"Science and Islam" by Ehsan Masood

An accessible and enlightening survey of Islamic science during the so-called Dark Ages and beyond

"Animals engage in a struggle for existence [and] for resources, to avoid being eaten and to breed...Environmental factors influence organisms to develop new characteristics to ensure survival, thus transforming into new species. Animals that survive to breed can pass on their successful characteristics to [their] offspring."

Is this Richard Dawkins writing in the 21st Century? Or Lamarck in the 19th? Or some godless renegade in 17th Century Europe? Not even close. The author is al-Jahiz, a science writer from 9th Century Baghdad. The surprising thing is not that an Islamic author could write such a thing so early, but that we are surprised to learn that he could -- that's what Ehsan Masood would say, at any rate. And readers of Science and Islam will probably agree with him by end of this lively and user-friendly book on Islamic science during the so-called Dark Ages and beyond.

Part 1 of the book mixes a potted history of Islam with descriptions of the patrons, institutions and practitioners of science in each major regime from 700AD to 1300AD. The story is long but compactly told. In the space of four chapters and seven centuries, Islamic science flowers in Damascus, Baghdad, and Egypt before being cut down by the Mongols and Tartars. Along the way Masood sketches some of the many colourful figures of the time, like the bird-man ibn-Firnas and the scientific advisor who is unable to build a damn on the Nile and feigns madness to avoid the wrath of his caliph.

Part 2 hones in on the science of this "staggering renaissance." Masood covers medicine, astronomy, mathematics, chemistry, and engineering, in that order, with a post-script on evolution, optics, and Islamic universities. When describing the heroes of Islamic science and their remarkable work, Masood keeps one eye on their Greek heritage and another on their European successors. Comparisons are odious, but illuminating: Islamic scientists are all the more impressive when we learn that they questioned Galen on medicine, challenged Ptolemy on cosmology, and made direct contributions to the work of Copernicus, Kepler, Fermat, Newton, and the engineers of the industrial revolution.

Part 3 looks at Islamic science in the 19th and early 20th century, and draws some lessons for the future. This is not just an epilogue. It asks what the scientific revolutionaries of the 17th Century thought about Islamic science, whether the Ottomans were wise to borrow from Western science in the 19th Century, and whether imperialist science was a good thing for India. These are all delicate questions with ambiguous answers, and Masood gives a balanced survey. To end, he picks up a thread that runs right through the book, the violence of pro-science Islamic rulers. "If science is to return to the nations of Islam," Masood concludes, "it must do so without interfering with people's freedom to believe."

This conclusion is wrong if taken too literally. Surely a belief in evolution (for example) will interfere with a person's freedom to believe that the earth was created 6000 years ago -- and rightly so. Still, Masood does well to remind us that dictatorial rule does not help the cause of science, even if the dictator is pro-science. This book also reminds us of another easy-to-forget truth: for most of its history, Islamic science flourished alongside the teachings of Muhammad, not in spite of them -- and sometimes, as for medicine, it flourished because of those teachings.

Science and Islam has some gaps. Sometimes Masood left me hanging after skipping past what seemed to be key achievements in Islamic science. One is the passage quoted at the top of this review, which summarises not just evolution but also a mechanism for evolution that resembles evolution by inherited characteristics; another is the controlled clinical trial conducted by the medic al-Razi to test the theory of bloodletting. Clinical trials and evolution are such monuments of modern science that I expected Masood to say more about their role in Islamic science. Also, Islamic science from 1300 to 1800 gets little attention -- which is fine for such a small book, but Masood does not explain the omission.

Topics that require equations or diagrams are not well-covered. When it comes to Islamic optics Masood gives 4 pages to theories of sight -- which are easy to describe qualitatively -- and only 2 paragraphs to refraction, reflection, and other theories of how light travels. The chapter on number gives a good survey of Islamic mathematicians but is light on algebra, perhaps their most important contribution in this field. A diagram or two in the chapter on astronomy may have clarified concepts such as the "Tusi couple", a mathematical tool for simplifying Ptolemy's model of the heavens. However, in place of technical detail the book has up-to-date scholarship, an asset for understanding the Islamic influence on Copernicus, the water clocks of al-Jazari, and numerous other topics.

