Category Archives: Book Reviews

Finding your way on the Seven Seas in the Early Modern Period

I spend a lot of my time trying to unravel and understand the complex bundle that is Renaissance or Early Modern mathematics and the people who practiced it. Regular readers of this blog should by now be well aware that the Renaissance mathematici, or mathematical practitioners as they are generally known in English, did not work on mathematics as we would understand it today but on practical mathematics that we might be inclined, somewhat mistakenly, to label applied mathematics. One group of disciplines that we often find treated together by one and the same practitioner consists of astronomy, cartography, navigation and the design and construction of tables and instruments to aid the study of these. This being the case I was delighted to receive a review copy of Margaret E. Schotte’s Sailing School: Navigating Science and Skill, 1550–1800[1], which deals with exactly this group of practical mathematical skills as applied to the real world of deep-sea sailing.

Sailing School001.jpg

Schotte’s book takes the reader on a journey both through time and around the major sea going nations of Europe, explaining, as she goes, how each of these nations dealt with the problem of educating, or maybe that should rather be training, seamen to become navigators for their navel and merchant fleets, as the Europeans began to span the world in their sailing ships both for exploration and trade.

Having set the course for the reader in a detailed introduction, Schotte sets sail from the Iberian peninsular in the sixteenth century. It was from there that the first Europeans set out on deep-sea voyages and it was here that it was first realised that navigators for such voyages could and probably should be trained. Next we travel up the coast of the Atlantic to Holland in the seventeenth century, where the Dutch set out to conquer the oceans and establish themselves as the world’s leading maritime nation with a wide range of training possibilities for deep-sea navigators, extending the foundations laid by the Spanish and Portuguese. Towards the end of the century we seek harbour in France to see how the French are training their navigators. Next port of call is England, a land that would famously go on, in their own estimation, to rule the seven seas. In the eighteenth century we cross the Channel back to Holland and the advances made over the last hundred years. The final chapter takes us to the end of the eighteenth century and the extraordinary story of the English seaman Lieutenant Riou, whose ship the HMS Guardian hit an iceberg in the Southern Atlantic. Lacking enough boats to evacuate all of his crew and passengers, Riou made temporary repairs to his vessel and motivating his men to continuously pump out the waters leaking into the rump of his ship, he then by a process of masterful navigation, on a level with his contemporaries Cook and Bligh, brought the badly damaged frigate to safety in South Africa.

Sailing School004

In each of our ports of call Schotte outlines and explains the training conceived by the authorities for training navigators and examines how it was or was not put into practice. Methods of determining latitude and longitude, sailing speeds and distances covered are described and explained. The differences in approach to this training developed in each of the sea going European nations are carefully presented and contrasted. Of special interest is the breach in understanding of what is necessary for a trainee navigator between the mathematical practitioners, who were appointed to teach those trainees, and the seamen, who were being trained, a large yawning gap between theory and practice. When discussing the Dutch approach to training Schotte clearly describes why experienced coastal navigators do not, without retraining, make good deep-sea navigators. The methodologies of these two areas of the art of navigation are substantially different.

The reader gets introduced to the methodologies used by deep-sea navigators, the mathematics developed, the tables considered necessary and the instruments and charts that were put to use. Of particular interest are the rules of thumb utilised to make course corrections before accurate methods of determining longitude were developed. There are also detailed discussions about how one or other aspect of the art of navigation was emphasised in the training in one country but considered less important in another. One conclusion the Schotte draws is that there is not really a discernable gradient of progress in the methods taught and the methods of teaching them over the two hundred and fifty years covered by the book.

Sailing School003.jpg

As well as everything you wanted to know about navigating sailing ships but were too afraid to ask, Schotte also delivers interesting knowledge of other areas. Theories of education come to the fore but an aspect that I found particularly fascinating were her comments on the book trade. Throughout the period covered, the teachers of navigation wrote and marketed books on the art of navigation. These books were fairly diverse and written for differing readers. Some were conceived as textbooks for the apprentice navigators whilst others were obviously written for interested, educated laymen, who would never navigate a ship. Later, as written exams began to play a greater role in the education of the aspirant navigators, authors and publishers began to market books of specimen exam questions as preparation for the exams. These books also went through an interesting evolution. Schotte deals with this topic in quite a lot of detail discussing the authors, publishers and booksellers, who were engaged in this market of navigational literature. This is detailed enough to be of interest to book historians, who might not really be interested in the history of navigation per se.

Schotte is excellent writer and the book is truly a pleasure to read. On a physical level the book is beautifully presented with lots of fascinating and highly informative illustrations. The apparatus starts with a very useful glossary of technical terms. There is a very extensive bibliography and an equally extensive and useful index. My only complaint concerns the notes, which are endnotes and not footnotes. These are in fact very extensive and highly informative containing lots of additional information not contained in the main text. I found myself continually leafing back and forth between main text and endnotes, making continuous reading almost impossible. In the end I developed a method of reading so many pages of main text followed by reading the endnotes for that section of the main text, mentally noting the number of particular endnotes that I wished to especially consult. Not ideal by any means.

This book is an essential read for anybody directly or indirectly interested in the history of navigation and also the history of practical mathematics. If however you are generally interested in good, well researched, well written history then you will almost certainly get a great deal of pleasure from reading this book.

