Introduction to Astronomy

approaches. The place in the order of learning [is intended to prepare] the mind of the student: so that once read, it establishes what ought to be read next, directing them toward the understanding of the disciplines with sound judgment. The classification of the types of knowledge and the number of all its parts makes the journey attentive and the student teachable. Since, therefore, among all the writers of this art, none has been found until now who could either respond to those who contradict it or provide an argument for those who approve of it—and furthermore, no one who has written on the art in its entirety—our intention in this work is both to resist the former and to provide a foundation for the latter, and to hand down the complete art with divine assistance. From this, it is clear that a great benefit follows: that those who hereafter devote their labor to this craft will not give up or fail because they lack the necessary aids usually scattered across various works. Since we have deemed it necessary to confirm the work with the specific names of the author and the book, we state this title as a heading: The Introduction to Astrology by Albumasar of Balkh Albumasar (787–886 AD) was a leading Persian Muslim astrologer whose works were central to the revival of astrology in medieval Europe.. For this reason, after studying astronomy, this must be read in the first place regarding the theoretical—that is, the principal and general part of this art—published and described in eight divisions, each subdivided into its own distinctions. ¶ The five chapters of the first division: First, on the discovery of astrology. Second, on the effect of the motion of the stars. Third, on the quality of the effect. Fourth, on the confirmation of astrology. Fifth, on the utility of astrology.

Chapter One.

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First, therefore: what cause and what reason first incited man, placed upon the earth, to scrutinize the decrees of celestial philosophy, shall then be seen as it is explained. For it does not seem that such a great journey was undertaken by an unforeseen movement or the sudden impulse of just anyone, nor traversed without the highest zeal and expense. ¶ We divide, therefore, all knowledge of the heavenly bodies and stars into a twin species: the motion of the celestials and the effects of those motions. The first species is called universal mathematical wisdom original: "mathematica vniuersalis sapientia"; here referring to what we now call astronomy.. Indeed, it hands down the complete and perfect knowledge of the quantity and habit of the circles and celestial motions in themselves—firstly, and then in relation to others down to the globe of the earth. Since the body of the earth is a round globe, the highest circle The Primum Mobile or the outermost sphere of the heavens., by divine power perpetually surrounding the others contained within their spheres, turns them from the east through the west in a complete circuit day and night. Whence the Sun Symbol for the Sun must necessarily rise and set at different times for different nations in various parts of the lands; for some it is turned one way, and thus for some it is day while for others it is night. For among the circles between the highest sphere and the earth, some move with the highest, others move contrary to it. Indeed, almost every kind of stellar motion is contrary [to the daily rotation]. The part concerning the quantity and quality of the higher motions is open to human senses. Whence all science takes its beginning from the evidence of reasons, from positions, calculation, proportion, and measure; the subject matter necessarily brings the proof, so that it follows that those who do not proceed by this wisdom are both weak in sense and estranged from reason. ¶ This universal wisdom, therefore, Ptolemy Claudius Ptolemy, the 2nd-century Greco-Egyptian polymath. handed down after a certain Hamus in his book, the Almagest; and afterwards I, Albumasar, in such works of our predecessors, have followed the discourse of the celestials in the Zij al-Kabir original: "richene elchebir"; referring to his "Great Astronomical Tables."; and we have done so as well. The second species is natural [astrology], no less universal in its own kind, concerning the natures and properties of the stars and bodies...