Cogito, ergo sum relying on clarity, distinctiveness, and self-evidence. Baruch Spinoza in ""Principia philosophiae cartesianae"" at its "Prolegomenon" identified "cogito ergo sum" the ""ego sum cogitans"" (I am a thinking being) as the thinking substance with his ontological interpretation. It can also be considered that "Cogito ergo sum" is needed before any living being can go further in life". Although the idea expressed in "cogito, ergo sum" is widely attributed to Descartes, he was not the first to mention it. Plato spoke about the "knowledge of knowledge" (Greek νόησις νοήσεως "nóesis noéseos") and Aristotle explains the idea in full length: But if life
Descartes number Descartes number In number theory, a Descartes number is an odd number which would have been an odd perfect number, if one of its composite factors were prime. They are named after René Descartes who observed that the number would be an odd perfect number if only were a prime number, since the sum-of-divisors function for would satisfy, if 22021 were prime, where we ignore the fact that reveals that 22021 is composite. A Descartes number is defined as an odd number where and are coprime and , whence is taken as a 'spoof' prime. The example given is the