[1] Margaret E. Schotte, Sailing School: Navigating Science and Skill, 1550–1800, Johns Hopkins University Press, Baltimore, 2019.

8 Comments

Filed under Book Reviews, History of Astronomy, History of Cartography, History of Mathematics, History of Navigation, Renaissance Science, Uncategorized

Calculus for the curious

Some weeks ago I got involved in a discussion on Twitter about, which books to recommend on the history of calculus. Somebody chimed in that Steven Strogatz’s new book would tell you all that you needed to know about the history of calculus. I replied that I couldn’t comment on this, as I hadn’t read it. To my surprise Professor Strogatz popped up and asked me if I would like to have a copy of his book. Never one to turn down a freebee, I naturally said yes. Very soon after a copy of Infinite Powers: The Story of Calculus The Language of the Universe arrived in the post and landed on my to read pile. Having now read it I can comment on it and intend to do so.

For those, who don’t know Steven Strogatz, he is professor of applied mathematics at Cornell University and the successful author of best selling popular books on mathematics.

Strogatz001

First off, Infinite Powers is not a history of calculus. It is a detailed introduction to what calculus is and how it works, with particular emphasis on its applications down the centuries, Strogatz is an applied mathematician, presented in a history-light frame story. Having said this, I’m definitely not knocking, what is an excellent book but I wouldn’t recommend it to anybody, who was really looking for a history of calculus, maybe, however, either as a prequel or as a follow up to reading a history of calculus.

The book is centred on what Strogatz calls The Infinity Principle, which lies at the heart of the whole of calculus:

To shed light on any continuous shape, object, motion, process, or phenomenon–no matter how wild and complicated it may appear–reimagine it as an infinite series of simpler parts, analyse those, and then add the results back together to make sense of the original whole.

Following the introduction of his infinity principle Strogatz gives a general discussion of its strengths and weakness before moving on in the first chapter proper to discuss infinity in all of its guises, familiar material and examples for anybody, who has read about the subject but a well done introduction for those who haven’t. Chapter 2 takes us  into the early days of calculus, although it didn’t yet have this name, and introduces us to The Man Who Harnessed Infinity, the legendary ancient Greek mathematician Archimedes and the method of exhaustion used to determine the value of π and the areas and volumes of various geometrical forms. Astute readers will have noticed that I wrote early days and not beginning and here is a good example of why I say that this is not a history of calculus. Although Archimedes put the method of exhaustion to good use he didn’t invent it, Eudoxus did. Strogatz does sort of mention this in passing but whereas Archimedes gets star billing, Eudoxus gets dismissed in half a sentence in brackets. The reader is left completely in the dark as to who, why, what Eudoxus is/was. OK here, but not OK in a real history of calculus. This criticism might seem petty but there are lots of similar examples throughout the book that I’m not going to list in this review and this is why the book is not a history of calculus and I don’t think Strogatz intended to write one; the book he has written is a different one and it is a very good one.

After Archimedes the book takes a big leap to the Early Modern Period and Galileo and Kepler with the justification that, “When Archimedes died, the mathematical study of nature nearly died along with him. […] In Renaissance Italy, a young mathematician named Galileo Galilei picked up where Archimedes had left off.” My inner historian of mathematics had an apoplectic fit on reading these statements. They ignore a vast amount of mathematics, in particular the work in the Middle Ages and the sixteenth century on which Galileo built the theories that Strogatz then presents here but I console myself with the thought that this is not a history of calculus let alone a history of mathematics. However, I’m being too negative, let us return to the book. The chapter deals with Galileo’s terrestrial laws of motion and Kepler’s astronomical laws of planetary motion. Following this brief introduction to the beginnings of modern science Strogatz moves into top gear with the beginnings of differential calculus. He guides the reader through the developments of seventeenth century mathematics, Fermat and Descartes and the birth of analytical geometry bringing together the recently introduced algebra and the, by then, traditional geometry. Moving on he deals with tangents, functions and derivatives. Strogatz is an excellent teacher he introduces a new concept carefully, explains it, and then shows how it can be applied to an everyday situation.

Having laid the foundations Strogatz move on naturally to the supposed founders of modern calculus, Leibnitz and Newton and their bringing together of the strands out of the past that make up calculus as we know it and how they fit together in the fundamental theorem of calculus. This is interwoven with the life stories of the two central figures. Again having introduced concepts and explained them Strogatz illustrates them with applications outside of pure mathematics.

Having established modern calculus the story moves on into the eighteenth century.  Here I have to point out that Strogatz perpetuates a couple of myths concerning Newton and the writing of his Principia. He writes that Newton took the concept of inertia from Galileo; he didn’t, he took it from Descartes, who in turn had it from Isaac Beeckman. A small point but as a historian I think an important one. Much more important he seems to be saying that Newton created the physics of Principia using calculus then translated it back into the language of Euclidian geometry, so as not to put off his readers. This is a widely believed myth but it is just that, a myth. To be fair it was a myth put into the world by Newton himself. All of the leading Newton experts have over the years very carefully scrutinised all of Newton’s writings and have found no evidence that Newton conceived and wrote Principia in any other form than the published one. Why he rejected the calculus, which he himself developed, as a working tool for his magnum opus is another complicated story that I won’t go into here but reject it he did[1].

