘if I am mistaken, I exist’ (City of God), Descartes acknowledged the parallel but stressed his different use of it (letter to Colvius, 1640). R. Descartes, letter to A. Colvius (Nov. 1640); Augustine, De civitate Dei (si fallor, sum); SEP “Saint Augustine”
Evidence: AI draft
Augustine › 354–430
Michel de Montaigne
influenced by
Descartes’ Discourse on Method (1637) echoes Montaigne in its first-person form and in the lesson drawn from the diversity of customs, without naming him. R. Descartes, Discours de la méthode (1637), ed. É. Gilson, Discours de la méthode: texte et commentaire (1925); SEP “Michel de Montaigne”
Evidence: also in InPhO · InPhO
Michel de Montaigne › 1533–1592
Francisco Suárez
influenced by disputed ✓
In the Fourth Replies (1641) Descartes cited Suárez’s Metaphysical Disputations on material falsity, the one place he names him; how far Suárez shaped him is disputed. R. Descartes, Fourth Replies (1641); F. Suárez, Disputationes metaphysicae (1597); R. Ariew, Descartes and the Last Scholastics (1999)
Francisco Suárez › 1548–1617
Influenced 13
Nicolas Malebranche
influenced ✓
Reading Descartes’ Treatise on Man in 1664 turned Malebranche to philosophy; The Search after Truth (1674–75) keeps Cartesian dualism and extension as the essence of matter. N. Malebranche, De la recherche de la vérité (1674–75); SEP “Nicolas Malebranche”
Nicolas Malebranche › 1638–1715
Georg Wilhelm Friedrich Hegel
influenced ✓
Hegel made Descartes’ principle of thinking the start of modern philosophy: with him ‘we are at home’ (Lectures on the History of Philosophy, 1833–36). G. W. F. Hegel, Vorlesungen über die Geschichte der Philosophie III (ed. K. L. Michelet, 1836), section on Descartes
Georg Wilhelm Friedrich Hegel › 1770–1831
Edmund Husserl
influenced
In the Cartesian Meditations (1931) Husserl radicalised Descartes’s way to the ego cogito into transcendental phenomenology, rejecting the ego as a thinking substance. E. Husserl, Méditations cartésiennes (1931); Cartesianische Meditationen (1950); SEP “Edmund Husserl”
Evidence: also in InPhO · InPhO
Edmund Husserl › 1859–1938
Jean-Paul Sartre
influenced
Sartre took the cogito as the starting point of philosophy and in ‘Cartesian Freedom’ (1946) argued that Descartes conceived an absolute freedom but transferred it to God. J.-P. Sartre, “La liberté cartésienne” (1946), in Situations I (1947); L’existentialisme est un humanisme (1946); SEP “Jean-Paul Sartre”
Evidence: AI draft
Jean-Paul Sartre › 1905–1980
Emmanuel Levinas
influenced
Levinas took Descartes’s idea of the infinite, which exceeds the mind that thinks it, as the structure of the relation to the Other (Totality and Infinity, 1961). E. Levinas, Totalité et infini (1961); R. Descartes, Meditationes de prima philosophia (1641), third meditation; SEP “Emmanuel Levinas”
Evidence: also in InPhO · InPhO
Emmanuel Levinas › 1906–1995
Harry Frankfurt
influenced ✓
Frankfurt read Descartes’s Meditations as a defence of reason, asking whether reason can vindicate itself against doubts from demons, dreams and madness (Demons, Dreamers, and Madmen, 1970). H. G. Frankfurt, Demons, Dreamers, and Madmen: The Defense of Reason in Descartes’s Meditations (1970); SEP “René Descartes”
Evidence: also in Wikidata · Wikidata
Harry Frankfurt › 1929–2023
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Pierre Bayle
influenced
Bayle taught Cartesian philosophy at Sedan and Rotterdam, and in his Dictionary (1697) turned the Cartesian arguments against sensible qualities against the reality of extension itself. P. Bayle, Dictionnaire historique et critique (1697), “Zénon d’Élée”, “Pyrrhon”; R. H. Popkin, The History of Scepticism from Savonarola to Bayle (2003); SEP “Pierre Bayle”
