René Descartes' Meditations on First PhilosophyRene Descartes laid the foundations for seventeenth-century rationalism, the opposite view from the empiricist school of thought. As a rationalist, Descartes firmly believed in reason as the main source of knowledge. He favored deduction and intellect over the senses and for this reason he found no comfort in believing that his opinions, developed in his youth, were credible. It is for this reason that Renato Descartes chose to "raze everything to the ground and start again from the original foundations" (13). On page thirteen of his Meditations on Early Philosophy, Descartes stated that these opinions of his youth were false, and therefore those opinions which he had constructed upon them were also false. In this book Descartes claims to have freed his mind from all those false opinions and begins by not believing anything, because he is trying to obtain an objective vision of the truth, which he cannot do if he lets himself be influenced by his previous ideas. wrong ideas. On page fourteen, just before the nineteen mark in the margin, Descartes discusses the deceptive nature of the senses. He states that "everything that up to now I have admitted as truest I have received either from the senses or through the senses" (14), and since Descartes believes that we should never put our trust in something that has deceived us not even once time (14), he concludes that he cannot trust anything that he has believed to be true so far. This is Descartes' reasoning that leads one to doubt everything he once thought he knew, and from this conclusion he arrives at the only absolute certainty that exists. To get to this certainty, first mention that to determine that we know anything…half of the paper…and thought implies existence. Therefore, so far he has discovered an indubitable belief: that it exists. In Mediation III he demonstrates the existence of God as another indubitable idea with his first two arguments for the existence of God, and yet another time with the third argument in Mediation V. He goes on and establishes the possibility of acquiring knowledge of the world based on deduction and perception, creating an unshakable ground on which all other knowledge can rest. A final conclusion Descartes reaches is that it is acceptable to trust our senses to communicate accurate information to our brains, as long as we apply our intellect and deductive reasoning to that information. Thus, he arrives at a fundamental set of principles that can be recognized as true without any doubt and acquires a solid basis for authentic knowledge..