After Principia, Strogatz finishes his book with a random selection of what might be termed calculus’ greatest hits, showing how it proved its power in solving a diverse series of problems. Interestingly he also addresses the future. There are those who think that calculus’ heyday is passed and that other, more modern mathematical tools will in future be used in the applied sciences to solve problems, Strogatz disagrees and sees a positive and active future for calculus as a central mathematical tool.

Despite all my negative comments, and I don’t think my readers would expect anything else from me, given my reputation, I genuinely think that this is on the whole an excellent book. Strogatz writes well and fluidly and despite the, sometimes, exacting content his book is a pleasure to read. He is also very obviously an excellent teacher, who is very good at clearly explaining oft, difficult concepts. I found it slightly disappointing that his story of calculus stops just when it begins to get philosophical and logically interesting i.e. when mathematicians began working on a safe foundation for the procedures that they had been using largely intuitively. See for example Euler, who made great strides in the development of calculus without any really defined concepts of convergence, divergence or limits, but who doesn’t appear here at all. However, Strogatz book is already 350-pages-long and if, using the same approach, he had continued the story down to and into the twentieth century it would probably have weighed in at a thousand plus pages!

Despite my historical criticisms, I would recommend Strogatz’s book, without reservations, to anybody and everybody, who wishes to achieve a clearer, deeper and better understanding of what calculus is, where it comes from, how it functions and above all, and this is Strogatz’s greatest strength, how it is applied to the solution of a wide range of very diverse problems in an equally wide and diverse range of topics.

 

[1] For a detailed analysis of Newton’s rejection of analytical methods in mathematics then I heartily recommend, Niccolò Guicciardini, Reading the Principia, CUP, 1999, but with the warning that it’s not an easy read!

 

16 Comments

Filed under Book Reviews, History of Mathematics

The role of celestial influence in the complex structure of medieval knowledge.

My entire life has followed a rather strange and at time confusing path that bears no relationship to the normal career path of a typical, well educated, middle class Englishman. It has taken many twists and turns over the years but without doubt one of the most bizarre was how I got to know historian of astrology Darrel Rutkin. We met on a bus, when he a total stranger commented that he knew the author of the book that I was reading, Monica Azzolini’s excellent, The Duke and the Stars: Astrology and Politics in Renaissance Milan. You can read the story in full here. At the time Darrel was a fellow at the International Consortium for Research in the Humanities: Fate, Freedom and Prognostication. Strategies for Coping with the Future in East Asia and Europe in Erlangen, where he was working on his book on the history of European astrology. Darrel and I became friends, talking about Early Modern science and related topics over cups of coffee and he twice took part in my History of Astronomy tour of Nürnberg. Before he left Erlangen he asked me if I would be interested in reading and reviewing his book when he finished writing it. I, of course, said yes. Some weeks ago I received my review copy of H. Darrel Rutkin, Sapientia Astrologica: Astrology, Magic and Natural Knowledge, ca. 1250–1800: I.Medieval Structures (1250–1500): Conceptual, Institutional, Socio-Political, Theologico-Religious and Cultural and this is my review.

Rutkin001

As should be obvious from the impressive title this is not in anyway a popular or even semi-popular presentation but a very solid piece of hard-core academic research. What I have, and will discuss here, is just volume one of three, which weighs in at over six hundred pages. In his work Rutkin present two theses the first of which he explicates in Volume I of his epos and the second of which forms the backbone of the two future volumes. The central thesis of Volume I is summed up in the slightly intimidating twelve-word term “astrologizing Aristotelian natural philosophy with its geometrical-optical model of celestial influences.” A large part of the book is devoted to constructing this object and I will now attempt to produce a simplified description of what it means and how it operated in medieval Europe.

It is common in the history of astrology to treat it as a separate object, as if it had little or nothing to do with the rest of the contemporary knowledge complex. It is also very common to lump astrology together with magic and the other so-called occult sciences. For the High Middle Ages, the period that his book covers, Rutkin rejects both of these approaches and instead proposes that astrology was an integral and important part of the accepted scientific knowledge of the period. His book is divided into five sections each of which I will now outline.

The first section is an eighty-nine-page introduction, which contains a detailed road map of the author’s intentions including a brief summary of what he sees as the current situation in various aspects of the study of the subject under investigation. This also includes an excursion: Astrological Basics: Horoscopes and Practical Astrology. This section is not based on the author’s own work but on that of Roger Bacon, one of the central figures of the book, so if you want to know how a leading medieval astrologer set up and worked with a horoscope then this is the right place to come.

The first section of the book proper deals with the relationship between astrology and natural philosophy in the thirteenth century and it is this section that defines and explains our intimidating twelve-word term from above. Rutkin’s analysis is based on four primary sources; these are an anonymous astrological text the Speculum Astronomiae, written around 1260 and often attributed to Albertus Magnus, an attribution that Rutkin disputes, the writings of Albertus Magnus (before 1200–1280), those of Thomas Aquinas (1225–1274) and those of Roger Bacon (ca. 1220­–1292), as well as numerous other sources from antiquity, and both the Islamic and Christian Middle Ages. In this first section he first presents those writings of Aristotle that contain his thoughts on celestial influence, which form the philosophical foundations for the acceptance of astrology as a science. He then demonstrates how the Speculum Astronomiae, Bacon and Albertus expanded Aristotle’s thoughts to include the whole of horoscope astrology and imbedded it into medieval Aristotelian natural philosophy, this is our “astrologizing Aristotelian natural philosophy.” He also shows how Thomas, whilst not so strongly astrological, as the others, also accepts this model. The technical astrology that is considered here is a highly mathematical, read geometrical, one based on the radiation theories of the Arabic scholar al-Kindi in his De radiis stellarum, as originally introduced into European thought by Robert Grosseteste (1175–1253) in his optical theories and adopted by Bacon. This explains how every geographical point on the earth at every point in time has a unique horoscope/astrological celestial influence: the “geometrical-optical” part of our intimidating twelve-word term. This also ties in with Aristotle’s geographical theories of the influence of place on growth and change. What comes out of this analysis is an astrological-geographical-mathematical-natural philosophical model of knowledge based on Aristotle’s natural philosophy, Ptolemaeus’ astronomy and astrology, and al-Kindi’s radiation theory at the centre of thirteenth century thought.

