Modern education started with these men. Before this period there had been a sterile age in which the fundamental purpose of education was only to teach men how to protect the soul and to serve God. This humanistic principle, however, failed to advance knowledge of the laws of nature, and the researches of the scientists gradually caused a strong reaction against it. This in turn resulted in further advances being made, not only in the sciences, but in all departments of learning. The way was paved for the era of naturalism, developed by Hobbes, Locke, Descartes, Voltaire, Kant, Rousseau, and others. Naturalism aimed at explaining all phenomena in the simplest terms, and correlating all things by universal principles. It has received a great impetus in modern times from the Darwinian theory of evolution. The great scientific discoveries of the sixteenth and seventeenth centuries had other important educational effects. They led to professional specialization and the founding of scientific institutions, schools, and universities. The Lyncean Society of Scientists was founded in Italy in Galileo's time. It subsequently became, in 1657, the Accademia del Cimento. The Royal Society of England was organized about 1645 and chartered in 1662. It did much valuable scientific work from its inception. It has assisted the foremost scientists in their work, directed scientific researches, and financed the printing of scientific records and the carrying out of foreign expeditions. Nearly all the leading countries in the world have formed institutions with similar aims. The chemical discoveries of Boyle attracted widespread attention and led to investigations started with the view of discovering the constitution of matter. Hermann Boerhaave (1668-1738) of Leyden, took up the study of organic chemistry. Stephen Hales (1677-1761) did similar work in England. Both of these chemists invented valuable laboratory processes and instruments. Hales improved the pneumatic trough used for collecting gases. Scientists were now furnished with the telescope, compass, sextant, microscope, barometer, thermometer, air pump, manometer, and other instruments so that cellular structures of plants, animals, and insects, the microbes and bacteria, the animalculæ found in water and in the sea, as well as the phenomena of the air, sky, and earth crust could now be studied by trained observers. The invention of these instruments caused workers to specialize more and more, and completely severed science from philosophy, of which it had been an appendage since the earliest times.