Trying to write a comprehensive history of science up to the scientific revolution in a single volume is the historian of science’s equivalent to squaring the circle. It can’t actually be done, it must fall short in various areas, but doesn’t prevent them from trying. The latest to attempt squaring the history of science circle is Ofer Gal in his The Origins of Modern Science: From Antiquity to the Scientific Revolution.
Gal’s book has approximately 380 pages and given what I regard as the impossibility of his task, I decided, if possible, to cut him some slack in this review. To illustrate the problem, David Lindberg’s The Beginnings of Western Science, with which Gal is definitely competing, has approximately 370 pages and only goes up to 1450 and has been criticised for its omissions. The Cambridge History of Science requires three volumes with an approximate total of 2250 pages to cover the same period as Gal and its essays can best be regarded as introductions to further reading.
CUP are marketing Gal’s book as a textbook for schools and university students, which means, in my opinion, a higher commitment to historical factual accuracy, so where I might be prepared to cut some slack on possible omissions, I’m not prepared to forgive factual errors. If you are teaching beginners, which this book aims to do, then you have an obligation to get your facts right. The intended textbook nature is reflected in the academic apparatus. There is no central bibliography of sources, instead at the end of each section there is a brief list of primary and secondary sources for that section. This is preceded by a list of essay type questions on the section; questions that are more of a philosophical than historical nature. The book has neither foot nor endnotes but gives occasional sources for quotes within the main text in backets.
Gal’s book opens with a thirty-page section titled, Cathedrals, which left me wondering what to expect, when I began reading. Actually, I think it is possibly the best chapter in the whole book. What he does is to use the story of the origins and construction of the European medieval cathedrals to illustrate an important distinction, in epistemology, between knowing-how and knowing-that. It is also the first indication that in the world of the traditional history and philosophy of science Gal is more of a philosopher than a historian, an impression that is confirmed as the book progresses. At times throughout the book, I found myself missing something, actual science.
Chapter two takes the reader into the world of ancient Greek philosophy and give comparatively short and concise rundowns on the main schools of thought, which I have to admit I found rather opaque at times. However, it is clear that Gal thinks that the origins of science are to be found in ancient Greece, as he completely ignores the scientific activities in other earlier culture, and that Aristotle is very much the main man. This sets the tone for the rest of the book, which follows a very conventional script that is, once again in my opinion, limited and dated.
The following section is the Birth of Astronomy, which Gal attributes entirely to the Greeks, no Egyptians, no Babylonians. He starts with Thomas Kuhn’s two sphere model that is the sphere of the Earth sitting at the centre of the sphere of the heavens and here we get a major factual error. He writes:
For the astronomers of ancient Mesopotamia and the Aegean region, that model was of two spheres: the image of our Earth, a sphere, nestled inside the bigger sphere of the heavens.
Unfortunately, for Gal, the astronomers of ancient Mesopotamia were flat earthers. Later in the section, Gal informs us that Babylonian astronomy was not science. I know an awful lot of historians of astronomy, who would be rather upset by this claim. Rather bizarrely in a section on ancient astronomy, the use of simple observation instruments is illustrated with woodcuts from a book from 1669 showing a cross-staff, first described in the 14th century by Levi den Gerson, and a backstaff, which was invented by John Davis in 1594. In the caption the backstaff is also falsely labelled a sextant. He could have included illustration of the armillary sphere and the dioptra, instruments that Hipparchus and Ptolemy actually used, instead.
Apart from these errors the section is a fairly standard rundown of Greek astronomical models and theories. As, apparently, the Greeks were the only people in antiquity who did science and the only science worth mentioning here is astronomy, we move on to the Middle Ages.
We get presented with a very scant description of the decline of science in late antiquity and then move on to the The Encyclopedic Tradition. Starting with the Romans, Cicero gets a positive nod and Pliny a much more substantial one. Under the medieval encyclopedist, we get Martianus Capella, who gets a couple of pages, whereas Isidore and Bede only manage a couple of lines each. We then get a more substantial take on the medieval Christian Church, although Seb Falk would be disappointed to note the lack of science here, the verge-and-foliot escapement and computus both get a very brief nod. Up next is the medieval university, which gets a comparatively long section, which however contains, in this context, a very strange attack on the university in the twenty first century. Gal also opinions:
They [medieval students] would study in two ways we still use and one which we have regrettably lost.
