=2. The Growth of Science.= Since theory was regarded as completed, _attention was naturally turned upon the details of erudition and the specializing of science_. The natural sciences survived the systems of philosophy because of their usefulness. There was great interest in investigations in mathematics, natural science, grammar, philology, literary history and general history――and all with very rich results. It was the time of commentaries, criticism, collaboration of the work of the past and completion of the special work begun by the past. By far the greater number of the so-called “philosophers” of this time are connected with special science and literature, and not with metaphysics. It was in the Greek Islands and Egypt (Alexandria) that this advance was made. Nevertheless, it must be said that the advance in science was a good deal restricted. The empirical sciences are dependent on observation and experiment, and these opportunities were wanting at this time. Good progress was, however, made in mathematics and the sciences dependent on reasoning. Reasoning alone is incapable of advancing a science like physics, for physics depends on investigation. But even the prevalent skepticism of the time could not doubt the truths of mathematics. =3. Ethics became the Central Interest.= For the first time in the history of European thought ethics was no longer a part of politics. In the time of the autonomous Greek states ethics and politics were two sides of the same question both in theory and practice. Ethics and politics were not disjoined even by the Sophists, who nevertheless paved the way for the divorce of the two. Now for the first time ethical questions have become such that the individual must disregard the iron-bound political situation and answer them entirely with reference to himself. The decadent Greek state was no longer a moral entity in the eyes of the people, nor could the concentration of government in Rome raise the state to moral dignity. Moreover, life had become cosmopolitan. The nations were commingling. Ethics must meet the needs of men as human beings, and not as Athenians, Spartans, or Romans. Vices had become cosmopolitan and virtues must needs be cosmopolitan also. But cosmopolitanism is in the last analysis only individualism. The man who conceives his duty so large that it embraces the whole world is usually cold to any special interests except his own. The Roman dictators and afterwards the emperor were the personification of this cosmopolitan individualism which the subjects imitated so far as they could.