"Modern philosophy is usually considered to have begun with Descartes (1596-1650), who lived a generation after Galileo. The following is the usual image of Descartes and his philosophy: During the Middle Ages philosophy stood - if it stood independently at all - under the exclusive domination of theology and gradually degenerated into a mere analysis of concepts and elucidations of traditional opinion and propositions. It petrified into an academic knowledge which no longer concerned man and was unable to illuminate reality as a whole. Then Descartes appeared and liberated philosophy from this position. He began by doubting everything, but this doubt finally did run into something which could no longer be doubted, for, inasmuch as the skeptic doubts, he cannot doubt that he, the skeptic, is present and must be present in order to doubt at all. As I doubt I must admit that "I am." The "I," accordingly, is the indubitable. As a doubter, Descartes forced men into doubt in this way; he led them to think of themselves, as their "I." Thus the "I," human subjectivity, came to be declared the center of thought. From here originated the I-viewpoint of modern times and its subjectivism. p. 98-99"