The three ways he describes are the lectura, the repititio, and the desputatio, so I must assume that Gal wishes to reintroduce the desputatio into the modern university! Following this are two whole pages on The Great Translation Project. This is somewhat naturally followed by Muslim Science. The section on the medieval university is slightly longer than that devoted here to the whole of Muslim science, with a strong emphasis on astronomy. In essence Gal has not written a book on the origins of modern science but one on the origins of modern astronomy with a couple of side notes nodding to other branches of the sciences. He devotes only a short paragraph to al-Haytham’s optics and the medieval scholars, who adopted it. Put another way, the same old same old.
The next section of the book bears the title The Seeds of Revolution and begins with a six-page philosophical, theological discourse featuring Ibn Rushd, Moshe ben Maimon and Thomas Aquinas. We now move on to the Renaissance. In this section the only nominal science that appears is Brunelleschi’s invention of linear perspective as an example of “the meeting of scholar and artisan.” A term in the title of the next subsection and throughout the section itself left me perplexed, The Movable Press and Its Cultural Impact. Can anybody help me? The history of printing is one of my areas of study and I have never ever come across the movable type printing press simply referred to as “the movable press.” I even spent half an hour searching the Internet and could not find the term anywhere. Does it exist or did Gal create it? The section itself is fairly standard. This is followed by a long section on Global Knowledge covering navigation and discovery, global commerce, practical mathematics driven by commerce, trade companies, and the Jesuits.
We then get a section, which is obviously a favourite area of Gal, given to space that he grants it, magic. Now I’m very much in favour of including what I would prefer to give the general title occult theories and practices rather than magic in a text on the history of science, so Gal wins a couple of plus points for this section. He starts with a philosophical presentation of the usual suspects, Neo-Platonism, Hermeticism, Kabbala et al. He then moves on to what he terms scientific magic, by which he means alchemy and astrology, which he admits are not really the same as magic, excusing himself by claiming that both are based on a form of magical thinking. He then attempts to explain each of them in less than three pages, producing a rather inadequate explanation in each case. In neither case does he address the impact that both alchemy and astrology actually had historically on the development of the sciences. Moving on we have Magic and the New Science. Here we get presented with cameos of the Bacons, both Roger and Francis, Pico della Mirandola, and Giambattista della Porta.
When dealing with Roger Bacon we get another example of Gal’s historical errors, he writes:
This enabled him to formulate great novelties, especially in optics. Theoretically, he turned Muslim optics into a theory of vision; practically, he is credited with the invention of the spectacles.
Here we have a classic double whammy. He didn’t turn Muslim optics into a theory of vision but rather took over and propagated the theory of vision of Ibn al-Haytham. I have no idea, who credits Roger Bacon with the invention of the spectacles, in all my extensive readings on the history of optics I have never come across such a claim, maybe just maybe, because it isn’t true.
Roughly two thirds of the way through we are now approaching modern science with a section titled, The Moving Earth. I’ll start right off by saying that it is somewhat symbolic of what I see as Gal’s dated approach that the book that he recommends for Copernicus’ ‘revolution’ is Thomas Kuhn’s The Copernican Revolution, a book that was factually false when it was first publish and hasn’t improved in the sixty years since. But I’m ahead of myself.
The section starts with a very brief sketch of Luther and the reformation, which function as a lead into a section titled, Counter-Reformation and the Calendar Reform. Here he briefly mentions the Jesuits, whom he dealt with earlier under Global Knowledge. He writes:
The Jesuits, as we’ve pointed out, turned from the strict logicism of traditional Church education to disciplines aimed at moving and persuading: rhetoric, theater, and dance. Even mathematics was taught (at least to missionaries-to-be) for its persuasive power.
Ignoring this rather strange presentation of the Jesuit strictly logical Thomist education programme, I will just address the last sentence. Clavius set up the most modern mathematical educational curriculum in Europe and probably the world, which was taught in all Jesuit schools and colleges throughout the world, describing it as “even mathematics was taught” really is historically highly inaccurate. Gal now delivers up something that I can only describe as historical bullshit, he writes: (I apologies for the scans but I couldn’t be arsed to type all of it.)
