Strategies of Defending Astrology: A Continuing Tradition by Teri Gee A thesis submitted in conformity with the requirements for the degree of Doctorate of Philosophy Institute for the History and Philosophy of Science and Technology University of Toronto © Copyright by Teri Gee (2012) Strategies of Defending Astrology: A Continuing Tradition Teri Gee Doctorate of Philosophy Institute for the History and Philosophy of Science and Technology University of Toronto 2012 Abstract Astrology is a science which has had an uncertain status throughout its history, from its beginnings in Greco-Roman Antiquity to the medieval Islamic world and Christian Europe which led to frequent debates about its validity and what kind of a place it should have, if any, in various cultures. Written in the second century A.D., Ptolemy’s Tetrabiblos is not the earliest surviving text on astrology. However, the complex defense given in the Tetrabiblos will be treated as an important starting point because it changed the way astrology would be justified in Christian and Muslim works and the influence Ptolemy’s presentation had on later works represents a continuation of the method introduced in the Tetrabiblos. Abû Ma‘shar’s Kitâb al- Madkhal al-kabîr ilâ ‘ilm ahk. âm al-nujûm, written in the ninth century, was the most thorough surviving defense from the Islamic world. Roger Bacon’s Opus maius, although not focused solely on advocating astrology, nevertheless, does contain a significant defense which has definite links to the works of both Abû Ma‘shar and Ptolemy. As such, he demonstrates another stage in the development of astrology. These three works together reveal the threads of a trend of a rationalized astrology separated from its mythical origins which began with Ptolemy and survived through both medieval Islam and medieval Europe. In the two examples of defending ii astrology I have used, Abû Ma‘shar and Roger Bacon, Ptolemy’s influence can be seen to have persisted from the second century through to the thirteenth, and the nature of the differences in their defenses illustrates the continuation and evolution of the tradition of defending astrology. iii Acknowledgments A large number of people deserve my thanks for their help, support and encouragement during the seven years I have been working on my dissertation. First and foremost, I would like to thank my advisor, Prof. Alexander Jones, for his limitless patience and for the guidance he gave me, even after leaving the University of Toronto. He worked with me over long distances and, when possible, made himself available to answer the many questions I had. In addition, I would also like to thank Prof. Craig Fraser, for his constant support and willingness to help me complete my dissertation from a distance, and Prof. Bert Hall, for stepping in at the last minute and his breadth of knowledge which made my dissertation better. In addition, Prof. Jamil Ragep, as my external, gave me a lot of excellent feedback and ideas of how to make this dissertation into a publishable work. I am indebted to him for the time he took. Prof. Janis Langins was also helpful in acting as my internal external reader. Special thanks must go to Professor Abdel- Khalig Ali, my Arabic professor, who gave me extensive help on my Abû Ma‘shar translation, going far beyond the call of duty in his position as my teacher. I am also grateful for the teaching opportunities provided by the Institute for the History and Philosophy of Science and Technology and The Chang School at Ryerson University. I want to thank Denise Horsley and Muna Salloum in the office of the Institute for being able to answer all my questions and for helping me organize my education and finances. I must also give thanks to the other members of the Gerstein Gang, those of us working on our dissertations and sharing lunchtime breaks. During those inevitable problems and discouragements which arise during the research process, we were able to get a lot of support from each other. Last but not least, I am grateful for the support of my family who has been there for me through nearly eight years of graduate school, especially my parents, Jerald and Toni Gee. iv Table of Contents Preface 1 The Origin of Astrology and its Place in the Sciences 1.1 Definition of Terminology 1.2 Perceptions of Astrology’s Origins 1.3 The Reality: Egyptian Astrology 1.4 The Reality: Mesopotamian Origins 1.5 Babylonian Horoscopes 1.6 Astronomical and Cosmological Foundations of Greek Astrology 1.7 Greek Divination 1.8 The Rise of Greco-Roman Astrology 1.9 Determinism 1.10 Defending the Sciences 1.11 Polemics Against Astrology 1.12 Defenses of Astrology 2 Ptolemy’s Defense of Astrology 2.1 Ptolemy’s Life and Works 2.2 Ptolemy’s Philosophy 2.3 Tetrabiblos 2.4 Ptolemy’s Defense of Astrology 2.5 The Definition of Astrology 2.6 Why Practice Astrology? 