Cogito, ergo sum

File:Frans Hals - Portret van René Descartes.jpg

René Descartes, who published the phrase in Discourse on the Method, in 1637

Template:Descartes The Latin {{#invoke:Lang|lang}}, usually translated into English as "I think, therefore I am",Template:Efn is the "first principle" of René Descartes's philosophy. He originally published it in French as Template:Nowrap, Template:Nowrap in his 1637 Discourse on the Method, so as to reach a wider audience than Latin would have allowed.<ref>Template:Cite book</ref> It later appeared in Latin in his Principles of Philosophy, and a similar phrase also featured prominently in his Meditations on First Philosophy. The dictum is also sometimes referred to as the cogito.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> As Descartes explained in a margin note, "we cannot doubt of our existence while we doubt." In the posthumously published The Search for Truth by Natural Light, he expressed this insight as {{#invoke:Lang|lang}} ("I doubt, therefore I am — or what is the same — I think, therefore I am").<ref name="AT">Template:Citation.</ref><ref name="Hintikka">Template:Cite journal</ref> Antoine Léonard Thomas, in a 1765 essay in honor of Descartes presented it as {{#invoke:Lang|lang}} ("I doubt, therefore I think, therefore I am").Template:Efn

Descartes's statement became a fundamental element of Western philosophy, as it purported to provide a certain foundation for knowledge in the face of radical doubt. While other knowledge could be a figment of imagination, deception, or mistake, Descartes asserted that the very act of doubting one's own existence served—at minimum—as proof of the reality of one's own mind; there must be a thinking entity—in this case the self—for there to be a thought.

One critique of the dictum, first suggested by Pierre Gassendi, is that it presupposes that there is an "I" which must be doing the thinking. According to this line of criticism, the most that Descartes was entitled to say was that "thinking is occurring", not that "I am thinking".<ref>{{#invoke:citation/CS1|citation |CitationClass=web }} from Stanford Encyclopedia of Philosophy</ref>

In Descartes's writings

Descartes first wrote the phrase in French in his 1637 Discourse on the Method. He referred to it in Latin without explicitly stating the familiar form of the phrase in his 1641 Meditations on First Philosophy. The earliest written record of the phrase in Latin is in his 1644 Principles of Philosophy, where, in a margin note (see below), he provides a clear explanation of his intent: "[W]e cannot doubt of our existence while we doubt". Fuller forms of the phrase are attributable to other authors.

Discourse on the Method

The phrase first appeared (in French) in Descartes's 1637 Discourse on the Method in the first paragraph of its fourth part:

Meditations on First Philosophy

In 1641, Descartes published (in Latin) Meditations on first philosophy in which he referred to the proposition, though not explicitly as "cogito, ergo sum" in Meditation II:

In Response to an Objection from Marin Mersenne, he wrote "cogito, ergo sum” in an extended form and, again, prefaced with ‘ego’:

Principles of Philosophy

In 1644, Descartes published (in Latin) his Principles of Philosophy which begins {{#invoke:Lang|lang}} (That in order to seek truth, it is necessary once in the course of our life, to doubt, as far as possible, of all things.Template:Efn) The phrase "ego cogito, ergo sum" appears in Part 1, article 7:

File:1644 Principia Philosophae.jpg

"ego cogito, ergo sum" with margin note in original (1644) Principia Philosophae

Descartes's margin note for the above paragraph is:

The Search for Truth by Natural Light

Descartes, in a lesser-known posthumously published work written ca. 1647,<ref>Template:Citation</ref> originally in French with the title {{#invoke:Lang|lang}} (The Search for Truth by Natural Light)<ref name="AT" /> and later in Latin with the title {{#invoke:Lang|lang}},<ref>Template:Cite book</ref> provides his only known phrasing of the cogito as {{#invoke:Lang|lang}} and admits that his insight is also expressible as dubito, ergo sum:<ref name="Hintikka"/>

File:Dubito, ergo sum.jpg

"dubito, ergo sum, vel, quod idem est, cogito, ergo sum" in Inquisitio Veritatis per Lumen Naturale

"{{#invoke:Lang|lang}}" or "{{#invoke:Lang|lang}}"?

