"Cogito, ergo sum" is a Latin phrase that translates to "I think, therefore I am." It was coined by the philosopher René Descartes in the 17th century as a fundamental element of his philosophy. Descartes used this statement to establish a foundation for knowledge, asserting that the act of thinking is proof of one's existence. The phrase emphasizes the importance of doubt and questioning in the pursuit of truth. By recognizing that the very act of thinking confirms one's existence, Descartes aimed to demonstrate that knowledge begins with self-awareness and rational thought, laying the groundwork for modern philosophy.