Descartes opens chapter one of his "Discourse on the Method" (titled: "Various Considerations Touching the Sciences") with an assertion of the equality in all men's capacity for rational thought. All men, according to Descartes, Posses an ability for rational judgment, an ability not denied by the various forms in which they utilize it. The reason we have different judgments and opinions presented by different people is the different application of our intellect. The question to be asked by Descartes is what is, then, the proper application of human rationality that will ensure the best possible judgments of the world? The answer that Descartes offers is that of method, a method he devised as a guideline, a form to be applied on the contents of our thought process.
Part 1 of Descartes' "Discourse on Method" is full of autobiographical descriptions. Descartes says that he has received very fine education that promised to provide him with knowledge of everything important. But Descartes recalls that the more he learned the more he became full of doubts, and that the more he acquired knowledge the more he was made aware of his own ignorance. Concluding that few if any men were given a better opportunity to find the truth than the one he had, which means that this truth is in fact absent from his time. Descartes accounts how none of the things he has learned, despite being very useful in other regards, has provided him with the fundamental understanding of the words that he has sought.
Therefore, to conclude chapter 1 of his "Discourse on Method", Descartes decides not to study any longer and to abandon the things he has already learned which only prevent him from seeking true knowledge. Based on the initial proposition regarding the rational capacity of all men, Descartes decides that instead of relying on his schooling he must rely on his reason.
See additional summaries on Descartes' "Discourse on the Method":
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