I could write a whole blog post trying to sort out this rubbish. The bit about pomp and circumstance is complete rubbish, as is, in this context, the section about knowing the exact time that had passed, since the birth of Christ. The only concern here is trying to determine the correct date on which to celebrate the movable feasts associated with Easter. The error in the length of the Julian year, which was eleven minutes not a quarter of an hour, also has nothing to do with the procession of the equinoxes but simply a false value for the length of the solar year. The Julian calendar was also originally Egyptian not Hellenistic. The Church decided vey early on to determine the date of Easter astronomically not by observation in order not to be seen following the Jewish practice. The calendar reform was not part of/inspired by the Reformation/Counter-Reformation but it had been on the Church’s books for centuries. There had been several reforms launched that were never completed, usually because the Pope, who had ordered it, had died and his successor had other things on his agenda when he mounted the Papal Throne. Famously, Regiomontanus died when called to Rome by the Pope to take on the calendar reform. The calendar reform that was authorized by the Council of Trent, had been set in motion several decades before the Council. Ptolemy’s Almagest had reached Europe twice in translations, both from the Greek and from Arabic, in the twelfth century and not first in the fifteenth century. What was published in the fifteenth century and had a major impact, Copernicus learnt his astronomy from it, was Peuerbach’s and Regiomontanus’ Epitoma in Almagestum Ptolemae
Just to close although it has nothing to do with the calendar reform, the name Commentariolus for Copernicus’ short manuscript from about 1514 on a heliocentric system, was coined much later by Tyco Brahe.
I don’t know why I missed it the first time round, but Nicolaus Copernicus was not a “Polish friar.” We’ll ignore the Polish for today, as I’ve already explained this too many times in the past. A friar is a member of one of the mendicant orders founded in the twelfth or thirteenth century, and Copernicus was not a member of any mendicant order. Copernicus was a canon of the cathedral chapter of the Cathedral of Frombork, which is something else altogether. This may seem, to people who don’t know their way around clerical titles, like hair splitting, but it is on the level of calling the plumber, who comes to fix your burst water main, a carpenter. It is a prime example of Gal’s extremely slapdash approach to historical facts.
We now move on to Copernicus. His section on Copernicus and his astronomy is fairly good but we now meet another problem. For his Early Modern scientists, he includes brief biographical detail, which; as very much a biographical historian, I approve of, but they are unfortunately strewn with errors. He writes for example that Copernicus was “born in Northern Poland then under Prussian rule.” Copernicus was born in Toruń, at the time an autonomous, self-governing city under the protection of the Polish Crown. After briefly sketching Copernicus’ university studies he writes:
“Yet Copernicus had no interest in vita activa: throughout his life he made his living as a canon in Frombork (then Frauenburg), a medieval privilegium (a personally conferred status) with few obligations…”
The cathedral canons in Frombork were the government and civil service of the prince-bishopric of Warmia and Copernicus had very much a vita activa as physician to the bishop, as consultant on fiscal affairs, as diplomat, as governor of Allenstein, organizing its defences during a siege by the Teutonic Order, and much more. Copernicus’ life was anything but the quiet contemplative life of the scholar. Later he writes concerning Copernicus’ activities as astronomer, “his activities were supported by the patronage of his uncle, in whose Warmia house he set up his observatory.” Whilst Copernicus on completion of his studies initially lived in the bishop’s palace in Heilsberg from 1503 till 1510 as his uncle’s physician and secretary, following the death of his uncle he moved to Frombork, and it is here that he set up his putative observatory. Gal also writes, “It took him thirty years to turn his Commentariolus into a complete book – On the Revolutions – whose final proofs he reviewed on his death bed, never to see it actually in print.” The legend says the finished published book was laid in his hands on his death bed. He would hardly have been reviewing final proofs, as he was in a coma following a stroke.
This might all seem like nit picking on my part but if an author is going to include biographical details into, what is after all intended as a textbook, then they have an obligation to get the facts right, especially as they are well documented and readily accessible.
Rheticus gets a brief nod and then we get the standard slagging off of Osiander for his ad lectorum. Here once again we get a couple of trivial biographical errors, Gal refers to Osiander as a Lutheran and as a Protestant priest. Osiander was not a Lutheran, he and Luther were rivals. Protestants are not priests but pastors and Osiander was never a pastor but a Protestant preacher. Of course, Gal has to waste space on Bruno, which is interesting as he largely ignores several seventeenth century scientists, who made major contributions to the development of modern science, such as Christiaan Huygens.
