Selections from the Catholic Encyclopedia on Astrology:

“Up to the time of the Crusades, Christian countries in general were spared any trouble from a degenerate astrology. Only natural astrology, the correctness of which the peasant thought he had recognized by experience secured a firm footing in spite of the prohibition of Church and State. But the gradually increasing influence of Arabic learning upon the civilization of the West, which reached its highest point at the time of the Crusades was unavoidably followed by the spread of the false theories of astrology. This was a natural result of the amalgamation of the teachings of pure astronomy with astrology at the Mohammedan seats of learning. The spread of astrology was also furthered by the Jewish scholars living in Christian lands, for they considered astrology as a necessary part of their cabalistic and Talmudic studies.”
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“The public importance of astrology grew as the internal disorders of the Church increased and the papal and imperial power declined. Towards the close of the Middle Ages nearly every petty prince, as well as every ruler of importance, had his court astrologer upon whose ambiguous utterances the weal and the woe of the whole country often depended.”
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“The revival of classical learning brought with it a second period of prosperity for astrology. Among the civilized peoples of the Renaissance period, so profoundly stirred by the all-prevailing religious, social and political ferment, the astrological teaching which had come to light with other treasures of ancient Hellenic learning found many ardent disciples. The romantic trend of the age and its highly cultivated sensuality were conditions which contributed to place this art in a position far higher than any it had attained in its former period of prosperity. The forerunners of Humanism busied themselves with astrology, and but few of them perceived the dangerous psychical effect of its teachings upon the masses.”
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“Emperors and popes became votaries of astrology– the Emperors Charles IV and V, and Popes Sixtus IV, Julius II, Leo X, and Paul III. When these rulers lived astrology was, so to say, the regulator of official life; it is a fact characteristic of the age, that at the papal and imperial courts ambassadors were not received in audience until the court astrologer had been consulted.”
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“The influence of the Copernican theory, the war of enlightened minds against pseudo-prophetic wisdom and the increasing perception of the moral and psychical damage wrought by astrological humbug at last brought about a decline in the fortunes of astrology, and that precisely in Wallenstein’s time. At the same period astrological tracts were stil being written by the most celebrated of English astrologers, William Lilly of Diseworth, Leicestershire, who received a pension of 100 pounds from Cromwell’s council of state, and who, in spite of some awkward incidents, had no little political influence with Charles II. Among his works was a frequently republished “Christian Astrology”. Shakespeare (in King Lear) and Milton were acquainted with and advocated astrological theories, and Robert Fludd was a representative of the art at the royal court. Francis Bacon, it is true, sought to win adherents for a purified and reformed astrology in order to destroy the existing form of the art. It was Jonathan Swift who in his clever satire, “Prediction for the Year 1708 by Isaac Bickerstaff, Esq”, which deserves to be read even at the present day, gave the deathblow to the belief of English society in astrology. The last astrologer of importance on the Continent was Jean-Baptiste Marin, who issued “Astrologia Gallica” (1661). The greatly misunderstood Swiss naturalist Theophrastus Paracelsus was an opponent of astrology, and not its advocate, as was formerly inferred from writings erroneously attributed to him. The rapid growth of experimental investigation in the natural sciences in those countries which had been almost ruined, socially and politically; by the Thirty Years War completely banished the astrological parasites from society. Once more astrology fell to the level of a vulgar superstition, cutting a sorry figure among the classes that still had faith in the occult arts. The peasant held fast to his belief in natural astrologist and to this belief the progress of the art of printing and the spread of popular education contributed largely. For not only were there disseminated among the rural poor “farmer’s almanacs”, which contained information substantiated by the peasant’s own experience, but the printing-presses also supplied the peasant with a great mass of cheap and easily understood books containing much fantastic astrological nonsense.”
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“The remarkable physical discoveries of recent decades, in combination with the growing desire for an elevated philosophico-religious conception of the world and the intensified sensitiveness of the modern cultured man — all these together have caused astrology to emerge from its hiding place among paltry superstitions. The growth of occultistic ideas, which should, perhaps, not be entirely rejected, is reintroducing astrology into society. This is especially true of judicial astrology, which, however, by its constant encouragement of fatalistic views unsettles the belief in a Divine Providence. At present Judicial astrology is not justified by any scientific facts.”
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“Co-incident with the spread of old astrology in old Israel and the decline of the nation was the diffusion of demonology. The Jewish prayers to the planets, in the form in which they are preserved with others in Codex Paris, 2419 (folio 277r), came into existence at the time when Hellenism first flourished in the East, namely, the third and second centuries B.C. In these prayers special angels and demons are assigned to the different planets; the greatest and most powerful planet Saturn having only one angel, Ktetoel, and one demon, Beelzebub. These planetary demons regulated the destiny of men.”
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“The lower the Jewish nation sank in the scale of religion and civilization the greater was the power gained by the erratic doctrines of astrology and the accompanying belief in demonology. The earthly labours of the Saviour purified this noxious atmosphere. The New Testament is the opponent of astrology, which, by encouraging an apathetic fatalism, prevents the development of and elevating and strengthening trust in a Divine Providence.”
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Jacobi, M. (1907). Astrology. In The Catholic Encyclopedia. New York: Robert Appleton Company. Retrieved April 17, 2012 from New Advent: http://www.newadvent.org/cathen/02018e.htm

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