Peter J. Markie notes: "Descartes stresses the first person in his premise twice in the Principles and once in his Reply to Mersenne. {{#invoke:Lang|lang}} . . . . (AT VIII, 7; AT VIII, 8; AT VII, 140)" and adds "It is unlikely that Descartes would stress the first person in his premise, if he wanted us to read the premise as 'Thought is taking place' rather than 'I think.'"<ref>Template:Cite journal</ref> Gary Hatfield writes: "[I]n Latin the first-person voice need not be expressed through a separate pronoun, but may be included in the verb form; nonetheless, Descartes used the Latin first-person pronoun {{#invoke:Lang|lang}} more than thirty times in the six Meditations."<ref>Template:Cite book</ref>

Other forms

The proposition is sometimes given as {{#invoke:Lang|lang}}. This form was penned by the French literary critic, Antoine Léonard Thomas,Template:Efn in an award-winning 1765 essay in praise of Descartes, where it appeared as "{{#invoke:Lang|lang}}" ('Since I doubt, I think; since I think, I exist'). With rearrangement and compaction, the passage translates to "I doubt, therefore I think, therefore I am," or in Latin, "dubito, ergo cogito, ergo sum."Template:Efn This aptly captures Descartes's intent as expressed in his posthumously published La Recherche de la Vérité par La Lumiere Naturale as noted above: I doubt, therefore I am — or what is the same — I think, therefore I am.

A further expansion, {{#invoke:Lang|lang}} ("…—a thinking thing") extends the cogito with Descartes's statement in the subsequent Meditation, {{#invoke:Lang|lang}} ("I am a thinking [conscious] thing, that is, a being who doubts, affirms, denies, knows a few objects, and is ignorant of many, [who loves, hates,]Template:Efn wills, refuses, who imagines likewise, and perceives").Template:Efn This has been referred to as "the expanded cogito."<ref name=Kline1967 />Template:Efn

Translation

"I am thinking" vs. "I think"

While the Latin cōgitō may be translated rather easily as "I think/ponder/visualize", Template:Nowrap does not indicate whether the verb form corresponds to the English simple present ("think") or progressive aspect ("is thinking").<ref>Template:Cite book</ref> Following John Lyons (1982),<ref>Template:Cite book</ref> Vladimir Žegarac notes, "The temptation to use the simple present is said to arise from the lack of progressive forms in Latin and French, and from a misinterpretation of the meaning of cogito as habitual or generic" (cf. gnomic aspect).<ref>Template:Cite thesis</ref> Also following Lyons, Ann Banfield writes, "In order for the statement on which Descartes's argument depends to represent certain knowledge,… its tense must be a true present—in English, a progressive,… not as 'I think' but as 'I am thinking, in conformity with the general translation of the Latin or French present tense in such nongeneric, nonstative contexts."<ref>Template:Cite journal</ref> Or in the words of Simon Blackburn, "Descartes's premise is not 'I think' in the sense of 'I ski', which can be true even if you are not at the moment skiing. It is supposed to be parallel to 'I am skiing'."<ref name=Blackburn1999>Template:Cite book</ref>

The similar translation "I am thinking, therefore I exist" of Descartes's correspondence in French ("Template:Nowrap, Template:Nowrap") appears in The Philosophical Writings of Descartes by Cottingham et al. (1988).<ref name="CSMK III" />Template:Rp

The earliest known translation as "I am thinking, therefore I am" is from 1872 by Charles Porterfield Krauth.<ref name=Krauth>Template:Cite journal</ref>Template:Efn

