In the second place the East was the home of the learning of the world. The Greeks furnished the West not only philosophy and rhetoric but the sciences as well. Building on the mathematics and astronomy which they had learned from their Eastern neighbors and the Egyptians they soon developed these two sister sciences. Tradition says that in the sixth century B.C. the philosopher Thales predicted an eclipse of the sun; certainly a century later the Greeks had made great advances; and such were their attainments by the opening of our era that only in comparatively modern times has a new period in the history of astronomy and mathematics begun. In the descriptive sciences of botany and zoölogy especially the Greeks had reached a high position by the fourth century B.C. The work of Aristotle, of Theophrastus, and of others still holds the profound respect of all modern scientists who are familiar with the history of their subjects. In geography and mineralogy also their accomplishments were not inconsiderable; likewise in many branches of physics they did notable work; while Greek scientific medicine, already highly developed in Hippocrates’ day (c. 460-377 B.C.), was further advanced in the succeeding centuries. The works of Galen (129-c. 199 A.D.) remained the authoritative treatises for more than fourteen hundred years. All these sciences the Romans learned from the Greeks, and although in some fields they made notable application of their lessons, they never surpassed their teachers. Moreover Greece and Hellenized Asia Minor, Syria, and Egypt had a knowledge of the conduct of business, of banking, and of the details of administration which they gave to the western half of the Empire. Indeed Roman history between the battle of Actium and the reign of Diocletian from one point of view is the history of the spread of eastern ideas to the West and of their absorption there. Not only did captive Greece take her captor captive, but in a sense Egypt, Syria, and Asia Minor won their conquests as well. Many causes operated to further this intellectual domination of the Hellenized East over the Roman West. The eastern provinces had not suffered in the civil wars at the end of the Republic as had many parts of the West; their wealth was not wasted, and in general their social and economic relations were comparatively undisturbed. Under the wise administration of the Emperors these provinces grew richer; their inhabitants, especially the Greeks among them, gained a consciousness of their own intellectual superiority which they had not had in the last two centuries before our era. The influence of the East, therefore, was in many ways consciously exerted.