Rene Descartes was a French mathematician and philosopher who is considered as one of the founding fathers of modern philosophy. His quote ‘I think, therefore I am” (‘cogito ergo sum’ in Latin) is misunderstood and misinterpreted widely. Initially, this quote was written in French (Je pense, donc je suis); it is found in Discourse on the Method (1637). Then it appeared in Latin in his book ‘Principles of Philosophy’ (1644).
Even Eckhart Tolle seems to have misunderstood the true meaning of the quote. In ‘The Power of Now’, he wrote “The philosopher Descartes believed he had found the most fundamental truth when he made his famous statement: “I think, therefore I am.” He had, in fact, given expression to the most basic error: to equate thinking with Being and identity with thinking. The compulsive thinker, which means almost everyone, lives in a state of apparent separateness, in an insanely complex world of continuous problems and conflict, a world that reflects the ever-increasing fragmentation of the mind.”
Rene Descartes was not spiritually awake, as the word ‘awakening’ is used by Tolle and modern spiritual community. But certainly Descartes did not equate the thinking self with being as it has been claimed. His logic is more deeper and closer to the theme of Eckhart Tolle’s own book; it is the same logic that Advaita Vedanta uses to question the reliability of senses and the existence of external reality. I have given more details in this video.