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Cogito, ergo sum

philosophy religion Maturity 13-18 Next article →

The phrase "cogito, ergo sum" is a fundamental principle in Western philosophy. It is most commonly translated into English as "I think, therefore I am." This idea belongs to the French scientist and philosopher René Descartes.

Frans Hals - Portret van René Descartes
Frans Hals - Portret van René Descartes

The phrase is often called "the cogito." Descartes used this principle to establish a certain foundation for human knowledge. He wanted to find a truth that could not be shaken by doubt. This concept remains a major topic in the study of how we know things.

Descartes developed this idea through a process of radical doubt. He examined his beliefs to see if any were absolutely certain. He considered whether his senses could be deceived or if he was dreaming. He even imagined a deceiving god might be tricking his mind. However, he discovered a limit to this doubt. Even if a deceiving force existed, there must be a person to be deceived. The very act of doubting requires a thinking entity to perform the doubt. Therefore, the existence of the mind is proven by the presence of thought.

Descartes expressed this insight in several different ways across his writings. He first published the idea in French in his 1637 work, "Discourse on the Method." He chose French to reach a wider audience than Latin would allow. In 1641, he published "Meditations on First Philosophy" in Latin. While he did not use the exact phrase there, he discussed the same conclusion. In 1644, he published "Principles of Philosophy," where the Latin phrase "ego cogito, ergo sum" appears.

1644 Principia Philosophae
1644 Principia Philosophae

He even added a margin note explaining that one cannot doubt existence while doubting.

There are different versions and expanded forms of this famous dictum. In a posthumously published work called "The Search for Truth by Natural Light," Descartes wrote "dubito, ergo sum." This means "I doubt, therefore I am." He noted that this was the same as saying "I think, therefore I am."

Dubito, ergo sum
Dubito, ergo sum

In 1765, Antoine Léonard Thomas wrote an essay that expanded the idea. He presented it as "I doubt, therefore I think, therefore I am." Some also refer to an "expanded cogito." This version includes the idea that the self is a "thinking thing" that also loves, hates, and perceives.

Scholars often debate the most accurate way to translate the original Latin. The word "cogito" can mean "I think" or "I am thinking." Some experts, like Ann Banfield, argue that "I am thinking" is a better translation. They believe the phrase refers to an action happening in the present moment. Others suggest that "I exist" is a more precise translation than "I am." This is because Descartes placed great importance on the concept of existence. The earliest known English translation as "I am thinking, therefore I am" appeared in 1872.

Not everyone agreed with Descartes's specific phrasing of the idea. A critic named Pierre Gassendi suggested a different interpretation. He argued that Descartes assumed too much by using the word "I." According to this critique, the phrase should only claim that "thinking is occurring." This view suggests we cannot prove there is a specific "self" doing the thinking. Despite these critiques, the cogito remains a central part of philosophical debate. It forces thinkers to question the relationship between the mind and the self.

Descartes used the cogito to justify other ways of finding truth. He believed that science and mathematics are valid if they rely on clarity. He looked for ideas that were "clear and distinct" in the mind. This method helped him build a system of knowledge based on self-evident truths. His work influenced later thinkers like Baruch Spinoza. Spinoza interpreted the cogito as the existence of a "thinking substance." The cogito serves as a starting point for understanding the connection between thought and reality.

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File:Frans Hals - Portret van René Descartes.jpg
Frans Hals - Portret van René Descartes.jpg
File:1644_Principia_Philosophae.jpg
1644_Principia_Philosophae.jpg
File:Dubito,_ergo_sum.jpg
Dubito,_ergo_sum.jpg
File:Billie Eilish - Therefore I Am.png
Billie Eilish - Therefore I Am.png
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