Science and Islam faces the dual challenge of covering a technical subject (science) and a neglected period of history (the East during the Dark Ages). The book is aimed at a general audience, the majority of which will be unfamiliar with one or both of these topics. Masood answers both challenges well. His smooth prose and bite-sized format are easy on the novice palate (there is a new sub-chapter every 2 pages or so). All but the most learned readers will come away with their image of both science and Islam refreshed.

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Review of "Lords of the Fly" by Robert E. Kohler

A fine book about flies and scientists

Robert E. Kohler. Lords of the Fly: Drosophila Genetics and the Experimental Life. University Of Chicago Press, 1994.

First of all, Lords of the Fly is an excellent book. It is readable, thorough, vivid and original. It contains enough technical detail to guide the reader, but not too much to confuse him. It describes, in a novel way, an important and much-studied period in the history of biology: the rise of genetics in the first half of the century. It contains considerable detail about the everyday working lives of the “Drosophilists,” the men and women who worked with the fruit fly Drosophila. But it always tries to link those details to the actual science they produced. “I hope to persuade the readers of this book,” writes Kohler, “that experimental sciences have been shaped by their material cultures.” Kohler succeeds.

The challenge is to explain that success. What lessons does the book contain for those who would write laboratory-based histories of science? One lesson is that comparison works. Kohler uses the comparative approach to illuminate two separate but similar historical episodes: the early years of research based on Drosophila, led by T.H. Morgan at Columbia University; and the work, led by Beadle, on Neurospora.

Kohler also shows that structure works. Throughout the book, Kohler treats Drosophilia and the Drosophilists in three different ways: as technological devices, with the Drosophilists manipulating their flies to create scientific instruments; as an episode in natural history, with the human and animal organisms migrating, specialising, adapting, selecting; and as an example of a “moral economy,” a human community with a set of values, procedures, and penalties. These themes serve as a map, opening up a field of inquiry and setting its elements into clear array.

Kohler also makes good use of metaphor and analogy. At times her analogy between experimental life and ecological life is merely decorative. But often it is illuminating, casting descriptive and explanatory light. For example, he writes: “Intragroup conflict, by isolating Dobzhansky from the traditional practice of his American colleagues, cleared the way for the rapid evolution of a new species of experimental practice.”

The subtitle of the book is a nod to Steven Shapin and Simon Schaffer's Leviathan and the Air Pump, the ground-breaking study of experimental science in the seventeenth century. Kohler only takes what he needs from Shapin and Schaffer, which is an interest in the details of experimental practice. He does not pick up Shapin and Schaffer's task of pricking the pretensions of scientists. By showing (for example) that Morgan and his students “constructed” a new fly by manipulating its genotype, Kohler means to show how scientists work, not to challenge the integrity of their results. In one sense this approach limits the force of Kohler's book, since he does not enable himself to explain the resolution of disputes about ultimate results. But it also opens up room to explain many other features of experimental life, such as choices of research topics, the pace of research, the harmony or otherwise of the “moral economy,” and the failure of interdisciplinary efforts.

Sometimes Kohler pushes his aims too hard. He suggests, for example, that material practices were the “controlling factor” in the rapid expansion of Dobzhansky's project of mapping the phylogenies of naturally occurring Drosophila pseudoobscura. From Kohler's account, however, it seems that a theoretical breakthrough (the discovery of a link between phylogenetic maps and chromosomal inversions) was just as important. Also, one might protest that Kohler does not fully capture the amount of repetition and long-term drudgery that was involved in processing Drosophilia. But the reader gets glimpses of this aspect, as in Dobzhansky slaving over mounds of flies. Kohler might have turned the glimpses into a full view by including more technical detail and literary evocation. But those two features are not on the book's agenda. As for Kohler's actual aims, he meets them in style.

Lords of the Fly on Amazon

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"Representing Electrons" by Theodore Arabatzis

An ambitious and pretty successful biography of the electron

Theodore Arabatzis, Representing Electrons: A Biographical Approach to Theoretical Entities. Chicago and London: The University of Chicago Press, 2006

In Representing Electrons, Theodore Arabatzis gives a detailed account of scientific inquiry into the electron, covering roughly the years 1891-1824. The main message is that scientific entities have a "life of their own": they can act independently of theory, theoreticians, and experimenters. In delivering this message, Arabatzis makes a bold and largely successful attempt to bring the historical and philosophical approaches into a mutually stimulating relationship.