Evidence: AI draft
Pierre Bayle › 1647–1706
Mary Astell
influenced
In A Serious Proposal to the Ladies, Part II (1697), Astell adapted Descartes’ rules of method to show that women can reason as well as men. M. Astell, A Serious Proposal to the Ladies, Part II (1697); SEP “Mary Astell”
Evidence: AI draft
Mary Astell › 1666–1731
George Berkeley
influenced
Berkeley accepted the Cartesian starting point that we immediately perceive only our ideas, but used it to deny the material world Descartes had tried to prove (Principles, 1710). G. Berkeley, A Treatise concerning the Principles of Human Knowledge (1710); Three Dialogues between Hylas and Philonous (1713); SEP “George Berkeley”
Evidence: AI draft
George Berkeley › 1685–1753
Taha Hussein
influenced
Taha Hussein opened On Pre-Islamic Poetry (1926) by adopting Descartes’ method: the scholar must set aside what he knows and believes and doubt the transmitted sources. Ṭāhā Ḥusayn, Fī l-shiʿr al-jāhilī (1926), introduction; P. Cachia, Ṭāhā Ḥusayn (1956)
Evidence: AI draft
Taha Hussein › 1889–1973
Simone Weil
influenced
Weil’s diploma thesis read Descartes as a philosopher of methodical work, for whom perception and knowledge arise from action on the world (Science et perception dans Descartes, 1930). S. Weil, Science et perception dans Descartes (diplôme d’études supérieures, 1930), in Œuvres complètes I (1988)
Evidence: AI draft
Simone Weil › 1909–1943
Jaakko Hintikka
influenced
Hintikka argued that Descartes’s cogito is not an inference but a performance: the thought ‘I do not exist’ defeats itself whenever it is thought or uttered (1962). J. Hintikka, “Cogito, ergo sum: Inference or Performance?”, Philosophical Review 71 (1962)
Evidence: AI draft
Jaakko Hintikka › 1929–2015
David Chalmers
influenced
Chalmers revived a Cartesian conceivability argument – if zombies are conceivable, consciousness is not physical – for a dualism of properties rather than substances (The Conscious Mind, 1996). D. J. Chalmers, The Conscious Mind (1996); R. Descartes, Meditationes de prima philosophia (1641), sixth meditation; SEP “Zombies”
Evidence: AI draft
David Chalmers › b. 1966
Criticism
Mutual critique 1
Pierre Gassendi ⇄ mutual
criticised
Descartes replied to Gassendi’s Fifth Objections (1641) addressing him as ‘flesh’ and arguing that Gassendi, wanting to grasp everything through images, confused pure understanding with imagination. Descartes, Fifth Replies (AT VII 347–390); letter to Clerselier, 12 Jan. 1646 (AT IX-1 202–217)
Evidence: AI draft
criticised by
In the Fifth Objections (1641; expanded as Disquisitio metaphysica, 1644) Gassendi doubted innate ideas and asked how an unextended mind could move a body. Descartes, Meditationes (1641), Fifth Objections (AT VII 256–346); P. Gassendi, Disquisitio metaphysica (1644); SEP “Pierre Gassendi”
Evidence: AI draft
Pierre Gassendi › 1592–1655
Criticized by 28
Antoine Arnauld influenced byinfluenced
influenced by
In the Fourth Replies (1641) Descartes accepted Arnauld’s advice and added to the Synopsis that the Fourth Meditation concerns error in judging truth, not sin. R. Descartes, Meditationes (1641), Synopsis and Fourth Replies; SEP “Antoine Arnauld”
Evidence: AI draft
influenced
Arnauld became a leading Cartesian: the Port-Royal Logic (1662, with Pierre Nicole) builds on Descartes’ clear and distinct ideas and his method. A. Arnauld and P. Nicole, La Logique ou l’art de penser (1662); SEP “Antoine Arnauld”
Evidence: also in InPhO · InPhO
