We must distinguish in the first place two kinds of astrology, viz., natural and judicial. The first proposed to foresee and announce the changes of the seasons, the rains, wind, heat, cold, abundance, or sterility of the ground, diseases, &c., by means of a knowledge of the causes which act on the air and on the atmosphere. The other is occupied with objects which would be still more interesting to men. It traced at the moment of his birth, or at any other period of his life, the line that each must travel according to his destiny. It pretended to determine our characters, our passions, fortune, misfortunes, and perils in reserve for each mortal.
We have not here to consider the natural astrology, which is a veritable science of observation and does not deserve the name of astrology. It is rather worthy to be called the meteorological calendar of its cultivators. More rural than their descendants of the nineteenth century, the ancients had recognised the connection between the celestial phenomena and the vicissitudes of the seasons; they observed these phenomena carefully to discover the return of the same inclemencies; and they were able (or thought they were) to state the date of the return of particular kinds of weather with the same positions of the stars. But the very connection with the stars soon led the way to a degeneracy. The autumnal constellations, for example, Orion and Hercules, were regarded as rainy, because the rains came at the time when these stars rose. The Egyptians who observed in the morning, called Sirius "the burning," because his appearance in the morning was followed by the great heat of the summer: and it was the same with the other stars. Soon they regarded them as the cause of the rain and the heat—although they were but remote witnesses. The star Sirius is still connected with heat—since we call it the dog-star—and the hottest days of the year, July 22nd to August 23rd, we call dog-days. At the commencement of our era, the morning rising of Sirius took place on the earlier of those days—though it does not now rise in the morning till the middle of August—and 4,000 years ago it rose about the 20th of June, and preceded the annual rise of the Nile.
The belief in the meteorological influence of the stars is one of the causes of judicial astrology. This latter has simply subjected man, like the atmosphere, to the influence of the stars; it has made dependent on them the risings of his passions, the good and ill fortune of his life, as well as the variations of the seasons. Indeed, it was very easy to explain. It is the stars, or heavenly bodies in general, that bring the winds, the rains, and the storms; their influences mixed with the action of the rays of the sun modify the cold or heat; the fertility of the fields, health or sickness, depend on these beneficial or injurious influences; not a blade of grass can grow without all the stars having contributed to its increase; man breathes the emanations which escaping from the heavenly bodies fill the air; man is therefore in his entire nature subjected to them; these stars must therefore influence his will and his passions; the good and evil passages in his career, in a word, must direct his life.
As soon as it was established that the rising of a certain star or planet, and its aspect with regard to other planets, announced a certain destiny to man, it was natural to believe that the rarer configurations signified extraordinary events, which concerned great empires, nations, and towns. And lastly, since errors grow faster than truth, it was natural to think that the configurations which were still more rare, such as the reunion of all the planets in conjunction with the same star, which can occur only after thousands of centuries, while nations have been renewed an infinity of times, and empires have been ruined, had reference to the earth itself, which had served as the theatre for all these events. Joined to these superstitious ideas was the tradition of a deluge, and the belief that the world must one day perish by fire, and so it was announced that the former event took place when all the planets were in conjunction in the sign of the Fishes, and the latter would occur when they all met in the sign of the Lion.
The origin of astrology, like that of the celestial sphere, was in all probability in upper Asia.
There, the starry heavens, always pure and splendid, invited observation and struck the imagination. We have already seen this with respect to the more matter-of-fact portions of astronomy. The Assyrians looked upon the stars as divinities endued with beneficent or maleficent power. The adoration of the heavenly bodies was the earliest form of religion among the pastoral population that came down from the mountains of Kurdestan to the plains of Babylon. The Chaldæans at last set apart a sacerdotal and learned caste devoted to the observation of the heavens; and the temples became regular observatories. Such doubtless was the tower of Babel—a monument consecrated to the seven planets, and of which the account has come down to us in the ancient book of Genesis.
A long series of observations put the Chaldæans in possession of a theological astronomy, resting on a more or less chimerical theory of the influence of the celestial bodies on the events of nations and private individuals. Diodorus Siculus, writing towards the commencement of our era, has put us in possession of the most circumstantial details that have reached us with regard to the Chaldæan priests.
At the head of the gods, the Assyrians placed the sun and moon, whose courses and daily positions they had noted in the constellation of the zodiac, in which the sun remained, one month in each. The twelve signs were governed by as many gods, who had the corresponding months under their influence. Each of these months were divided into three parts, which made altogether thirty-six subdivisions, over which as many stars presided, called gods of consultation. Half of these gods had under their control the things which happen above the earth, and the other half those below. The sun and moon and the five planets occupied the most elevated rank in the divine hierarchy and bore the name of gods of interpretation. Among these planets Saturn or old Bel, which was regarded as the highest star and the most distant from us, was surrounded by the greatest veneration; he was the interpreter par excellence—the revealer. Each of the other planets had his own particular name. Some of them, such as Bel (Jupiter), Merodaez (Mars), Nebo (Mercury), were regarded as male, and the others, as Sin (the Moon), and Mylitta or Baulthis (Venus), as females; and from their position relative to the zodiacal constellations, which were also called Lords or masters of the Gods, the Chaldæans derived the knowledge of the destiny of the men who were born under such and such a conjunction—predictions which the Greeks afterwards called horoscopes. The Chaldæans invented also relations between each of the planets and meteorological phenomena, an opinion partly founded on fortuitous coincidences which they had more or less frequently observed. In the time of Alexander their credit was considerable, and the king of Macedonia, either from superstition or policy, was in the habit of consulting them.
It is probable that the Babylonian priests, who referred every natural property to sidereal influences, imagined there were some mysterious relations between the planets and the metals whose colours were respectively somewhat analogous to theirs. Gold corresponded to the sun, silver to the moon, lead to Saturn, iron to Mars, tin to Jupiter, and mercury still retains the name of the planet with which it was associated. It is less than two centuries ago, since the metals have ceased to be designated by the signs of their respective planets. Alchemy, the mother of chemistry, was an intimately connected sister of Astrology, the mother of Astronomy.
Egyptian civilisation dates back to a no less remote period than that of Babylon. Not less careful observers than the Babylonish astrologers of the meteors and the atmospheric revolutions, they could predict certain phenomena, and they gave it out that they had themselves been the cause of them.