Descartes claims to have found a particularly effective method of guiding his reason that has helped him to make many significant discoveries in his scientific research. He undertakes to explain his method by means of autobiography: he tells the story of his intellectual development and of how he came upon this method. He developed his method largely in reaction to the schooling in Aristotelian philosophy that he received at the hands of the Jesuits. He had been told that he would find knowledge and certainty in his schooling, but came out thoroughly dissatisfied. He had found no certainty, only ever-increasing doubts, so he left school, and traveled the world, learning about different people and different customs.