We are now well established on the big names rally towards the grand climax. Up next is Tycho Brahe, who, as usual, is falsely credited with being the first to determine that comets, nova et all were supralunar changing objects, thus contradicting Aristotle’s perfect heavens cosmology. History dictates that Kepler must follow Tycho, with a presentation of his Mysterium Cosmographicum. Gal says that Kepler’s mother “keen on his education” “sent him through the Protestants’ version of a Church education – grammar school, seminary and the University of Tübingen.” No mention of the fact that this education was only possible because Kepler won a scholarship. Gal also tells us:
By 1611, Rudolf’s colorful court brought about his demise, as Rudolf was forced off his throne by his brother Mathias, meaning that Kepler had to leave Prague. The last two decades of his life were sad: his financial and intellectual standing deteriorating, he moved back to the German-speaking lands – first to Linz, then Ulm, then Regensburg, and when his applications to university posts declined, he took increasingly lower positions as a provincial mathematician. … He died in poverty in Regensburg in 1630…
First off, Rudolph’s Prague was German speaking. Although Mathias required Kepler to leave Prague, he retained his position as Imperial Mathematicus (which Gal falsely names Imperial Astronomer), although actually getting paid for this post by the imperial treasury had always been a problem. He became district mathematicus in Linz in 1612 to ensure a regular income, a post he retained until 1626. He moved from Linz to Ulm in 1626 in order to get his Rudolphine Tables printed and published, which he then took to the Book Fair in Frankfurt, to sell in order to recuperate the costs of printing. From 1628 he was court advisor, read astrologer, to Wallenstein in Sagan. He travelled to the Reichstag in Regensburg in 1630, where he fell ill and died. He had never held a university post in his life and hadn’t attempted to get one since 1600.
Having messed up Kepler’s biography, Gal now messes up his science. Under the title, The New Physical Optics, Gal gets Kepler’s contribution to the science of optics horribly wrong. He writes:
Traditional optics was the mathematical theory of vision. It studied visual rays: straight lines which could only change direction: refracted by changing media or reflected by polished surfaces. Whether these visual rays were physical entities or just mathematical representations of the process of vision, and what this process consisted of, was much debated. (…) But there was no debate that vision is a direct, cognitive relation between the object and the mind, through the eye. Light, in all of these theories, had an important, but secondary role:
Kepler abolished this assumption. Nothing of the object, he claimed, comes to and through the eye. The subject matter of his optics was no longer vision but light:
This transformation in the history of optics was not consummated by Kepler at the beginning of the seventeenth century but by al-Kindi and al-Haytham more than seven hundred years earlier. This was the theory of vision of al-Haytham mentioned above and adopted by Roger Bacon.
We then get a reasonable account of Kepler’s Astronomia nova, except that he claims that Kepler’s difficulties in finally determining that the orbit of Mars was an ellipse was because he was trapped in the concept that the orbits must be circular, which is rubbish. Else where Gal goes as far as to claim that Kepler guessed that the orbit was an ellipse. I suggest that he reads Astronomia nova or at least James Voelkel’s excellent analysis of it, The Composition of Kepler’s Astronomia Nova (Princeton University Press, 2001) to learn how much solid mathematical analysis was invested in that determination.
As always Galileo must follow Kepler. We get a very brief introduction to the Sidereus Nuncius and then an account of Galileo as a social climber that carries on the series of biographical errors. Gal writes:
Galileo’s father Vincenzo (c. 1520–1591) (…) A lute player of humble origins, he taught himself musical theory and acquired a name and enough fortune to marry into minor (and penniless) nobility with a book on musical theory, in which he relentless and venomously assaulted the canonical theory as detached from real musical practices.
This is fascinatingly wrong, because Gal gives as his source for Galileo’s biography John Heilbron’s Galileo, where we can read on page 2 the following:
Although Galileo was born in Pisa, the hometown of his recalcitrant mother, he prided himself on being a noble of Florence through his father, Vincenzo Galilei, a musician and musical theorist. Vincenzo’s nobility did not imply wealth but the right to hold civic office and he lived in the straitened circumstances usual in his profession. His marriage to Giulia, whose family dealt in cloth, was a union of art and trade.