Fumitaka Suzuki writes "Taking consideration of Cartesian theory of continuous creation, which theory was developed especially in the Meditations and in the Principles, we would assure that 'I am thinking, therefore I am/exist' is the most appropriate English translation of 'ego cogito, ergo sum'."<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

"I exist" vs. "I am"

Alexis Deodato S. Itao notes that {{#invoke:Lang|lang}} is "literally 'I think, therefore I am'."<ref>Template:Cite journal</ref> Others differ: 1) "[A] precise English translation will read as 'I am thinking, therefore I exist';<ref>Template:Cite thesis</ref> and 2) "[S]ince Descartes ... emphasized that existence is such an important 'notion,' a better translation is 'I am thinking, therefore I exist.'"<ref>Template:Cite thesis</ref>

Punctuation

Descartes wrote this phrase as such only once, in the posthumously published lesser-known work noted above, The Search for Truth by Natural Light.<ref name="AT" /> It appeared there mid-sentence, uncapitalized, and with a comma. (Commas were not used in Classical LatinTemplate:Efn but were a regular feature of scholastic Latin,<ref>Template:Cite book</ref> the Latin Descartes "had learned in a Jesuit college at La Flèche.")<ref>Template:Cite book</ref> Most modern reference works show it with a comma, but it is often presented without a comma in academic work and in popular usage. In Descartes's Principia Philosophiae, the proposition appears as ego cogito, ergo sum.<ref name="Descartes1644">Template:Cite book</ref>

Interpretation

As put succinctly by Krauth (1872), "That cannot doubt which does not think, and that cannot think which does not exist. I doubt, I think, I exist."<ref name=Krauth />

The phrase cogito, ergo sum is not used in Descartes's Meditations on First Philosophy, but the term "the cogito" is used to refer to an argument from it. In the Meditations, Descartes phrases the conclusion of the argument as "that the proposition, I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind" (Meditation II). George Henry Lewes says Descartes "has told us that [his objective] was to find a starting point from which to reason—to find an irreversible certainty. And where did he find this? In his own consciousness. Doubt as I may, I cannot doubt of my own existence, because my very doubts reveal to me a something which doubts. You may call this an assumption, if you will; I point out the fact as one above and beyond all logic; which logic can neither prove nor disprove; but which must always remain an irreversible certainty, and as such a fitting basis of philosophy."<ref>Template:Cite book</ref>

At the beginning of the second meditation, having reached what he considers to be the ultimate level of doubt—his argument from the existence of a deceiving god—Descartes examines his beliefs to see if any have survived the doubt. In his belief in his own existence, he finds that it is impossible to doubt that he exists. Even if there were a deceiving god (or an evil demon), one's belief in their own existence would be secure, for there is no way one could be deceived unless one existed in order to be deceived.

But I have convinced myself that there is absolutely nothing in the world, no sky, no earth, no minds, no bodies. Does it now follow that I, too, do not exist? No. If I convinced myself of something [or thought anything at all], then I certainly existed. But there is a deceiver of supreme power and cunning who deliberately and constantly deceives me. In that case, I, too, undoubtedly exist, if he deceives me; and let him deceive me as much as he can, he will never bring it about that I am nothing, so long as I think that I am something. So, after considering everything very thoroughly, I must finally conclude that the proposition, I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind. (AT VII 25; CSM II 16–17)Template:Efn

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There are three important notes to keep in mind here. First, he claims only the certainty of his own existence from the first-person point of view — he has not proved the existence of other minds at this point. This is something that has to be thought through by each of us for ourselves, as we follow the course of the meditations. Second, he does not say that his existence is necessary; he says that if he thinks, then necessarily he exists (see the instantiation principle). Third, this proposition "I am, I exist" is held true not based on a deduction (as mentioned above) or on empirical induction but on the clarity and self-evidence of the proposition. Descartes does not use this first certainty, the cogito, as a foundation upon which to build further knowledge; rather, it is the firm ground upon which he can stand as he works to discover further truths.<ref>Self, Reason, and Freedom: A New Light on Descartes' Metaphysics Andrea Christofidou; chapter 2</ref> As he puts it:

