In chapter 2 of his "Discourse on the Method" (titled: "The principal rules of the Method which the Author has discovered") René Descartes starts to build his scientific method of thought. After describing in part 1 of Discourse on the Method how his travels has led him to doubt, Descartes now describes how he found himself in a well-heated room withdrawn from the world. This led Descartes to ponder the achievements of the individual compared with that of collectives, reasoning that the former are better than the latter (God, for example, is an individual who created great things). The purest form of thought, Descartes argues, in the one conducted alone.
In order to implement this line of thought Descartes decides to abandon everything he has learned from other people in order to remain with what only his own reason can tell him.
In order to insure the validity of his reasoning, Descartes devices a method build on four principles that will serve as guidelines for his inquiry:
1. not to accept anything as true unless it is clearly evident.
2. To simplify the inquiry by dividing any problem into the smallest possible parts.
3. To start with the simplest questions and move on to the more difficult ones.
4. To be circumspect and self-critical by constantly reviewing and reevaluating the conclusions.
This is not only the basis for Descartes' later considerations in "Discourse on the Method" and "Meditations on the First Philosophy", but can also be considered as the first basic maxims of modern scientific thought and practice. In chapter 3 of the book Descartes will add a few more rules and moral codes that will direct and give form to his philosophical inquiry.
See additional summaries on Descartes' "Discourse on the Method":
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