The accounts that have been transmitted to us by the Chaldeans themselves of the antiquity of their learning, are blended with fable, and involved in considerable uncertainty. At the time when Callisthenes was requested by Aristotle to gain information concerning the origin of science in Chaldea, he was {43} informed that the ancestors of the Chaldeans had continued their astronomical observations through a period of 470,000 years; but upon examining the ground of this report, he found that the Chaldean observation reached no further backward than 1,903 years, or that, of course (adding this number to 331, B.C., the year in which Babylon was taken by Alexander), they had commenced in the year 2,234, B.C. Besides, Ptolemy mentions no Chaldean observations prior to the era of Nabonassar, which commenced 747 years B.C. Aristotle, however, on the credit of the most ancient records, speaks of the Chaldean Magi as prior to the Egyptian priests, who, it is well known, cultivated learning before the time of Moses. It appears probable that the philosophers of Chaldea were the priests of the Babylonian nation, who instructed the people in the principles of religion, interpreted its laws, and conducted its ceremonies. Their character was similar to that of the Persian Magi, and they are often confounded by the Greek historians. Like the priests in most other nations, they employed religion in subserviency to the ruling powers, and made use of imposture to serve the purposes of civil policy. Accordingly Diodorus Siculus relates (lib. ii., p. 31, compared with Daniel ii. 1, &c., Eccles. xliv. 3) that they pretended to predict future events by divination, to explain prodigies, interpret dreams, and avert evils or confer benefits by means of augury and incantations. For many ages they {44} retained a principal place among diviners. In the reign of Marcus Antoninus, when the emperor and his army, who were perishing with thirst, were suddenly relieved by a shower, the prodigy was ascribed to the power and skill of the Chaldean soothsayers. Thus accredited for their miraculous powers, they maintained their consequence in the courts of princes. (See Cic. de Divin. l. i., Strabo l. xv.--Sext. Emp. adv. Matt. l. v. Sec. 2, Aul. Gell. l. xiv. s. 1, Strabo l.c.) The mysteries of Chaldean philosophy were revealed only to a select few, and studiously concealed from the multitude; and thus a veil of sanctity was cast over their doctrine, so that it might more easily be employed in the support of civil and religious tyranny. The sum of the Chaldean cosmogony, as it is given in Syncellus (Chronic. p. 28), divested of allegory is, that in the beginning all things consisted of darkness and water; that BELUS, or a divine power, dividing this humid mass formed the world, and that the human mind is an emanation from the divine nature. (Perizon. in Orig. Bab. Voss. de Scient. Math. c. xxx. Sec. 5. Hottinger Hist. Or. p. 365. Herbelot Bib. Or. Voc. Zor. Anc. Un. Hist. vol. iii.