Archimedes used to demand just one firm and immovable point in order to shift the entire earth; so I too can hope for great things if I manage to find just one thing, however slight, that is certain and unshakable. (AT VII 24; CSM II 16)Template:Efn{{#if:|{{#if:|}}

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According to many Descartes specialists, including Étienne Gilson, the goal of Descartes in establishing this first truth is to demonstrate the capacity of his criterion — the immediate clarity and distinctiveness of self-evident propositions — to establish true and justified propositions despite having adopted a method of generalized doubt. As a consequence of this demonstration, Descartes considers science and mathematics to be justified to the extent that their proposals are established on a similarly immediate clarity, distinctiveness, and self-evidence that presents itself to the mind. The originality of Descartes's thinking, therefore, is not so much in expressing the cogito—a feat accomplished by other predecessors, as we shall see—but on using the cogito as demonstrating the most fundamental epistemological principle, that science and mathematics are justified by relying on clarity, distinctiveness, and self-evidence. Baruch Spinoza in "Principia philosophiae cartesianae" at its Prolegomenon identified "cogito ergo sum" the "ego sum cogitans" (I am a thinking being) as the thinking substance with his ontological interpretation.

Predecessors

Although the idea expressed in cogito, ergo sum is widely attributed to Descartes, he was not the first to mention it. In the late sixth or early fifth century BC, Parmenides is quoted as saying "For to be aware and to be are the same". (Fragment B3) Plato spoke about the "knowledge of knowledge" (Greek: νόησις νοήσεως, nóesis noéseos) and Aristotle explains the idea in full length:

But if life itself is good and pleasant…and if one who sees is conscious that he sees, one who hears that he hears, one who walks that he walks and similarly for all the other human activities there is a faculty that is conscious of their exercise, so that whenever we perceive, we are conscious that we perceive, and whenever we think, we are conscious that we think, and to be conscious that we are perceiving or thinking is to be conscious that we exist... (Nicomachean Ethics, 1170a 25 ff.)

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The Cartesian statement was interpreted to be an Aristotelian syllogism where the premise that all thinkers are also beings is not made explicit.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

In the early fifth century AD, Augustine of Hippo in De Civitate Dei (book XI, 26) affirmed his certain knowledge of his own existence, and added: "So far as these truths are concerned, I do not at all fear the arguments of the Academics when they say, What if you are mistaken? For if I am mistaken, I exist."<ref>Template:Cite book</ref>Template:Efn This formulation ({{#invoke:Lang|lang}}) is sometimes called the Augustinian {{#invoke:Lang|lang}}.<ref>Template:Cite book</ref> In 1640, Descartes wrote to thank Andreas Colvius (a friend of Descartes's mentor, Isaac Beeckman) for drawing his attention to Augustine:

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Another predecessor was Avicenna's "Floating Man" thought experiment on human self-awareness and self-consciousness.<ref name="Leaman">Nasr, Seyyed Hossein, and Oliver Leaman. 1996. History of Islamic Philosophy. Routledge. p. 315. Template:ISBN.</ref>

The 8th century Hindu philosopher Adi Shankara wrote, in a similar fashion, that no one thinks 'I am not', arguing that one's existence cannot be doubted, as there must be someone there to doubt.<ref name="Radhakrishnan.S">Radhakrishnan, Sarvepalli. 1948. Indian Philosophy II. George Allen & Unwin Ltd. p. 476.</ref>