criticised by
In the Fourth Objections (1641) Arnauld charged Descartes with circular reasoning about God and clear perception and questioned his denial of souls to animals. Descartes, Meditationes (1641), Fourth Objections (AT VII 197–218); SEP “Antoine Arnauld”
Evidence: AI draft
Antoine Arnauld › 1612–1694
Elisabeth of Bohemia influenced byinfluenced
influenced by
Elisabeth’s questions about the union of mind and body and the control of the passions led Descartes to write The Passions of the Soul (1649). R. Descartes, Les Passions de l’âme (1649); Elisabeth–Descartes correspondence (1643–1649); SEP “Elisabeth of Bohemia”
Evidence: AI draft
influenced
From 1643 Elisabeth studied Descartes’ philosophy with him by letter; he dedicated the Principles of Philosophy (1644) to her, and in 1645 they discussed Seneca on happiness. Elisabeth of Bohemia and R. Descartes, The Correspondence, ed. and tr. L. Shapiro (2007); R. Descartes, Principia philosophiae (1644), dedication; SEP “Elisabeth of Bohemia”
Evidence: AI draft
criticised by
Elisabeth asked Descartes how an unextended thinking soul could move the body, since motion seems to require contact and extension (letter of 6/16 May 1643). Elisabeth to Descartes, 6/16 May 1643 (AT III 660–662); SEP “Elisabeth of Bohemia”
Evidence: AI draft
Elisabeth of Bohemia › 1618–1680
John Locke influenced
influenced ✓
According to Damaris Masham, Descartes’ writings first gave Locke a relish for philosophy, for he found them intelligible even where he disagreed (letter to Le Clerc, 1705). D. Masham, letter to J. Le Clerc (Jan. 1705); M. Cranston, John Locke: A Biography (1957); SEP “John Locke”
criticised by
Locke denied innate ideas (Essay, 1689, Book I) and, against the Cartesians, that the soul always thinks, since thinking is its action, not its essence (II.i.10). J. Locke, An Essay concerning Human Understanding (1689), I.ii–iv, II.i.10–19; SEP “John Locke”
Evidence: AI draft
John Locke › 1632–1704
Baruch de Spinoza influenced
influenced ✓
Spinoza’s first published book, Principles of Cartesian Philosophy (1663), set out Descartes’ Principles in geometrical order, with his Metaphysical Thoughts appended. B. Spinoza, Renati Des Cartes Principiorum philosophiae pars I et II, more geometrico demonstratae (1663), with Cogitata metaphysica; SEP “Baruch Spinoza”
criticised by
Spinoza called Descartes’ account of the mind steering the body through the pineal gland ‘more occult than any occult quality’ (Ethics, 1677, V, Preface). B. Spinoza, Ethica (1677), V, Praefatio; II P48–49 (against free will); SEP “Baruch Spinoza”
Evidence: AI draft
Baruch de Spinoza › 1632–1677
Isaac Newton influenced
influenced ✓
Newton studied Descartes’ Géométrie and Principia philosophiae (1660s); his first law is close to Descartes’ laws of nature, and his title echoes Descartes’ (Principia, 1687). I. Newton, Philosophiae naturalis principia mathematica (1687); R. Descartes, Principia philosophiae (1644); R. S. Westfall, Never at Rest (1980); SEP “Isaac Newton”
Evidence: also in Wikidata · Wikidata
criticised by
Newton argued that Descartes’ vortices cannot account for Kepler’s laws (Principia II, 1687), and rejected his identification of space with body (De gravitatione). I. Newton, Principia (1687) II, scholium to prop. 53; De gravitatione et aequipondio fluidorum; SEP “Newton’s Philosophy”
Evidence: AI draft
Isaac Newton › 1643–1727
Gottfried Wilhelm Leibniz influenced
influenced ✓