You can see Arabatzis’ dual interest in the history and philosophy in his choice of advisors and collaborators. While at Princeton University Arabatzis came into contact with the philosopher Bas van Fraassen, and numerous other philosophers are energetically deployed in the body of the book: Karl Popper, Larry Laudan and Thomas Nickels are quoted on the topic of “problem situations”, Paul Feyerabend and Ian Hacking on scientific realism, and Hilary Putman on theories of reference. Also featured in the author's acknowledgments are prominent historians of science, including Jed Buchwald, Warwick Taylor and Ernan McMullin.

In Representing Electrons, Arabatzis puts his multi-layered background to good use. Three themes dominate the book: realism and meaning change; the "discovery" of scientific entities; and the autonomy of theoretical entities. In Arabatzis's account, each of these themes has a historical and a philosophical dimension.

Take the topic of scientific discovery. Here, Arabatzis corrects the commonly-held view that J.J. Thomson “discovered” the electron. In doing so he uses the historian’s tools, probing scientists’ ideas through their scientific papers (such J.J. Thomson’s Cathode Ray article in Philosophical Magazine) and other writings (Lorentz’s Nobel Prize speech, for example. In later chapters he uses interviews conducted by Thomas Kuhn.) But this historical spade-work is guided by a philosophical discussion of “discovery” that draws on Hacking, Kuhn and Nickles. Here Arabatzis argues for the possibility of an account of discovery that is realism-neutral, and stresses the gradual, consensual nature of discovery: what we call “discoveries” are usually something more like “constructions.”

A similar pattern emerges in the next four chapters. Here, Arabatzis goes into considerable detail when dealing with the key episodes in the evolution of ideas about the electron, following the concept as it moves between various stages within physics (from classical to quantum and relativistic physics) and between disciplines (physics and chemistry). But his account is held together by the broad idea that the electron had a "life of its own," a capacity to throw up problems and suggest solutions.

Throughout the account, Arabatzis keeps a close eye on the stability of the "electron" concept through time and between practitioners. This conceptual stability comes to the fore in the concluding discussion about meaning change and realism in science. Arabatzis goes over some responses to Paul Feyerabend, who argued from meaning change to the non-existence of unobservable entities. When these responses fail, what is left for the realist? Arabatzis gives a two-fold answer. First, the case for realism can be supported by reference to the "writings" of the putative entity: if multiple observations give evidence of the same unobservable entity, you can be pretty sure the entity is real. Secondly, the case for realism can be supported by a historical account of a concepts' stability over time.

The final paragraph of the book draws out the implications of these arguments for historical accounts of the electron. Hence the attempted union of history and philosophy is carried right to the end of the book. Is this attempt successful? On the whole, the answer must be “yes.” There is a danger here of artificially gluing different disciplines together, but Arabatzis largely avoids this danger. The philosophical discussion in the concluding chapter draws on examples from the author’s historical account; during the historical discussion the reader is constantly reminded of the philosophical questions at hand; and the philosophy comments not only on the science of microphysics but also on the methodology of historians of physics.

One might complain that the philosophical discussion about realism and meaning change is independent of the “biographical approach” that Arabatzis takes to the electron. At least, Arabatzis seems to be in two minds about this. On the one hand, he pursues the “historicist” approach to discovery precisely because it does not require any prior commitment to realism or anti-realism: it keeps everyone happy. On the other hand, he writes the concluding chapter (on meaning-variance and realism) largely to justify his historical methodology: “for those who disbelieve in the existence of unobservable entities...a historical approach devoted to its representation may seem vacuous.”

In Arabatzis' defense, the final chapter does explore the implications of the historical account for the realism debate (not just the other way round). And his equivocation here may be just another sign that historians and philosophers (not just Arabatzis) have inconsistent aims. To a historian, who is worried about what happened in the past, the key criterion for existence of an entity is whether the entity was significant for past scientists. To a philosopher, the key criterion is whether it is, in fact, right to think that the entity exists. If Arabatzis is in two minds here, the problem does not lie with him, for being inconsistent, but with the two disciplines, for being different; Arabatzis' only real fault is not to clearly acknowledge this difference.