Rutkin does not simple state an interpretation of Albertus’, Bacon’s or Aquinas’ views but analyses their actual writings in fine detail. First he outlines one step in a given thought process then he quotes a paragraph from their writings in English translation, with the original in the footnotes, including original terms in brackets in the translation if they could possible be considered ambiguous. This is followed by a detailed analysis of the paragraph showing how it fits into the overall argument being discussed. He proceeds in this manner paragraph for paragraph cementing his argument through out the book. This makes hard work for the reader but guarantees that Rutkin’s arguments are as watertight as possible.

The second section of the book proper deals with the subject of theology, a very important aspect of the medieval knowledge complex. Rutkin shows that both Albertus and Thomas accepted astrology within their theology but were careful to show that celestial influence did not control human fate, providence or free will these being the dominion of their Christian God. This is of course absolutely central for the acceptance of astrology by Christian theologians. Bacon’s attitude to astrology and theology is completely different; he builds a complete history of the world’s principle religions based on the occurrence of planetary conjunctions, explaining why, as a result, Christianity is the best religion and addressed to the Pope, for whom he is writing, how one needs to combat the religion of the Anti-Christ.

The third section of the book proper now turns to the vexed question of the relationship between astrology and magic. Rutkin shows that both the Speculum Astronomiae and Albertus in his writing accept that astrology can be used to create magical images or talisman for simple tasks such as killing snakes. However, this is the limit of the connection between the two areas, other aspects of magic being worked by evil spirits or demons. Thomas, not surprisingly rejects even this very circumscribed form of astrological magic regarding all of magic to have its roots in evil. Bacon is much more open to a wider range of connections between the areas of astrology and magic.

Having set up the place of astrology in the medieval knowledge complex of the thirteenth century, the fourth and final section of the book proper takes brief looks at the evidence for its use in various fields within Europe in the period up to 1500. Fields sketched rather than covered in great detail included mathematics, medicine, teaching in the various faculties at the universities, annual prognostications at the universities and to close astrology in society, politics and culture.

Does Rutkin succeed in proving his central thesis for this his first volume? History is not like mathematics and does not deliver conclusive proofs but Rutkin’s thesis is argued in great detail with an impressive array of very convincing evidence. His work is rock solid and anybody wishing to refute his thesis is going to have their work cut out for them. That is not to say that with time, new research and new evidence his thesis will not undergo modification, refinement and improvement but I think its foundations will stand the test of time.

His second main thesis, which will be presented in the two future volumes of his work, is to explain how and why the medieval, mathematics based (read mathematical astrology), Aristotelian natural philosophy that had been created in the High Middle Ages came to replaced by a very different mathematics based, system of natural philosophy in the seventeenth and eighteenth centuries. Having ploughed my way through Volume I, I very much look forward to reading both future volumes.

It goes without saying that the book has an impressively long bibliography of both primary and secondary sources that the author has consulted. I consider myself reasonably well read on the history of European astrology but if I were to sit down and read all of the new, interesting titles I discovered here, I would be very busy for a number of years to come. There is also a first class index and I’m very happy to report that the book also has excellent footnotes, many of which I consulted whilst reading, rather than the unfortunately ubiquitous endnotes that plague modern publishing.

Before I move to a conclusion I wish to point out a second way to read this book. As it stands this is not a book that I would necessarily dump on an undergraduate or a historian, whose interest in the fine detail of Rutkin’s argument was peripheral but that is not necessary or at least not in its totality. I have already mentioned that the introduction contains a detailed road map to the whole volume and as well as this, each of the four sections has an introduction outlining what the section sets out to show and a conclusion neatly summarising what has been demonstrated in the section. By reading main introduction and the introductions and conclusions to the sections a reader could absorb the essence of Rutkin’s thesis without having to work through all of the documentary proof that he produces.

In general I think that Rutkin has set standards in the historiography of medieval astrology and that his book will become a standard work on the topic, remaining one for a long time. I also think that anybody who wishes to seriously study medieval European astrology and/or medieval concepts of knowledge will have to read and digest this fundamental and important work.

I’m posting this today, having pulled it up from the back of a list of planned blog posts because today Darrel’s book is being formally presented at the University of Venice, where he is currently working in a research project, this afternoon with Monica Azzolini as one of those discussing the book and so a circle closes. I shall be there with them in spirit.

