«I think therefore I am» in latin «Cogito ergo Sum»
The french philosopher and mathematician Rene Descartes (1596-1650) is who famously first said that quote.
The meaning of I think therefore I am
It summarizes his intellectual and philosophical process that states that the only way to find the truth is through reason.
Descartes tried to establish an evident truth by means of a deductive system. He sustained that the cogito or thought, which are all the conscious acts of the spirit, always implies doubt.
Doubting everything, according to Descartes, is only a methodological procedure to find an undoubted truth. Therefore it is a methodical doubt and not a definitive mental posture.
Thanks to the criterion of doubt begins to doubt everything but could not escape the recurrent doubt that «is hesitating». So the only question that can not be removed is the doubt itself.
Descartes then comes to the conclusion that if it is not possible to eliminate the doubt, at least he can not doubt that he thinks he is doubting.
Therefore «I think» would lead to two unique conclusions: first I think and then I exist.
The evidence of Descartes on the indubitability of which I doubt because I think and because I am, would result in the famous phrase «I think, therefore I exist». He said the quote first in his book «Speech of the Method». He wrote it in the year 1637 in Leiden, Holland.
Rene Descartes believed that the common opinion and experience of humanity were not reliable to seek the truth. So he decided to devise a new system that could get rid of them.
Descartes then created a method that involved a mathematical instrument of pure deduction. It derives from an absolute reason projecting the idea of a mechanistic universe. Everything functions as a mechanism.
Rene Descartes went even further with his philosophical inquiries of reason. He stated that, although we all have a mind and a body, the only certainty is the existence of the mind (thought, reason). It is because you can not be sure or that our body exists.