Descartes firmly believed that reason is a native gift of humans, and that true knowledge can be directly gleaned not from books but only through the methodical application of reason. The expressed aim of many of his books was to present complex scientific and philosophical matters in such a way that the least sophisticated readers could understand them. Because Descartes believed that every human possesses the “natural light” of reason, he believed that if he presented all his arguments as logical trains of thought, then anyone could understand them, and nobody could help but be swayed.

In the original edition of Discourse on Method, in fact, Descartes declares his aim with the subtitle “In which the Author… explains the most abstruse Topics he could choose, and does so in such a way that even persons who have never studied can understand them.” In an attempt to reach a wider audience, Descartes occasionally wrote in French, the language of his countrymen, rather than Latin, the language of scholars, so that people without a formal education could understand him.