The entire existence of states and individuals, down to the slightest incidents, was thought to depend on the stars. The absolute control they were supposed to exercise over everybody's daily condition, even modified the language in every-day use and left traces in almost all idioms derived from the Latin. If we speak of a martial, or a jovial character, or a lunatic, we are unconsciously admitting the existence, in these heavenly bodies (Mars, Jupiter, Luna) of their ancient qualities. It must be acknowledged, however, that the Grecian spirit tried to combat the folly that was taking hold of the world, and from the time of its propagation astrology found opponents among the philosophers. The most subtle of these adversaries was the probabilist Carneades, in the second century before our era. The topical arguments which he advanced, were taken up, reproduced, and developed in a thousand ways by later polemicists. For instance, Were all the men that perish together in a battle, born at the same moment, because they had the same fate? Or, on the other hand, do we not observe that twins, born at the same time, have the most unlike characters and the most different fortunes? But dialectics are an accomplishment in which the Greeks ever excelled, and the defenders of astrology found a reply to every objection. They endeavored especially to establish firmly the truths of observation, upon which rested the entire learned structure of their art: the influence of the stars over the phenomena of nature and the characters of individuals. Can it be {167} denied, they said, that the sun causes vegetation to appear and to perish, and that it puts animals _en rut_ or plunges them into lethargic sleep? Does not the movement of the tide depend on the course of the moon? Is not the rising of certain constellations accompanied every year by storms? And are not the physical and moral qualities of the different races manifestly determined by the climate in which they live? The action of the sky on the earth is undeniable, and, the sidereal influences once admitted, all previsions based on them are legitimate. As soon as the first principle is admitted, all corollaries are logically derived from it.