2.7 The Benefits of Astrology 2.8 Determinism in the Tetrabiblos 2.9 Conclusion 3 Transmission to the Islamic World 3.1 Transmission of Ptolemy’s Tetrabiblos 3.2 Astrology in Early Islam 3.3 Conclusion 4 Abû Ma‘shar’s Defense of Astrology 4.1 Life and Works 4.2 Kitâb al-Madkhal al-kabîr ilâ ‘ilm ahk. âm al-nujûm 4.3 Reception and Transmission 4.4 Abû Ma‘shar’s Defense of Astrology 4.5 Astronomy vs. Astrology - Abû Ma‘shar’s definition 4.6 Al-qiyâs - Abû Ma‘shar’s use of comparisons and analogies 4.7 The Benefits of Astrology 4.8 Determinism in Abû Ma‘shar’s Astrology 4.9 Conclusion of Abû Ma‘shar’s Defense of Astrology v 5 The Latin Tradition of Astrology 5.1 Astrology in the Roman Empire 5.2 The Christianized Empire 5.3 Learning in the Middle Ages: The Encyclopedic Tradition 5.4 Arabic-Latin Translation Movement 5.5 Europe in the High Middle Ages 5.6 Astrology in the High Middle Ages 6 Roger Bacon’s Defense of Astrology 6.1 Life 6.2 Thought and Works 6.3 Opus maius 6.4 Astrology in the Opus maius 6.5 Definition and Differentiation 6.6 How Bacon’s Astrology Works 6.7 The Benefits of Astrology 6.8 Determinism in Bacon’s Astrology 7 Conclusion 7.1 Ptolemy as a Source for Astrology 7.2 Ptolemy and Abû Ma‘shar: Originality of the Arguments in Kitâb al-Madkhal al- kabîr 7.3 Bacon and his Predecessors: The Originality of Bacon’s Defense of Astrology 7.4 The Continuing Tradition of Defending Astrology Bibliography Appendix: Arabic text of Kitâb al-Madkhal al-kabîr ilâ ‘ilm ahk. âm al-nujûm vi 1 Preface The science of astrology has been attested in surviving literature beginning in the Hellenistic period in works such as Geminus’ Isagoge and Cicero’s De divinatione and De fato. The practice of casting individual horoscopes dates back further, to fifth-century Babylon, while celestial divination in general has been attested at least as early as the second millennium B.C. with the celestial omens found in the Enuma Anu Enlil. From these early beginnings, astrology has had a consistent presence in the surviving Greco-Roman, Arabic and Latin literature. Handbooks on astrology, as well as philosophical descriptions of the science, have been translated from Greek into Latin, from Greek into Arabic and from Arabic into Latin. Besides the texts written about astrology, attacks on the science are also present in the literature from Antiquity into the Renaissance. Astrology was popular enough that the astrological texts were often the first translated. It was considered dangerous enough to get the attention of many Christian and Muslim scholars, and astrology has been considered the practical application of astronomy at least from the time of Ptolemy. Clearly, astrology forms an important part of the history of science. Nevertheless, work on the history of astrology has been slow in progressing, in part, because of a perception well-illustrated by George Sarton when he famously described the information within The Book of the Zodiac, a translation of Mandaean texts, as “a wretched collection of omens, debased astrology, and miscellaneous nonsense, ultimately derived from Arabic, Greek, Persian, and all of the superstitious flotsam that was preserved in the Near East.”1 This idea of the history of astrology as being the study of a “wretched subject” has been 1Sarton. 1950, p. 374. For another example of Sarton’s dislike of astrology, see his 1954 review of Cramer’s Astrology in Roman Law and Politics in Speculum 31: 156-161. 2 summarily dismissed by many historians, beginning with Neugebauer’s equally famous reply “The Study of Wretched Subjects” which pointed out the value of studying this so-called pseudoscience. Even in valuable articles such as Anthony Long’s 1982 article “Astrology: Arguments pro and contra,” we see numerous comments denigrating the practice of astrology, such as his description of Ptolemy’s work in the Tetrabiblos as “misplaced ingenuity.”2 In contrast, David Pingree, in his 1992 article “Hellenophilia versus the History of Science,” states that historians cannot be confined to a modern view of what is science and what is worth studying. It does not matter whether one believes astrology to be true or not. What matters is that those in the past did see it as a science and treated it as such.3 The Mesopotamian foundations of Greek astrology and the practice of celestial divination have seen a number of works published in the last century. In contrast to the pace of research in Greco-Roman and later astrology, studies of the omen literature have acquired a prominent place in Assyriology.