Spanish philosopher Gómez Pereira in his 1554 work Antoniana Margarita, wrote "nosco me aliquid noscere, & quidquid noscit, est, ergo ego sum" ('I know that I know something, anyone who knows is, therefore I am').<ref>Pereira, Gómez. [1554] 1749. Antoniana Margarita: "De Immortalitate Animae". p. 277.</ref><ref>López, Modesto Santos. 1986. "Gómez Pereira, médico y filósofo medinense." In Historia de Medina del Campo y su Tierra, volumen I: Nacimiento y expansión, edited by E. L. Sanz.</ref>

Critique

Use of "I"

In Descartes, The Project of Pure Enquiry, English philosopher Bernard Williams provides a history and full evaluation of this issue.<ref name=":1" /> The first to raise the "I" problem was Pierre Gassendi, who in his {{#invoke:Lang|lang}},<ref>Template:Cite book</ref> as noted by Saul Fisher, "points out that recognition that one has a set of thoughts does not imply that one is a particular thinker or another. …[T]he only claim that is indubitable here is the agent-independent claim that there is cognitive activity present."<ref>Fisher, Saul. [2005] 2013. "Pierre Gassendi" (revised ed.). Stanford Encyclopedia of Philosophy. Retrieved 17 June 2020.</ref>

The objection, as presented by Georg Lichtenberg, is that rather than supposing an entity that is thinking, Descartes should have said: "thinking is occurring." That is, whatever the force of the cogito, Descartes draws too much from it; the existence of a thinking thing, the reference of the "I," is more than the cogito can justify. Friedrich Nietzsche criticized the phrase in that it presupposes that there is an "I", that there is such an activity as "thinking", and that "I" know what "thinking" is. He suggested a more appropriate phrase would be "it thinks" wherein the "it" could be an impersonal subject as in the sentence "It is raining."<ref name="thinkingisoccurring">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Søren Kierkegaard

The Danish philosopher Søren Kierkegaard called the phrase a tautology in his Concluding Unscientific Postscript.<ref name=":0" />Template:Rp He argues that the cogito already presupposes the existence of "I", and therefore concluding with existence is logically trivial. Kierkegaard's argument can be made clearer if one extracts the premise "I think" into the premises "'x' thinks" and "I am that 'x'", where "x" is used as a placeholder in order to disambiguate the "I" from the thinking thing.<ref>Schönbaumsfeld, Genia. A Confusion of the Spheres. Oxford, 2007. p. 168-170.</ref>

Here, the cogito has already assumed the "I"'s existence as that which thinks. For Kierkegaard, Descartes is merely "developing the content of a concept", namely that the "I", which already exists, thinks.<ref name=":0">Kierkegaard, Søren. [1844] 1985. Philosophical Fragments, translated by P. Hong.</ref>Template:Rp As Kierkegaard argues, the proper logical flow of argument is that existence is already assumed or presupposed in order for thinking to occur, not that existence is concluded from that thinking.<ref>Archie, Lee C. 2006. "Søren Kierkegaard, 'God's Existence Cannot Be Proved'." In Philosophy of Religion. Lander Philosophy.</ref>

Bernard Williams

Williams himself claimed that what we are dealing with when we talk of thought, or when we say "I am thinking," is something conceivable from a third-person perspective—namely objective "thought-events" in the former case, and an objective thinker in the latter. He argues, first, that it is impossible to make sense of "there is thinking" without relativizing it to something. However, this something cannot be Cartesian egos, because it is impossible to differentiate objectively between things just on the basis of the pure content of consciousness. The obvious problem is that, through introspection, or our experience of consciousness, we have no way of moving to conclude the existence of any third-personal fact, to conceive of which would require something above and beyond just the purely subjective contents of the mind.<ref name=":1">Template:Cite book</ref>

Martin Heidegger

As a critic of Cartesian subjectivity, German philosopher Martin Heidegger sought to ground human subjectivity in death as that certainty which individualizes and authenticates our Being (Dasein). As he wrote in 1925 in History of the Concept of Time:<ref>Template:Cite book</ref>

