René Descartes' Meditations on the First PhilosophyRené Descartes laid the foundations of 17th-century rationalism, a view opposed by the empiricist school of thought. As a rationalist, Descartes strongly believed in reason as the primary source of knowledge. He favored deduction and the intellect over the senses, and for this reason he found no comfort in believing that the opinions he had developed in his youth were credible. It is for this reason that René Descartes chose to “raze everything and start again from the original foundations” (13). On page thirteen of his Meditations on Early Philosophy, Descartes asserted that these opinions of his youth were false and, therefore, the opinions he had built upon them were also false. In this book, Descartes claims to have freed his mind from all these false opinions and begins by believing nothing, because he is trying to obtain an objective view of the truth, which he cannot do if he is influenced by his pass. misconceptions. On page fourteen, just before nineteen in the margins, Descartes discusses the deceptive nature of the senses. He claims that "everything that I had accepted until now as the most true, I received either from the senses or through the senses" (14), and because Descartes believes that one should never proud of anything that has deceived us even once (14), he concludes that he cannot trust anything that he has considered true until now. It is Descartes' reasoning that casts doubt on everything he thought he knew, and from this conclusion he arrives at the only absolute certainty that he exists. To arrive at this certainty, he first mentions that to determine that we know anything...... middle of paper ......ng, and thinking implies existence. Therefore, he has discovered one undoubted belief so far: that he exists. In Mediation III, he proves the existence of God as another indubitable idea with his first two arguments for the existence of God, and again with his third argument in Mediation V. He goes on to establish the possibility of acquire knowledge of the world based on deduction and perception, creating an unshakable ground on which all other knowledge can be founded. A final conclusion that Descartes arrives at is that it is acceptable to believe that our senses communicate precise information to our brains, provided that we apply our intellect and deductive reasoning to that information. Therefore, it arrives at a set of fundamental principles that can be known to be true without doubt, and acquires a solid foundation for true knowledge..