In Meditations on Knowledge, Truth and Ideas (1684) Leibniz refined Descartes’ clear and distinct ideas and completed his ontological proof by requiring God’s possibility to be shown. G. W. Leibniz, Meditationes de cognitione, veritate et ideis (Acta Eruditorum, 1684); SEP “Gottfried Wilhelm Leibniz”
criticised by
Leibniz argued that Descartes’ law conserving quantity of motion is false: what is conserved is living force, mv² (Brevis demonstratio, 1686; Discourse on Metaphysics, §17). G. W. Leibniz, Brevis demonstratio erroris memorabilis Cartesii (Acta Eruditorum, 1686); Discours de métaphysique (1686), §17
Evidence: AI draft
Gottfried Wilhelm Leibniz › 1646–1716
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Thomas Hobbes
criticised by
Hobbes argued that a thinking thing might be corporeal and that we have no idea of God or of the soul in Descartes’ sense (Third Objections, 1641). Descartes, Meditationes (1641), Third Objections and Replies (AT VII 171–196)
Evidence: AI draft
Thomas Hobbes › 1588–1679
Margaret Cavendish
criticised by
In Philosophical Letters (1664) Cavendish rejected Descartes’ separation of an immaterial mind from inert matter, holding that all matter is self-moving, perceptive and rational. M. Cavendish, Philosophical Letters (1664), Part I; SEP “Margaret Lucas Cavendish”
Evidence: AI draft
Margaret Cavendish › 1623–1673
Blaise Pascal
criticised by
Pascal could not forgive Descartes for wanting to do without God, needing him only for a flick to set the world in motion (Pensées, fr. 1001 Lafuma). B. Pascal, Pensées, ed. Lafuma, fr. 1001 (Brunschvicg 77); fr. 887 (B 78: “Descartes inutile et incertain”)
Evidence: AI draft
Blaise Pascal › 1623–1662
Anne Conway
criticised by
Conway held against Descartes that body and spirit differ only in degree, so matter is not dead extension (Principles of the Most Ancient and Modern Philosophy, 1690). A. Conway, Principia philosophiae antiquissimae et recentissimae (1690), chs. 7–9; SEP “Anne Conway”
Evidence: AI draft
Anne Conway › 1631–1679
Giambattista Vico
criticised by
Vico objected that Descartes’ cogito gives consciousness, not knowledge, of being, for we know truly only what we make (De antiquissima Italorum sapientia, 1710). G. Vico, De antiquissima Italorum sapientia (1710), ch. I; De nostri temporis studiorum ratione (1709); SEP “Giambattista Vico”
Evidence: AI draft
Giambattista Vico › 1668–1744
Anton Wilhelm Amo
criticised by
Amo turned against Cartesian interaction: the mind, active and immaterial, cannot sense or suffer, so sensation belongs to the living, organic body (De humanae mentis apatheia, 1734). A. W. Amo, Dissertatio inauguralis philosophica de humanae mentis apatheia (Wittenberg, 1734); S. Menn & J. E. H. Smith (eds.), Anton Wilhelm Amo’s Philosophical Dissertations on Mind and Body (2020)
Evidence: AI draft
Anton Wilhelm Amo › c. 1703–1759
David Hume
criticised by
Hume objected that Descartes’ antecedent universal doubt would be incurable, since no principle could restore trust in our faculties once all were suspended (Enquiry, 1748, XII). D. Hume, An Enquiry concerning Human Understanding (1748), XII.i; SEP “David Hume”
Evidence: AI draft
David Hume › 1711–1776
Immanuel Kant
criticised by
Kant rejected Descartes’ inference from ‘I think’ to a simple thinking substance (Paralogisms) and argued that inner experience presupposes outer objects (Refutation of Idealism, B 274–279). I. Kant, Kritik der reinen Vernunft, A 341–405 / B 399–432 (Paralogisms); B 274–279 (Refutation of Idealism)
Evidence: AI draft
Immanuel Kant › 1724–1804
Charles Sanders Peirce
criticised by
