1. Galileo, 1564–1641, and the group of scientists.
2. Bacon, 1561–1626.
3. Hobbes, 1588–1679.
4. The Rationalists.
Descartes, 1596–1650.
Spinoza, 1632–1677.
Leibnitz, 1646–1716.
Countries other than Italy and Germany come upon the philosophic stage during the eighty-nine years of the period of teeming natural science. England is represented by Bacon and Hobbes, France by Descartes, Holland by the Jew, Spinoza, and, at the end of the period, Germany by Leibnitz. Still Italy yields the most influential thinker of them all,—Galileo, who is the most prominent of a long series of astronomers coming from many countries. The most completely representative is Descartes, who was the founder of the Rationalistic school; for he was not only interested in mathematics itself, but in the application of mathematics to metaphysical questions. Neither as influential as Galileo, nor as comprehensive as Descartes, the Englishmen, Bacon and Hobbes, were nevertheless important as the forerunners of the English empirical school. Spinoza is more of a “world’s philosopher” than any of the others, and he joins in his doctrine the scholasticismof the Middle Ages and the mathematics of the Renaissance; while Leibnitz occupies the position between the Enlightenment and the Renaissance.
The Mathematical Astronomers. After enthusiastically canvassing the traditional theories of antiquity, the Humanists had been unable to find one which would explain and organize the newly accumulated materials of their “new world.” But working in more or less narrow circles, natural science had already made a beginning in the midst of the Humanists. Beginning with Copernicus, an interest in physics and astronomy had been aroused, but in these early days it was more speculative than empirical. The speculations of the astronomers had but little influence upon their own time. However, when the ancient theories proved inadequate to explain the facts of the “new world,” and especially when the empirical researches of Galileo confirmed the speculations of his predecessors, the Renaissance turned away from antiquity to nature herself for an explanation. This was about the year 1600, the year of the beginning of the Natural Science period.
The most prominent of these astronomers were—