Cartesianism

Cartesianism represents the ideals of the 17th century Philosopher and Mathematician Rene Descartes. It has been called "the father of modern philosophy" due to it's innovative methodological doubt.

Epistemology and Metaphysics
Descartes thinks that at least once in our life, we must doubt nearly everything we know, in order to arrive at certain knowledge. He thinks that we can doubt Nearly everything, our scenes, the existence of God, even the truth of mathematics. However, the one thing we can not doubt is that we are thinking thing that exists, or that "I think therefor I am."

From this, he argues that God must exist. Descartes defines God as a perfect being. But Descartes himself perceives that he must be an imperfect being, having believed many different contradictory things. He also perceives that either he must have come up with the idea of God, or God must have an existence outside of him, in other words, he must be real. Because a perfect thing can not come form something imperfect, God must exist.

Because God is more perfect then us, he would not allow us to be deceived, we must therefor be able to trust all clear and distinct perceptions, including our senses. Thus, our senses never lie to us, but it is only our will which fails us, in being to hasty to judge appearance to be reality.

Philosophy of Mind and Science
Descartes is duelist, who thinks the world is made up of two parts, the nonphysical world that contains things that last forever, God, human minds, ideas, the laws of mathematics and nature; and the physical world, which is made up of matter. He thinks that only humans have minds, and that animals are therefor incapable of feeling anything, including pain.

This leads to a rejection of the Aristotelian view of nature, which practices a more hylomorphic style of dualism where the mental and nonphysical are bound together much more closely, to the  point of inseparability, and which believes in teleological ideas of final causes as opposed to a world run by mechanistic laws of nature.

Ethics and Political Philosophy
Descartes didn't speak often on ethics or political philosophy. In terms of ethics, this was because he wanted to have a more cretin foundation in Metaphysics before he really got started building an ethical system. He refrained from speaking on politics becuse he thought such things should be mostly dealt with by Kings and those who they appointed as magistrates.

None the less, he did have some ideas in these two subjects, tending towards a version Virtue Ethics based on  Stoicism as well as viewing   as the natural order of things.

Personality
Descartes is an introverted and pensive, but also kindhearted and friendly ball, who is very interested in a wide variety of subjects such as science, math, and philosophy. He can generally be found writing, contemplating the mysteries of the universe, giving out free medical treatment, or performing some kind of experiment.