In the well-tilled field of historical research into the electron, novelty is crucial to a book’s success. The chief novelty in Representing Electrons is is the idea that concepts have a "life of their own." This idea does give rise to a fresh retelling of the atomic story: a vivid picture emerges of the electron standing on the outside of theory, teasing physicists into dead-ends and leading them on to unexpected new insights.

But Arabatzis has only given us a new picture insofar as he has applied it to a new entity: the ideas behind the picture are unexciting. For example, Arabatzis writes about Sommerfeld's selection rules, and how his “struggle to discipline the electron in a principled way ran into difficulties with its writings.” But do these metaphors convey anything more than the mundane fact that Sommerfeld had trouble matching his theory about the electron to his observations about it? A similar question may be asked about the fact that physicists found heuristic value of theories, and that they had trouble making the concept of the electron internally coherent. If the answers to these questions are “no”, this is not to say that there is no value in Arabatzis' biographical approach. It just means that the value lies in its contribution to the narrative structure of the book, and not to its philosophical depth.

One can always make quibbles about exposition, especially when an author tries to describe technical paths of reasoning. Overall Arabatzis does a good job here: a basic knowledge of maths is required to understand the derivations, but most of the discussion is within the reach of the ordinary reader. However, the book would benefit from more images of the relevant theories (eg. of atomic structure) and experimental results (especially spectral patterns). This would not just aid reader understanding. Copies of original diagrams of the electron would give a better idea of how physicists "represented" the electron to eachother and to themselves.

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Notes on ACAAPNZ 2008 II

A third selection from the 2008 annual conference of the NZ division of the Australasian Association of Philosophy

Tool Use and Life History of Early Homos. Ben Jeffares (ANU).

How to account for human cognitive and social evolution? One approach is to focus on the physical evidence of human evolution (skeletons, tools, drawings, etc.) and on the periods where this physical evidence indicates dramatic changes in human life, thought and behavior. This is Jeffares' approach, and in this talk he concentrated on a dramatic change in human tool use that seems to have taken place around 1.5 million years ago.

1.5mya is a hotspot for archaeologists because it's meant to be the great coming of age of our species – the point where we stopped being walking chimps and became hairy humans. And a jump in tool use is the main marker of this shift. Jeffares thinks tools were around well before the point where the first appear in the archaological record. Skeletal remains indicate that early bipeds had a hand structure suitable for tool-use well before 2.5mya. Be that as it may, tools became more refined around 1.5mya, being more symmetrical and sophisticated and more likely to be “time travellers”: made in advance and for repeated use.

How to account for this change? It's really quite interesting, but the evidence is fragmentary. Studies have suggested that homos started living differently around the time that tool-makers sharpened their act. The started having longer childhoods, longer periods of learning and maturing: the age of the teenager had begun. They also had patchier resources, had to kill away from home and in unknown places. So they had to plan ahead, making tools at home using secure resources. And, crucially, the children sat around while the tool-makers worked, and the tools lay around as well. Teaching ensured that any new skills or gizmos could be passed on. And the tools that lay around acted as “templates”, finished products that young killers could copy. As Jeffares put it, students could learn from “products”, not just from “behaviors.”

A nice story, but is it true? Jeffares is sensitive to the weaknesses of the evidence, and with good reason. It is not an exaggeraion to say that the extended-childhood data is based often based on “half a dozen teeth.” Human evolution is light on evidence and heavy on theorising – not necessarily a bad thing, and good for philosophers. There's some doubt about Jeffares' early tool-use thesis. Tools are not the only reason that manual dexteritry, of the kind found in skeletal remains, can arise. As Sterelny puts it, “it's always important to be able to scratch your bum.” Turning over rocks for food, extracting berries or flesh, forcing other animals to the ground: all would need precise and powerful grips.

Some will also question the inference from stone-crafting to tool-use. Some of the stones in question are beautifully symmetric, crafted beyond the needs of mere huntsmen. They have the look of ornaments, icons. Jeffares insists, though, that the elegant tear-drop stones are the exception. And there's no need to worry about the fact they have a sharp edge all the way round. True, this would make them inpracticable as hammers or weapons. But they were not always like that, says Jeffares. Whenever one edge wore out, our frugal ancestors worked on another edge of the same stone -- and so on until the stone was crafted all the way around. It's only the finished product we see.

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