Peirce rejected Cartesian doubt – ‘let us not pretend to doubt in philosophy what we do not doubt in our hearts’ (‘Some Consequences of Four Incapacities’, 1868). C. S. Peirce, “Some Consequences of Four Incapacities”, Journal of Speculative Philosophy 2 (1868); SEP “Charles Sanders Peirce”
Evidence: AI draft
Charles Sanders Peirce › 1839–1914
Gaston Bachelard
criticised by
Bachelard called for a ‘non-Cartesian epistemology’: modern physics replaces Descartes’ simple, clear and distinct ideas with complex constructions (Le nouvel esprit scientifique, 1934, ch. 6). G. Bachelard, Le nouvel esprit scientifique (1934), ch. 6 ‘L’épistémologie non-cartésienne’
Evidence: AI draft
Gaston Bachelard › 1884–1962
Martin Heidegger
criticised by
Heidegger objected that Descartes leaves the being of the ‘sum’ unexamined and reduces the world to measurable extension, missing being-in-the-world (Being and Time, 1927, §§ 6, 19–21). M. Heidegger, Sein und Zeit (1927), §§ 6, 19–21; SEP “Martin Heidegger”
Evidence: AI draft
Martin Heidegger › 1889–1976
Norbert Elias
criticised by
Elias traced the image of the individual as a homo clausus, sealed off from others, to Descartes’ cogito, and opposed it with figurations (Civilizing Process, 1969 introduction). N. Elias, Über den Prozeß der Zivilisation, 2nd ed. (1969), Introduction; Die Gesellschaft der Individuen (1987), Part II
Evidence: AI draft
Norbert Elias › 1897–1990
Gilbert Ryle
criticised by
Ryle called the Cartesian ‘official doctrine’ of mind and body the dogma of the ‘Ghost in the Machine’, a category mistake (The Concept of Mind, 1949). G. Ryle, The Concept of Mind (1949), ch. 1
Evidence: AI draft
Gilbert Ryle › 1900–1976
Maurice Merleau-Ponty
criticised by
Merleau-Ponty rejected Descartes’ split between thinking mind and extended body, analysing perception through the lived body (Phenomenology of Perception, 1945); Eye and Mind (1961) contests his Optics. M. Merleau-Ponty, Phénoménologie de la perception (1945); L’Œil et l’esprit (1961), part III, on Descartes’ Dioptrique; SEP “Maurice Merleau-Ponty”
Evidence: AI draft
Maurice Merleau-Ponty › 1908–1961
Hilary Putnam
criticised by
Putnam argued that the brain-in-a-vat hypothesis, a modern version of Descartes’ demon, refutes itself: envatted brains could not even refer to vats (Reason, Truth and History, 1981). H. Putnam, Reason, Truth and History (1981), ch. 1 “Brains in a Vat”; R. Descartes, Meditationes (1641), I
Evidence: AI draft
Hilary Putnam › 1926–2016
Aníbal Quijano
criticised by
Quijano traced the Eurocentric paradigm of knowledge to the Cartesian separation of a knowing subject, as reason, from its object and from the body – a dualism that in his account allowed the colonised to be classed as nature and body; critics dispute that Eurocentrism derives from Descartes. A. Quijano, “Colonialidad y modernidad/racionalidad”, Perú Indígena 13:29 (1992); “Colonialidad del poder, eurocentrismo y América Latina”, in E. Lander (ed.), La colonialidad del saber (2000)
Evidence: AI draft
Aníbal Quijano › 1928–2018
Richard Rorty
criticised by
Rorty argued that Descartes invented the mind as an inner mirror of nature, founding a philosophy centred on epistemology (Philosophy and the Mirror of Nature, 1979, ch. 1). R. Rorty, Philosophy and the Mirror of Nature (1979), ch. 1; SEP “Richard Rorty”
Evidence: AI draft
Richard Rorty › 1931–2007
Tom Regan
criticised by
Regan rejected Descartes’ denial of consciousness to animals as unfounded: many mammals are ‘subjects-of-a-life’ with beliefs, desires and inherent value (The Case for Animal Rights, 1983, ch. 1). T. Regan, The Case for Animal Rights (1983), ch. 1; R. Descartes, Discours de la méthode (1637), part V
