Identify the author of the following passage: "but what am i? a thinking being. what is a thinking being? it is a being which doubts, which understands, which conceives, which affirms . ."

Rene Descartes

Explanation:

Rene Descartes (31 March 1596 – 11 February 1650) was a French philosopher, scientist, and mathematician.  

Descartes determined a single first principle: I think.

In Discourse on the Method and Principles of Philosoph is explained like this : "Thought cannot be separated from me, therefore, I exist".

This is known as cogito ergo sum (in English: "I think, therefore I am").

Descartes concluded that, if he doubted, then, something or someone must be doing the doubting, therefore the fact that he doubted proved his existence.

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