69645207_10156641241176332_1790148631035117568_o

 

 

8 Comments

Filed under Book Reviews, History of Astrology, Uncategorized

A book for lunatics

The world has currently gone moon crazy, because it is now fifty years since a couple of American went for a walk on the moon. This has meant the usual flood of books, journal, magazine and newspaper articles, blog post and, Twitter and Facebook postings that now accompany any such #histSTM anniversary that is considered by the media world to be significant enough. With the following statement I shall probably lose half of my Twitter following overnight but personally I don’t find this particular anniversary especially interesting. I do have one peculiar biographical quirk in that I don’t think I actually watched that first moon landing; at least I have absolutely no memory of having done so. The last weeks of the school year 1968–69 were a highly emotional time for me. I had just been expelled from boarding school but was still living there as my fees were paid up to the end of the school year and my parents were away on sabbatical in Indonesia. Somehow all of that was more important in my life than some guys going for a walk on the moon.

Although I have skimmed the occasional newspaper/magazine/Internet article I have not and will not bother to buy and read any of the apparently X zillion books that have been thrown onto the market to celebrate the occasion. I will admit to having treated myself to Ewen A. Whitaker’s Mapping and Naming the MoonA History of Lunar Cartography and Nomenclature (CUP, ppb. 2003), which actually has little to do with the actual anniversary. I have however acquired and read one book written specifically for the anniversary Oliver Morton’s The Moon: A History for the Future (The Economist Books, 2019). I got this for free because I read and suggested corrections for those bits of the book dealing with the Early Modern Period. Although, I saved the author from making, what I consider to be a serious error but which the normal reader probably wouldn’t even have noticed, I think my contribution to the final product was so minimal that I can safely review it without fear of personal bias.

Morton001

We’ll start at the top with the very simple statement; this is truly an excellent book. I would be very tempted to say, if you only read one book on the moon this year then you could do worse than choose this one. However, not having read any of the others, this would not be very fair to the other moon book authors. Back to the praise, Morton’s book is a wonderful literary tour de force, which is also incredibly informative. He combines the histories of astronomy, technology, the moon landings and science fiction to create a stimulating potpourri of lunar lore and selenology.

The book is divided into eight sections rather than chapters, each of which deals with a different aspect of humanity’s relationship with the Moon. Section I introduces the reader to the phenomenon of earthshine, the light reflected from the Earth that illuminates those parts of the Moon not lit by the Sun, both its discovery in the Early Modern Period and its use in modern times for scientific experiments. Section II deals with studies of the Moon’s appearance from the High Middle Ages down to the twentieth century. Section III takes us along the path of the development of rocketry up to Apollo and then with Armstrong, Aldrin and Collins on Apollo 11 to that first ever moon landing. Section IV takes a look at the various theories to explain the origins of the Moon and its geology. Section V deals with the end or better said the collapse of the Apollo program and then over the years the various suggestions for economically viable schemes to return to the Moon, here Morton demonstrates his strengths as a narrator. Although he is obviously a space fan he carefully details why such schemes were largely unrealistic or impractical. Section VI examines the various schemes currently being developed for a real return. Having got there, section VII discusses what to do when we get there if we do go back. Section VIII looks at negative literary depictions of the Moon illustrating rather nicely that maybe the Moon isn’t such an attractive place to visit.

This listing of the main themes of each section doesn’t do Morton’s inventiveness justice. He weaves lots of side topics into the weft of his main narratives taking his readers down many highways and byways, leaving the readers with the impression that he has consumed a vast library of lunar information, an impression strengthened by the extensive bibliography.  His real achievement is to pack so much fascinating information into so few pages, whilst retaining a wonderful light readable style. His book is both an encyclopaedia and a work of art.

 

 

4 Comments

Filed under Book Reviews, History of Astronomy, History of science, History of Technology

Mathematics or Physics–Mathematics vs. Physics–Mathematics and Physics

Graham Farmelo is a British physicist and science writer. He is the author of an excellent and highly praised biography of the British physicist P A M Dirac, The Strangest Man: The Hidden Life of Paul Dirac, Quantum Genius(Faber and Faber, 2009), which won a couple of book awards. He is also the author of a book Winston Churchill role in British war time nuclear research, Churchill’s Bomb:A hidden history of Britain’s first nuclear weapon programme (Faber and Faber, 2014), which was also well received and highly praised. Now he has published a new book on the relationship between mathematics and modern physics, The Universe Speaks in Numbers: How Modern Maths Reveals Nature’s Deepest Secrets (Faber and Faber, 2019).

25703.books.origjpg

I must admit that when I first took Farmelo’s new book into my hands it was with somewhat trepidation. Although, I studied mathematics to about BSc level that was quite a few years ago and these days my active knowledge of maths doesn’t extend much beyond A-Level and I never studied physics beyond A-Level and don’t ask what my grade was. However, I did study a lot of the history of early twentieth century physics before I moved back to the Renaissance. Would I be able to cope with Farmelo’s book? I needn’t have worried there are no complex mathematical or physical expressions or formulas. Although I would point out that this is not a book for the beginner with no knowledge; if your mind baulks at terms like gauge theory, string theory or super symmetry then you should approach this text with caution.

The book is Farmelo’s contribution to the debate about the use of higher mathematics to create advanced theories in physics that are not based on experimental evidence or even worse confirmable through experiment. It might well be regarded as a counterpoint to Sabine Hossenfelder’s much discussed Lost in Math: How Beauty Leads Physics Astray(Basic Books, 2018), which Farmelo actually mentions on the flyleaf to his book; although he obviously started researching and writing his volume long before the Hossenfelder tome appeared on the market. The almost concurrent appearance of the two contradictory works on the same topic shows that the debate that has been simmering just below the surface for a number of years has now boiled over into the public sphere.