This certainty, that "I myself am, in that I will die," is the basic certainty of Dasein itself. It is a genuine statement of Dasein, while cogito sum is only the semblance of such a statement. If such pointed formulations mean anything at all, then the appropriate statement pertaining to Dasein in its being would have to be sum moribundus [I am in dying], moribundus not as someone gravely ill or wounded, but insofar as I am, I am moribundus. The MORIBUNDUS first gives the SUM its sense.{{#if:|{{#if:|}}

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John Macmurray

The Scottish philosopher John Macmurray rejected the cogito outright in order to place action at the center of a philosophical system he entitled the Form of the Personal. "We must reject this, both as standpoint and as method. If this be philosophy, then philosophy is a bubble floating in an atmosphere of unreality."<ref>Macmurray, John. 1991. The Self as Agent. Humanity Books. p. 78.</ref> The reliance on thought creates an irreconcilable dualism between thought and action in which the unity of experience is lost, thus dissolving the integrity of our selves and destroying any connection with reality. In order to formulate a more adequate cogito, Macmurray proposes the substitution of "I do" for "I think," ultimately leading to a belief in God as an agent to whom all persons stand in relation.

Alfred North Whitehead

In Process and Reality, Whitehead wrote "Descartes in his own philosophy conceives the thinker as creating the occasional thought. The philosophy of organism inverts the order, and conceives the thought as a constituent operation in the creation of the occasional thinker. The thinker is the final end whereby there is the thought. In this inversion we have the final contrast between a philosophy of substance and a philosophy of organism."<ref>Template:Cite book</ref>

In popular culture

In the short story, I Have No Mouth, and I Must Scream, by Harlan Ellison, Gorrister, when asked what 'AM' means, says "At first it meant Allied Mastercomputer, and then it meant Adaptive Manipulator, and later on it developed sentience and linked itself up and they called it an Aggressive Menace, but by then it was too late, and finally called itself AM, emerging intelligence, and what it meant was I am ... cogito ergo sum ... I think, therefore I am."<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

In the Japanese animated television series, Ergo Proxy, a computer virus that effects the autoreivs, the series' version of robots, known as the Cogito virus begins infecting the autoreivs, which is named such due to the fact that it makes the infected conscious, and experience emotions as a human would.

In Monty Python's Bruces' Philosophers Song, one of the lyrics jokingly quotes Descarte's axiom as "I drink therefore I am."<ref>Template:Citation</ref>

In the episode "Work Experience" of The Office, David Brent says, "We are the most efficient branch, cogito ergo sum, we'll be fine."<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

In the video game Honkai: Star Rail, Dr. Ratio (real name Veritas Ratio), a playable character and, according to in-game lore, a philosopher,<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> has a skill, named "Cogito, Ergo Sum".

See also

• Cartesian doubt
• Floating man
• Apperception
• Academic skepticism
• Be, and it is
• Brain in a vat
• I Am that I Am
• Tat Tvam Asi, "You are that"
• The Animal That Therefore I Am
• Vertiginous question

Further reading

• Abraham, W. E. 1974. "Disentangling the Cogito." Mind 83:329.
• Baird, Forrest E., and Walter Kaufmann. 2008. From Plato to Derrida. Upper Saddle River, NJ: Pearson Prentice Hall. Template:ISBN.
• Boufoy-Bastick, Z. 2005. "Introducing 'Applicable Knowledge' as a Challenge to the Attainment of Absolute Knowledge." Sophia Journal of Philosophy 8:39–52.
• Christofidou, A. 2013. Self, Reason, and Freedom: A New Light on Descartes' Metaphysics. Routledge.
• Hatfield, G. 2003. Routledge Philosophy Guidebook to Descartes and the Meditations. Routledge. Template:ISBN.
• Kierkegaard, Søren. [1844] 1985. Philosophical Fragments. Princeton. Template:ISBN.
• — [1846] 1985. Concluding Unscientific Postscript. Princeton. Template:ISBN.

External links

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