Evidence: AI draft
Tom Regan › 1938–2017
Daniel Dennett
criticised by
Dennett attacked the ‘Cartesian Theater’, a central place in the brain where it all comes together for consciousness, surviving as ‘Cartesian materialism’ (Consciousness Explained, 1991). D. C. Dennett, Consciousness Explained (1991), ch. 5; D. C. Dennett & M. Kinsbourne, “Time and the Observer”, Behavioral and Brain Sciences 15 (1992)
Evidence: AI draft
Daniel Dennett › 1942–2024
Andy Clark
criticised by
Clark rejected the Cartesian picture of the mind as an inner, disembodied reasoner: cognition is embodied and can extend into tools and environment (Being There, 1997). A. Clark, Being There (1997); A. Clark & D. J. Chalmers, “The Extended Mind”, Analysis 58 (1998); Supersizing the Mind (2008)
Evidence: AI draft
Andy Clark › b. 1957
Thomas Metzinger
criticised by
Metzinger argued that the Cartesian intuition of an irreducible self stems from the mind’s representational structure: there are no selves, only transparent self-models (Being No One, 2003). T. Metzinger, Being No One: The Self-Model Theory of Subjectivity (2003); The Ego Tunnel (2009)
Evidence: AI draft
Thomas Metzinger › b. 1958
Brian Burkhart
criticised by
Burkhart read Descartes’ thinking I as a subject without land or culture, an example of the Western ‘delocality’ that served colonisation (Indigenizing Philosophy through the Land, 2019). B. Burkhart, Indigenizing Philosophy through the Land (2019); cf. E. Dussel, 1492: El encubrimiento del otro (1992) on ego cogito and ego conquiro
Evidence: AI draft
Brian Burkhart › contemporary
Criticizes 1
Aristotle
criticised
Descartes rejected the scholastic-Aristotelian substantial forms and real qualities, explaining nature by extension and motion and banishing final causes from physics (letter to Regius, January 1642; Meditations IV). Descartes to Regius, Jan. 1642 (AT III 491–510); Meditationes IV (AT VII 55); Principia philosophiae IV §§198–203; SEP “Descartes’ Physics”
Evidence: AI draft
Aristotle › 384–322 BCE
Works
Four rules of thought and the first “I think, therefore I am”.
Radical doubt, the cogito, proofs of God and mind–body dualism.
Position
Descartes wanted to rebuild knowledge on a foundation that could not be doubted. He doubted everything – the senses, the body, even mathematics, imagining an evil demon deceiving him – until one certainty remained: while I doubt, I think, and so I exist. From this “I think, therefore I am” he argued for God as guarantor of clear and distinct ideas, and for the reality of the external world. Mind, a thinking thing, and body, an extended thing, are two distinct substances – which raised the lasting puzzle of how they interact, a puzzle Princess Elisabeth of Bohemia pressed on him in 1643 and that he never fully solved. With analytic geometry and a mechanical physics he laid foundations for modern science; he is often called the father of modern philosophy and of rationalism.
Life & context
Born in 1596 in La Haye in Touraine, Descartes was educated by the Jesuits at La Flèche and studied law. He served as a volunteer soldier, and in 1619 had the insight that led him to a new method. He spent most of his productive life in the Dutch Republic. Invited by Queen Christina, he went to Stockholm in 1649 and died there in 1650.
Further main works
- Rules for the Direction of the Mind (c. 1628)
- Principles of Philosophy (1644)
- The Passions of the Soul (1649)
Appears in
- Journey ‘Doubt and the Self’ · Stop 3 of 10
- Journey ‘The Riddle of Consciousness’ · Stop 1 of 10
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