Farmelo’s book is a historical survey of the relationship between advanced mathematics and theoretical physics since the seventeenth century, with an emphasis on the developments in the twentieth century. He is basically asking the questions, is it better when mathematics and physics develop separately or together and If together should mathematics or physics take the lead in that development. He investigated this questions using the words of the physicists and mathematicians from their published papers, from public lectures and from interviews, many of which for the most recent developments he conducted himself. He starts in the early seventeenth century with Kepler and Galileo, who, although they used mathematics to express their theories, he doesn’t think really understand or appreciate the close relationship between mathematics and physics. I actually disagree with him to some extent on this, as he knows. Disclosure: I actually read and discussed the opening section of the book with him, at his request, when he was writing it but I don’t think my minuscule contribution disqualifies me from reviewing it.

For Farmelo the true interrelationship between higher mathematics and advanced theories in physics begins with Isaac Newton. A fairly conventional viewpoint, after all Newton did title his magnum opus The Mathematical Principles of Natural Philosophy. I’m not going to give a decade by decade account of the contents, for that you will have to read the book but he, quite correctly, devotes a lot of space to James Clerk Maxwell in the nineteenth century, who can, with justification, be described as having taken the relationship between mathematics and physics to a whole new level.

Maxwell naturally leads to Albert Einstein, a man, who with his search for a purely mathematical grand unification theory provoked the accusation of having left the realm of experiment based and experimentally verifiable physics; an accusation that led many to accuse him of having lost the plot. As the author of a biography of Paul Dirac, Farmelo naturally devote quite a lot of space to the man, who might be regarded as the mathematical theoretical physicist par excellence and who, as Farmelo emphasises, preached a gospel of the necessity of mathematically beautiful theories, as to some extent Einstein had also done.

Farmelo takes us through the creation of quantum mechanics and the attempts to combine it with the theories of relativity, which takes the reader up to the early decades following the Second World War, roughly the middle of the book. Here the book takes a sharp turn away from the historical retelling of the emergence of modern theoretical physics to the attempts to create a fundamental theory of existence using purely mathematical methods, read string theory, M theory, supersymmetry and everything associated with them. This is exactly the development in modern physics that Hossenfelder rejects in her book.

Farmelo is very sympathetic to the mathematicians and physicists, who have taken this path but he is in his account very even handed, letting the critics have their say and not just the supporters. His account is very thorough and documents both the advances and the disappointments in the field over the most recent decades. He gives much emphasis to the fruitful co-operations and exchanges that have taken place between mathematicians and theoretical physicists. I must say that as somebody who has followed the debate at a distance, having read Farmelo’s detailed account I came out of it more sympathetic to Hossenfelder’s standpoint than his.

As always with his books Farmelo’s account is excellently researched, much of the more recent material is based on interviews he conducted with the participants, and very elegantly written. Despite the density of the material he is dealing with, his prose is light and often witty, which makes it easier to grapple with the complex themes he is discussing. I would certainly recommend this book to anybody interested in the developments in modern theoretical physics; maybe to be read together with Hossenfelder’s volume. I would also make an excellent present for any young school leaver contemplating studying physics or one that had already started on down that path.

22 Comments

Filed under Book Reviews, History of Mathematics, History of Physics

The Copernican Revolution 101

This is a review of a book that is intended to deliver what the post title implies, Todd Timberlake and Paul Wallace, Finding Our Place in the Solar System: The Scientific Story of the Copernican Revolution (CUP, 2019).

Timberlake001

The book was developed as a textbook for a course–Astronomy 120: The Copernican Revolution–which Todd Timberlake teaches as a science requirement for students majoring in non-scientific fields at Berry College in Georgia (USA). The course was originally taught by Paul Wallace and when he left Berry College, Todd Timberlake, an astronomer and physicist, took over the course using Wallace’s teaching material, hence the double authorship. It will come as no surprise that I very much support the idea of introducing students to science through its history, as is done here. Timberlake is an astronomer and not a historian so the emphasis is very much on the scientific content and less on the context in which it developed but he includes potted biographies of the main figures involved.

After a brief introduction on the nature of science and the evolution of scientific knowledge, which is well done, Timberlake moves on in the next three sections of the book to explaining how the ancient picture of the cosmos developed introducing all of the astronomical terminology as he progresses. This is excellently done but I do have one minor objection. In basic astronomy there is a lot of terminology that is not part of everyday language, to start with there are three different coordinate systems for locating objects in the heavens. I have read numerous accounts of all this over the years and I still sometimes get confused and I find a glossary of the technical terms very useful for a quick check, this book doesn’t have one.

What the book does have is at the end of each section a short chapter titled Reflections on science, a sort of philosophy of science light. Having actually studied philosophy of science with some first class teachers I was prepared to be highly sceptical of these but they are actually very well done and add, in my opinion, a lot to the value of the book as a teaching text.

