Descartes used the famous phrase 'Cogito, ergo sum' to assert his existence amid doubt and pondered on the potential deception by an 'evil demon.' He established the belief in his own consciousness as the foundational basis for his reasoning.
Descartes, a renowned philosopher, utilized various arguments to doubt his beliefs. One of his most famous arguments is encapsulated in the phrase 'Cogito, ergo sum' or 'I think, therefore I am,' highlighting his certainty of his own existence even amidst doubt. Moreover, Descartes pondered on the possibility of being deceived by an 'evil demon' to cast skepticism on the validity of his senses and perceptions. Lastly, he sought to build his knowledge on a firm foundation, starting with the irrefutable belief in his own consciousness as a basis for further reasoning.
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