Editing Cogito, ergo sum (section)

== 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 language|Greek]]: νόησις νοήσεως, ''nóesis noéseos'') and [[Aristotle]] explains the idea in full length:{{blockquote|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.)
}}
The Cartesian statement was interpreted to be an Aristotelian [[syllogism]] where the premise that all thinkers are also [[being]]s is not made explicit.<ref>{{cite web|url=https://literarydevices.com/syllogism/|title=Definition of Syllogism|date=3 October 2015|archive-url=https://archive.today/20210506053835/https://literarydevices.com/syllogism/|archive-date=6 May 2021|url-status=live|access-date=6 May 2021}}</ref>

In the early fifth century AD, [[Augustine of Hippo]] in ''[[City of God (book)|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>{{cite book |title=Augustine: The City of God Against the Pagans |page=484 |url=https://archive.org/details/cityofgodagainst0000augu_p2b5/page/484/mode/2up?view=theater |url-access=registration |translator=R. W. Dyson |publisher=Cambridge University Press |date=1998}}</ref>{{efn|Augustine makes a similar argument in the ''[[Enchiridion of Augustine|Enchiridion]]'', ch. 7, sec. 20.}} This formulation ({{lang|la|si fallor, sum}}) is sometimes called the Augustinian {{lang|la|cogito}}.<ref>{{Cite book|last=Matthews|first=Gareth|title=Thought's Ego in Augustine and Descartes|chapter-url=https://www.degruyter.com/document/doi/10.7591/9781501737152-005/html|chapter=3. The Augustinian Cogito|date=2019-05-15|pages=29–38|publisher=Cornell University Press|isbn=978-1-5017-3715-2|language=en|doi=10.7591/9781501737152-005|s2cid=242208218}}</ref> In 1640, Descartes wrote to thank Andreas Colvius (a friend of Descartes's mentor, [[Isaac Beeckman]]) for drawing his attention to Augustine:

{{blockquote|I am obliged to you for drawing my attention to the passage of St Augustine relevant to my ''I am thinking, therefore I exist''. I went today to the library of this town to read it, and I do indeed find that he does use it to prove the certainty of our existence. He goes on to show that there is a certain likeness of the Trinity in us, in that we exist, we know that we exist, and we love the existence and the knowledge we have. I, on the other hand, use the argument to show that this ''I'' which is thinking is an immaterial substance with no bodily element. These are two very different things. In itself it is such a simple and natural thing to infer that one exists from the fact that one is doubting that it could have occurred to any writer. But I am very glad to find myself in agreement with St Augustine, if only to hush the little minds who have tried to find fault with the principle.<ref name="CSMK III" />{{rp|159}}}}

Another predecessor was [[Avicenna]]'s "[[Floating man|Floating Man]]" [[thought experiment]] on human [[self-awareness]] and [[self-consciousness]].<ref name="Leaman">[[Hossein Nasr|Nasr, Seyyed Hossein]], and [[Oliver Leaman]]. 1996. ''History of Islamic Philosophy''. Routledge. p. 315. {{ISBN|0-415-13159-6}}.</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">[[Sarvepalli Radhakrishnan|Radhakrishnan, Sarvepalli]]. 1948. ''Indian Philosophy'' II. [[George Allen & Unwin Ltd]]. p. 476.</ref>

Spanish philosopher [[Gómez Pereira]] in his 1554 work ''[[Gómez Pereira#The immortality of the soul|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>