The next sections of the book, each of which consists of five or six short chapters, deal successively with Copernicus, Tycho Brahe, Kepler, Galileo and Newton. Mainlining the mainstream figures, which despite my own love of the minor and oft unheralded contributors, is OK for what is intended as an introductory text. I was particularly impressed with his sensitive and sympathetic treatment of Kepler’s, quite frankly, totally bizarre cosmological heuristic. The tenth and final section of the book is titled, Confirming Copernicus: evidence for Earth’s motion, which takes the reader in quick short steps down to the nineteenth century. The book closes with twenty short appendices that present to mathematics of the various historical developments, which had been largely left out of the main texts.

The book has extensive endnotes that are mostly references to the equally extensive and comprehensive bibliography. There is also a detailed and extensive index.

Timberlake writes well and lucidly. His text is easy to read and his explanations are clear and straightforward. He covers the material well and I on the whole would thoroughly endorse his book as an excellent textbook and introduction to the history of European astronomy.

There are several minor historical errors in the potted biographies that I shall leave without comment, as to do so would make this review appear more negative than it should. However there is one major historical falsehood that I simply cannot and will not ignore. Having delivered a good account of ancient Geek astronomy Timberlake has a section titled, Astronomy and cosmology after Ptolemy. The third sentence of this section reads as follows:

The rise of Christianity in Europe led to the neglect of mathematical astronomy, and of the “pagan” knowledge of the ancient Greeks and Romans generally. At the same time astronomy flourished in the Arabic world. Many Greek astronomical and philosophical works, including the Almagest and Planetary Hypotheses, were translated into Arabic. (p. 96)

This is of course the classic ‘Christianity killed ancient science’ myth, which in the year 2019 should not be part of a college level historical textbook. Let us examine the facts one more time. Classical Greek learning began to decline in the ancient world from the middle of the second century CE due to a general socio-political and cultural decline, which had absolutely nothing to do with the rise of Christianity. It had basically disappeared in the Western Empire (Europe) by the end of the fifth century CE. The only places, within the Western Empire where it survived, was within the Christian monasteries, which preserved a modicum of the classical learning. The late encyclopaedists such as Boethius and Isidore, who rescued what could still be rescued, were Christians. The Islamic Empire did not begin to appropriate Greek knowledge until the eighth century CE. Their first sources of Greek scientific and philosophical works were those that had been translated into Syriac by Nestorian Christians, within the Persian Empire. Their second, and major, source was Byzantium, the Eastern Empire, which was Christian. By the eighth century there began the first low level returns of Greek astronomical knowledge into Europe during the Carolingian Renaissance in the form of calendrical and computus studies. Christianity didn’t neglect Greek astronomy it played a leading role in conserving and transmitting it during a period of general cultural collapse[1].

A second historical howler, that I can’t ignore, is not as important as his propagation of the classic Christianity killed ancient science myth and in fact I’m not sure whether it should make me laugh or cry. He points out correctly that the heliocentric system establishes a relative measure of the planetary orbits based on the average distance between the Earth and the Sun, the Astronomical Unit of AU. (p.126) To this he adds the following footnote:

Copernicus did not in fact, use the Astronomical Unit in this way, but modern astronomers do. Copernicus typically assigned some large number (say 10,000) of undefined units to the Earth-Sun distance and then found the radii of the planetary orbits in terms of these units. He used a large number in order to avoid having to deal with fractions –or decimals, which did not come into common use until after the French Revolution. [my emphasis]

Decimals were known and used both in Chinese and Arabic mathematics before they entered Europe. The first European author to introduce decimals was Simon Stevin in his De Thiende published in Dutch in 1585 and translated into French as Disme and English as Decimal Arithmetic. Stevin’s system of decimals did not use the decimal point, which was introduced by Christoph Clavius or by Bartholomaeus Piticus in his trigonometrical tables. Decimals were in common use throughout the seventeenth century particularly in both trigonometrical and logarithmic tables. I can only surmise that Timberlake is confusing decimals with the metric system.

As already stated above, Timberlake’s book is an excellent entry level introduction to the history of European mathematical astronomy as well as serving as an introduction to the process of science for non scientists and anybody looking to teach themselves or looking for a textbook for an advanced school class or a college level course should definitely consider using this volume and at an official retail price of just £29.99 for an excellent produced hardback it should be well within the buying power of the average student.

 

[1]For details read Stephen C. McCluskey, Astronomies and Culture in Early Medieval Europe, CUP, ppb. 2000 and Dimitri Gutas, Greek Thought, Arabic Culture: The Graeco-Arabic Translation Movement in Baghdad and Early ‘Abbāsid Society (2nd–4th/8th–10thcenturies), Routledge, ppb. 1998.

6 Comments

Filed under Book Reviews, History of Astronomy, Renaissance Science

An open letter to an author

Dear Yuval,

if I may? Sometime around the publication in English of your trendy mega bestseller, Sapiens, I read something from you, I can’t remember if it was an essay or an extract from the book, on the Scientific Revolution, as part of the extensive sales campaign for your publication. To say the least, I was, to put it mildly, totally underwhelmed and decided that I really didn’t need to read your book. Since then whenever the subject of your book came up in conversations or on the Internet I made disparaging comments about your abilities as a historian of Early Modern science. Recently it occurred to me that I might be being somewhat unfair, my comments being based on a half remembered short piece of writing and that maybe I ought to give you a second chance. Eventually I ordered your book through interlibrary loan, my university library apparently doesn’t have a copy. When it arrived I sat down to read the Fourth Section of the book entitled The Scientific Revolution. You must excuse me but I have so much that I want to read that I don’t really have time to read your whole book.