The errors continue:
…he returned to the University of Pisa to study medicine, but stayed in the lower faculties and taught mathematics there from 1589. Two years later, he moved to Padua, his salary rising slightly from 160 Scudi to 160 Ducats a year. In 1599, he invented a military compass and dedicated it to the Venetian Senate to have his salary doubled and his contract extended for six years. When Paolo Sarpi (1552–1623), Galileo’s friend and minor patron, arranged for the spyglass to be presented and dedicated to the Senate in 1609, Galileo’s salary was doubled again and he was tenured for life.
Galileo actually broke off his medical studies and left the university, took private lessons in mathematics and was then on the recommendation of Cardinal del Monte, the Medici Cardinal, appointed to the professorship for mathematics in Pisa. He didn’t invent the military or proportional compass and didn’t dedicate it to the Senate and his salary wasn’t doubled for doing so. Although he did manufacture and sell a superior model together with paid lessons in its use. His salary wasn’t doubled for presenting a telescope to the Senate but was increased to 1000 Scudi.
Of course, we have a section titled, The Galileo Affair: The Church Divorces Science, the title revealing everything we need to know about Gal’s opinion on the topic. No, the Church did not divorce science, as even a brief survey of seventeenth century science following Galileo’s trial clearly shows. Gal states that, “The investigation of the Galileo affair was charged to Cardinal Roberto Bellarmine…”, which simply isn’t true. He naturally points out that Bellarmine, “condemned Bruno to the stake some fifteen years earlier.” Nothing like a good smear campaign.
At one point Gal discuses Bellarmine’s letter to Foscarini and having quoted “…if there were a true demonstration that the sun is at the center of the world and the earth in the third heaven, and that the sun does not circle the earth but the earth circles the sun, then one would have to proceed with great care in explaining the Scriptures that appear contrary; and say rather that we do not understand them than that what is demonstrated is false.
makes the following interesting statement:
Bellarmine was no wide-eyed champion of humanist values. He was a powerful emissary of a domineering institution, and he wasn’t defending only human reason, but also the Church’s privilege to represent it. He wasn’t only stressing that the Church would abide by “a true demonstration,” but also that it retained the right to decide what the criteria for such a demonstration were, and when they’ are met. [my emphasis]
The emphasised statement is at very best highly questionable and at worst completely false. Bellarmine was a highly intelligent, highly educated scholar, who had earlier in his career taught university courses in astronomy. He was well aware what constituted a sound scientific demonstration and would almost certainly have acknowledged and accepted one if one was delivered, without question.
On Galileo’s questioning by the Roman Inquisition Gal writes:
After the first interrogation, he [Galileo] reached a deal which didn’t satisfy the pope and was interrogated again.
This is simply factually wrong; no deal was reached after the first interrogation.
This review is getting far too long, and I think I have already delivered enough evidence to justify what is going to be my conclusion so I will shorten the next sections.
Gal suddenly seems to discover that there were scientific areas other than astronomy and there follows a comparatively long section on the history of medicine that starts with William Harvey then back tracks to ancient Greece before summarising the history of medicine down to the seventeenth century. This is in general OK, but I don’t understand why he devotes four and a half pages to the Leechbook a relatively obscure medieval English medical text, whereas midwives warrant less than two pages.
We are on the home stretch and have reached The New Science, where we discoverer that Galileo originated the mechanical philosophy. Really? No, not really. First up we get told that Buridan originated impetus theory. There is no mention of Johann Philoponus, who actually originated it or the various Arabic scholars, who developed it further and from whom Buridan appropriated it, merely supplying the name. We then get Galileo on mechanics, once again with very little prehistory although both Tartaglia and Benedetti get a mention. Guidobaldo del Monte actually gets acknowledged for his share in the discovery of the parabola law. However, Gal suggests that the guessed it! It’s here that he states that Kepler guessed that the orbit of Mars is an ellipse.
Up next the usual suspects, Descartes and Bacon and I just can’t, although he does, surprisingly, acknowledge that Bacon didn’t really understand how science works. Whoever says Bacon must say scientific societies, with a long discourse on the air pump, which seems to imply that only Boyle and Hooke actually did air pump experiments.
We now reach the books conclusion Sciences Cathedral, remember that opening chapter? This is, naturally, Newton’s Principia. Bizarrely, this section is almost entirely devoted to the exchange of letters between Hooke and Newton on the concept of gravity. Or it appears somewhat bizarre until you realise that Gal has written a whole book about it and is just recycling.
