'Elegance in Science'

Ian Glynn is a physiologist with a passion for a concept not usually associated with his field: elegance. Specifically, its application and relevance across a wide range of scientific disciplines, from physiology to physics, astronomy to neurology. In his new book, Elegance in Science: The Beauty of Simplicity (Oxford University Press), Glynn gives examples of elegance from each of these subjects and several others, showing how elegance crops up in places where it might be expected (in the mathematics and mechanics of Archimedes) and where it might not be (in the nerve fibers of a giant squid).

Glynn, professor emeritus of physiology at the University of Cambridge and a Fellow of Trinity College, Cambridge, spoke to Inside Higher Ed via e-mail, explaining his interest in elegance, how it applies to science -- and why scientists should care.

Q: How do you define “elegance” in the context of your book?

A: The dictionary definitions of elegant -- graceful, tasteful, of refined luxury -- are useless here, because scientists tend to use the word in peculiar ways. Rather than starting with a formal definition, then, I have remembered Wittgenstein’s advice -- that "the meaning of a word is its use in the language" -- and I spend the first chapter of the book discussing mathematical or scientific proofs, or theories or experiments, that are generally regarded as elegant, sometimes contrasting them with those that are not. I begin with mathematical examples since it is mathematicians that get most enthusiastic about elegance, and there are some very pretty examples that are easily accessible to non-mathematicians. I then proceed to the physical and biological sciences, ending the chapter with a description of the experiment, published by William Harvey in 1628, proving -- what was then not known -- that the blood in our bodies circulates; an experiment that required only a bandage and that could have been done at any time in the past.

Looking at the overall picture it becomes clear that elegant proofs or theories or experiments possess most or all of the following features: they are simple, ingenious, concise and persuasive; they often have an unexpected quality, and they are very satisfying. What is more, once one has understood the argument behind the proof or theory or experiment, it can be seen at a glance, and one has no doubts about its validity. Perhaps the most surprising member in this list of features is the "unexpected quality"; so let me give an example. When Thomas Henry Huxley read Darwin’s account of his theory of evolution by natural selection his comment was "How extremely stupid not to have thought of that!"

Q: Is there a particular scientist who best exemplifies this concept?

A: There are many scientists in many fields who could reasonably be suggested, but if there has to be a beauty contest I think the winner would have to be Newton. It’s not just the simple elegance and staggeringly wide-ranging explanatory power of his law of universal gravitation and his three laws of motion, but also the extraordinary breadth of his activities. These ranged from the elegant and highly sophisticated -- the invention of fluxions (the basis of calculus) and his work on optics (including sorting out the nature of white light) -- to the elegant but charmingly simple: measuring the speed of sound by going into the cloister on the north side of Nevile’s Court, Trinity College, seeing with what frequency he had to clap his hands for each clap to coincide with the echo of the previous clap, pacing out the length of the cloister, doing a simple sum and getting the right answer.

Q: How did you become interested in the idea of scientific elegance, and why did you decide to write a book about it?

A: More than twenty years ago I was asked by an undergraduate science society in Cambridge to give a talk about my own research. My colleagues and I in the Cambridge Physiological Laboratory had, as it happens, just got some very interesting experimental results, but we weren’t yet sure that those results were right or that our interpretation of them was valid. To talk about work that might later be proved wrong would be rash; on the other hand to talk about our older experiments when we were preoccupied with thinking about our newer ones didn’t seem very inviting. In this awkward situation I suggested that instead of talking about my own research I talk about a subject that had fascinated me since my schooldays: the nature and attractiveness of elegance in science. Mathematicians, especially pure mathematicians, are of course well known to get excited about elegance, but though scientists talk less about it, elegant theories and elegant experiments do give great pleasure in a wide variety of fields -- and not only to their originators.Anyway, my suggestion was accepted, the talk was given, and I wondered at that time whether it could usefully give birth to a book. Three years ago I decided that it could, and a few months ago it did.

