I think, therefore I am

== English == === Alternative forms === I think; therefore, I am; I think; therefore I am; I think therefore I am === Etymology === Calque of French je pense, donc je suis or perhaps of Latin cōgitō, ergō sum. First written in French by René Descartes, a 17th century French philosopher, in Discourse on the Method (1637) as je pense donc je suis, which he later expressed in Latin in Principles of Philosophy (1644). === Pronunciation === === Phrase === I think, therefore I am (philosophy) I am able to think, therefore I exist; a proof of existence based on the fact that someone capable of any form of thought necessarily exists. ==== Usage notes ==== Subject to many humorous variations, such as I drink, therefore I am; I speak, therefore I am; or I shop, therefore I am. ==== Translations ==== ==== Further reading ==== I think, therefore I am on Wikipedia.Wikipedia