Here we meet our last botched biographical sketch. Having presented Hooke’s biography with the early demise of his father and his resulting financial struggles to obtain an education, Gal turns his attention to Isaac and enlightens his readers with the following:
Isaac Newton: While Hooke was establishing his credentials as an experimenter and instrument builder in Oxford, Isaac Newton (1642–1726) was gaining a name as a mathematical wiz in Cambridge. Like, Hooke, he was an orphan of a provincial clergy man from a little town in Lincolnshire on the east coast of England, and like him he had to work as a servant-student until his talents shone through.
Hannah Newton-Smith née Ayscough, Newton’s mother, would be very surprised to learn that Isaac was an orphan, as she died in 1679, when Isaac was already 37 years old. She would be equally surprised to learn that Isaac’s father, also named Isaac, who died before he was born, was a provincial clergyman. In reality, he was a yeoman farmer. Hannah’s second husband, Newton’s stepfather, Barnabus Smith was the provincial clergyman. Woolsthorpe where Newton was born and grew up was a very little town indeed, in fact it was merely a hamlet. Unlike Hooke who had to work his way through university, Newton’s family were wealthy, when he inherited the family estate, they generated an annual income of £600, a very large sum in the seventeenth century. Why his mother insisted on him entering Cambridge as a subsizar, that is as a servant to other students is an unsolved puzzle. Gal continues:
Newton was a recluse, yet he seemed to have had an intellectual charisma that Hooke lacked. He became such a prodigy student of the great mathematician Isaac Barrow (1630–1677) that in 1669 Barrow resigned in his favour from Cambridge’ newly established, prestigious Lucasian Professorship pf Mathematics.
Here Gal is recycling old myths. Newton was never a student of Isaac Barrow. Barrow did not resign the Lucasian chair in Newton’s favour. He resigned to become a theologian. However, he did recommend Newton as his successor. Further on Gal informs us that:
Newton waited until Hooke’s death in 1703 to publish his Opticks – the subject of the earlier debate – and became the Secretary of the Royal Society, which he brought back from the disarray into which it had fallen after the death of Oldenburg and most of its early members.
I’m sure that the Royal Society will be mortified to learn that Gal has demoted its most famous President to the rank of mere Secretary. This chapter also includes a discussion of the historical development of the concept of force, which to put it mildly is defective, but I can’t be bothered to go into yet more detail. I will just close my analysis of the contents with what I hope was just a mental lapse. Gal writes:
Newton presents careful tables of the periods of the planets of the planets as well as those of the moons of Jupiter and Mercury [my emphasis].
I assume he meant to write Saturn.
To close I will return to the very beginning of the book the front cover. As one can see it is adorned with something that appears at first glance to be an astrolabe. However, all the astrolabe experts amongst my friends went “what the fuck is that?” on first viewing this image. It turns out that it is a souvenir keyring sold by the British Museum. Given that the Whipple Museum of the History of Science in Cambridge has some very beautiful astrolabe, I’m certain that the CUP could have done better than this. The publishers compound this monstrosity with the descriptive text:
Cover image: habaril, via Getty Images. Brass astrolabe, a medieval astronomical navigation instrument.
We have already established that it is in fact not an astrolabe. The astrolabe goes back at least to late antiquity if not earlier, the earliest known attribution is to Theon of Alexandria (C. 335–405 CE), and they continued to be manufactured and used well into the nineteenth century, so not just medieval. Finally, as David King, the greatest living expert on the astrolabe, says repeatably, the astrolabe is NOT a navigation instrument.
Gal’s The Origins of Modern Science has the potential to be a reasonable book, but it is not one that I would recommend as an introduction to the history of science for students. Large parts of it reflect an approach and a standard of knowledge that was still valid thirty or forty years ago, but the discipline has moved on since then. Even if this were not the case the long list of substantive errors that I have documented, and there are probably others that I missed, display a shoddy level of workmanship that should not exist in any history book, let alone in an introductory text for students.
 Ofer Gal, The Origins of Modern Science: From Antiquity to the Scientific Revolution, CUP, Cambridge 2021.
 David C. Lindberg, The Beginnings of Western Science: The European Scientific Tradition in Philosophical, Religious, and Institutional Context, Prehistory to A.D. 1450, University of Chicago Press, Chicago and London, 2nd edition 2007.