What I am less clear about is what originally made me interested in scientific elegance. The physics teaching at my school was particularly good, and I think I was impressed at the way Newton’s three simple laws of motion and one simple law of gravity could explain so much about celestial or terrestrial motion. And I was also intrigued at the way concepts of force and distance and mass led to the ideas, first of mechanical work and then of energy. In biology I found it fascinating that four different topics -- geographical distribution of animals, comparative anatomy, embryology, and the study of fossils -- all supported the theory of evolution; and of course the idea of natural selection had all the features that "elegance" implied.

Q: Can you give an example of elegance from your own field, physiology?

A: By 1939 it was clear that information is transmitted along nerve fibers as a stream of identical impulses, each impulse consisting of a transient change in the difference in voltage between the inside and the outside of the nerve fiber. Back in 1872, Ludimar Hermann had pointed out that, at the junction of the portion of the nerve with the altered voltage and the adjacent resting nerve, there would be local electric currents both in the fluid surrounding the fiber and the fluid inside it; and he suggested that these local currents might initiate the change of voltage in the adjacent resting nerve. In this way the impulse would travel along the nerve fiber, each bit of nerve being excited by currents from the previous bit. The idea became known as the "local circuit hypothesis," and in 1938 Alan Hodgkin, a young Cambridge Physiologist working in the USA, was discussing it with an American colleague. The American said he could take it seriously only if Hodgkin could show that altering the conductivity of the fluid bathing the nerve fiber altered the speed at which impulses traveled along the fiber.

Using single giant nerve fibers from the squid, Hodgkin showed that replacing the saline bathing fluid with oil or air did indeed slow transmission of impulses along the nerve. That was encouraging, but it might have been the result of deterioration of the nerve in an abnormal environment. He then did an experiment that was as decisive as it was simple. He laid the squid nerve fiber across a row of platinum strips in a damp atmosphere. The tips of the strips ended just above a small trough of mercury, so that raising the trough provided an electrical connection between the strips. He found that raising the trough did increase the speed of transmission of the impulses, and, what is more, the effect was instantaneous. Since nothing in the immediate neighborhood of the nerve was changed, the only possible explanation was that a flow of electric current was involved. The local circuit hypothesis was right.

Q: What is the importance of elegance in science? Should scientists strive for elegance in their work, or is it only ever a happy accident?

A: It certainly isn’t "only ever a happy accident" since there are too many scientists -- Faraday would be a good example -- whose life would have to be regarded as a constant stream of happy accidents. As to "striving," I suspect that in deciding on a research program "elegance" would not normally be a major factor. The importance of "elegance in science" is, first, that it is a source of pleasure, both to the scientist and to those made aware of the elegant work. But partly because it is a source of pleasure, and partly because of the simplicity, ingenuity, conciseness, persuasiveness, unexpectedness, and satisfying quality that the accolade of elegance implies, it makes the work easier to understand, and more memorable. And this is true even when, as sometimes happens, the theory turns out to be wrong. The "comma-free code" discussed in the book’s epilogue is a splendid example.

Q: The book includes examples from a variety of mathematical and scientific disciplines, but you make it clear that you don’t expect readers to have a strong background in any of them. For what audience is the book intended -- and what do you hope they’ll get from it?

A: The book is intended for anyone with a general interest in science, but it is particularly aimed at practicing scientists and those engaged in teaching or in studying science at schools or universities. I believe that too much science teaching is almost wholly impersonal, and that discussion of the way critical problems were solved by the elegant theories or experiments of particular scientists working against particular historical backgrounds can make both learning and teaching much more attractive. In writing the book I have been surprised at what complicated and diverse lives, and what complicated and diverse characters -- at times admirable, at times deplorable -- successful scientists have had, and how closely interwoven their daily lives and their scientific work have sometimes been. To learn about heat without hearing about the extraordinary life of the American farm boy who became Count Rumford, or to learn about light without hearing about the Quaker Thomas Young, seem to me a bit like learning about genetics without knowing about Mendel and his peas.