The first page of waffle about time travelling peasants and battleships didn’t really impress me but then on the second page I stumbled across the following:

In 1500, few cities had more than 100,000 inhabitants. Most buildings were constructed of mud, wood and straw; a three-story building was a skyscraper. The streets were rutted dirt tracks, dusty in summer and muddy in winter, plied by pedestrians, horses, goats, chickens and a few carts. The most common urban noises were human and animal voices, along with the occasional hammer and saw. At sunset, the cityscape went black, with only an occasional candle or torch flickering in the gloom.

The evocative picture that you paint with your words in this paragraph reminds me of the Hollywood B-movie visions of medieval hovels and unwashed peasants that informed my childhood and in my opinion has about as much truth content as those movies of yore.

I am a historian of Renaissance science, hence the name of this blog, and I live just up the road from the German, Renaissance city of Nürnberg, where, belonging as I do the an active group of local historians, I conduct on a fairly regular basis guided tours of the history of astronomy of that city most, but not all, of which revolves around the year 1500, plus or minus 50 years. For your edification and education I would now like to take you on part of that tour to show what a Middle European city really looked like in 1500.

Before I start I will grant that few European cities had more than 100,000 inhabitants; Nürnberg, then the second biggest German city, only had a population of 40,000. Of course there were much bigger cities in other parts of the world, Middle East, India, China but as the entire world population has been estimated to lay between 400 and 500 million in 1500, it is not surprising that the major cities were much smaller than those of today. Scaling up proportionally a city of 40,000 in 1500 with a world population of 500 million is equivalent to a city of more than 500,000 in today’s world of 7,000 million inhabitants, slightly less than Nürnberg’s current population.

I always start my tour with this sundial, which was created in 1502.

station_16a_k

Lorenzkirche Sundial Source: Astronomie in Nürnberg

As you can see it is a quite sophisticated sundial and if you know how, you can read the time on it in three different ways, from sunrise, from midday and according to the Great Nürnberger clock: a system between the medieval local time system and our equinoctial hours: A bit beyond the primitive culture that you sketch. I hear you muttering but what about clocks. We’ll get to one of those a bit later.

The sundial is on the side of the Lorenzkirche, one of Nürnberg’s two parish churches started in 1250 and finished in 1477.

Nürnberg St. Lorenz Türme von Westen

Source: Wikimedia Commons

As you can see it’s a rather impressive sandstone building with a slate roof, as were most of the city buildings in 1500. By the way, the streets were also paved. No dirt tracks here.

Our next station is the Heilige-Geist-Spital built in 1399 as an old peoples residence, a function it still fulfils today.

Heilig-Geist-Spital_abends

Heilige-Geist-Spital Source: Wikimedia Commons

Moving on, we come to the Market Place and the Frauenkirche built between 1352-1362.

Nuremberg,_Hauptmarkt_and_Frauenkirche_4685

Frauenkirche Source: Wikimedia Commons

The mechanical clock on the facade was built in 1509.

MK40639_Kunstuhr_Frauenkirche_(Nürnberg)

Source: Wikimedia Commons

The ball above the clock shows the phases of the moon, still accurate today. At twelve-noon everyday there is a complex mechanical display with fanfares by the trumpeters, drum rolls and bell ringing. This is followed by the seven Electors circling the Emperor in the middle, three times. Tourists from all over the world come to Nürnberg to witness this spectacle.

I like this 19th-century picture showing the Schöner Brunnen (Beautiful Fountain), also on the Market Place, which was built between 1385-1396.

DnHIZRmW0AAm9kT.jpg-large

Here it is in all its glory, today.

1024px-Nuernberg-schoener-Brunnen-gp

Schöner Brunnen. In the backgrounfd you can see the towers of the other parish church St. Sebald (14th century) Source: Wikimedia Commons

You might like this house, it was the home of a local artisan, Albrecht Dürer (1471–1525), you might have heard of him?

ADH_Tiergärtnertorpl

Source: Wikimedia Commons

In 1500, Nürnberg was a major industrial city, producing a very wide range of metal products, as well as being a leading European trading centre. In fact it was one of the biggest centres in Europe for the production of everything that could be made out of metal. For example, the Nürnberg craftsmen received an order from the Emperor, Charles V (1500–1558), for five thousand suits of armour, so we can assume that there was quite a lot of noise on the streets on the city. Nürnberg traded on a large scale with much of Europe. It was not unusual for the traders to attend the Frankfurter Fair with a waggon train of five hundred waggons

You can get a good overall impression of the city from this illustration out of the Schedelsche Weltchronik (known in English as the Nuremberg Chronicle), the world’s first printed encyclopaedia, printed and published in Nürnberg in 1493.

nuremberg_chronicles_-_nuremberga

Nürnberg as depicted in the Nuremberg Chronicles 1493

By now I hope you will realise that the real historical Nürnberg in 1500 was radically different from your fairy tale description of a city in 1500. Having recovered from having read the paragraph reproduced above, I tried to persevere with your book but having come across several more equally dubious paragraphs in the next few pages, I must honestly say that I can’t be bothered. I have better things to do with my time. I can’t claim that this is a review of your book but I certainly won’t be recommending it to anybody, anytime soon.

No hard feelings

Thony

 

 

 

 

 

 

 

 

19 Comments

Filed under Autobiographical, Book Reviews, Uncategorized