"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 very 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 one can doubt everything except their own thoughts, Descartes argued that self-awareness and consciousness are undeniable evidence of being. This idea has influenced various fields, including philosophy, psychology, and cognitive science.