Rene Descartes, 1596 - 1650
For many, the first thing to come to mind at the mention of Rene Descartes is the famous quote, "Cogito ergo sum", or in English, "I think, therefore I am". While this fundamental truth is exceedingly important in itself, it also represents a change in focus from questioning what the true state of the world is to what you as an individual can be certain of that bespoke a huge shift in Christianity in the medieval times. All this, Prior to Descartes’ ideas in philosophy, thinkers had chiefly looked to uncover what reality is for everyone under the implication that there exists a creator or creators who set this objective truth for us to uncover. Descartes’ new focus on critically determining what a person can be certain of puts humanity in the role of the one who decides what is true rather than any creator god. Unfortunately, Descartes held off publishing much of his work on the subject after hearing of Galileo’s fate, but the extracts, published as the famous introduction Discourse on the Method (Discours de la Métode) and 3 essays, including Geometry (La Géométrie) which was to forge his legacy in mathematics. Descartes’ Discourse changed the face of philosophy, bringing a more mathematical line of thought into philosophical arguments via four carefully-outlined rules of philosophical investigation and numerous applications of them. The entire work was published later, as well as Principles of Philosophy and Meditations on First Philosophy, the latter of which is still in wide use for university philosophy courses today.
The implications of Descartes’ works range far and wide and have done a great deal toward unifying the natural sciences, and some social science too. And all this, it is reported, came to him in a vision at the age of twenty-three when he shut himself in a stove room to fend off the cold (Caroll, 2004).
Caroll, Bradley W. "Descartes' Dream." Weber University Physics. Weber University, 26 Mar. 2004. Web. 23 Nov. 2013.