Freedom in Nature
In his 1939 memoir Wind, Sand and Stars, the beloved French aristocrat, aviator, and writer Antoine de Saint-Exupéry examines the phenomenon of life through the lens of his experiences as an airmail carrier for Aéropostale. In the third chapter of the book, which is entitled “The Tool,” the author expresses his admiration for the modern aircraft, marveling at its simple elegance and its evolution over time. “It is as if there were a natural law which ordered that to achieve this end, to refine the curve of a piece of furniture, or a ship’s keel, or the fuselage of an airplane, until it gradually partakes of the elementary purity of the curve of a human breast or shoulder, there must be the experimentation of several generations of craftsmen.” He compares the aircraft’s engineers to waves, slowly wearing down and smoothing the surfaces of pebbles. “A designer knows he has achieved perfection not when there is nothing left to add,” Saint-Exupéry explains, “but when there is nothing left to take away.”
Although Saint-Exupéry is best remembered for his lyrical, ethereal literary contributions in Wind, Sand and Stars,s and the children’s novella The Little Prince, “The Tool” demonstrates a profound insight into mechanical engineering, technological evolution, and, indeed, the scientific process itself. In science, and especially in physics, there is a certain fascination with the portrayal of nature in simpler and simpler terms, exemplified by the repeated attempts to refine the natural world over time into a single unifying observation. As Saint-Exupéry’s countryman, the physicist, mathematician, and philosopher of science Henri Poincaré once wrote, “the true and only goal of science is to reveal unity rather than mechanism.”
Poincaré’s insightful quotation is reproduced in the final chapter of The Physics of Life, the latest popular contribution from Adrian Bejan, renowned scholar, physicist, and professor of mechanical engineering at the Duke University Pratt School of Engineering. Bejan, who boasts 18 honorary degrees, 28 books, and over 600 scholarly articles, is most recognized within academia for his discovery of the constructal law of thermodynamics in 1996. “For a finite-size system to persist in time (to live),” the law states, “it must evolve in such a way that it provides easier access to the imposed currents that flow through it.” Outside of the ivory tower, Bejan is best known for Design in Nature (2012), a book which introduced lay audiences to the constructal law through examples of evolutionary flow systems including river basins, lightning strikes, and the Hartsfield-Jackson Atlanta International Airport. Now, in The Physics of Life, the author re-applies his law to reveal to the average reader the simple unity between things as seemingly unrelated as arteries, athletes, and Saint-Exupéry’s beloved airplanes; balancing his analysis between common sense and complex thermodynamics, he incorporates them all en route to a radical re-imagining of the phenomenon of life itself.
After an introductory chapter or two, Bejan opens his analysis in The Physics of Life with a discussion of fire and heat flow. The early, open fires of our nomadic ancestors provided mankind with obvious advantages, he explains, but they also left much to be desired. As flow systems, open fires wastefully dissipate most of their energy to the environment around them, and are inferior to modern, flow-based designs such as central heating, which seek to channel the dissipated energy directly through a living space itself rather than aimlessly into the surroundings. Of course, the same principle can be scaled up and applied to the distribution of heat energy across the population as well. “In order to burn less fuel on a populated landscape,” the author goes on to explain, “the burning of fuel must be allocated to areas in such a way that more and more of the heat that ‘rains’ on the area is forced to fall on the homes, not between the homes.” Thus is the concept of hierarchy introduced, and from there Bejan draws nearly innumerable analogies. Our organs are alive with the same kinds of currents, and the larger organs demand larger currents. Those organs motivate our bodies, and those of us with bigger bodies can harness more fuel and energy to move faster and farther. The degree of an animal’s muscle mass, heat mass, and lung mass is proportional to its overall body mass, and this relationship is mathematically identical to that between the mass of an engine and the mass of whatever vehicle it serves. The larger a vehicle, the more efficient it is as an overall means of travel, which is why airplanes, like athletes, have continued to become bigger over time. (It seems that Antoine de Saint-Exupéry, with his analogies between aircraft and biological evolution, may have been onto something after all.)
In the same way that popular works like Freakonomics, Predictably Irrational, and Black Swan offer their readers exciting, alternative frameworks for understanding common phenomena, these sections of The Physics of Life empowers the audience to re-interpret the form of the physical world through the simple perspective of flow. The result is that the reader’s surroundings—the trees, the traffic, and the tributaries which formerly flowed by without notice—all of a sudden cease to idle beyond perception, and leap instead from the scenery anew, objects of observation no longer inert, environmental tchotchkes transformed to occasions for contemplation.
That being said, however, The Physics of Life most impresses when Bejan moves beyond the confines of purely physical systems of flow and opens his analysis to more abstract patterns of movement such as wealth, politics, science, and knowledge. Such processes, according to Bejan, are as literally alive as the physical entities of earlier chapters, and the author applies his ideas to them in order to answer another collection of disparate questions. Why is it the case that successful politicians so often reverse their views on key controversial issues? What promotes outsourcing and globalization, and is it true that these phenomena are just hands to be played in a zero-sum game of profit and loss? Are businesses engines or leeches of economic growth? In passing, the author occasionally uses the Occupy Wall Street movement as a synecdoche for certain viewpoints while he entertains possible answers to these questions. Although he never criticizes the movement or its constituents directly, he can’t resist subjecting even Occupy Wall Street to its own flow analysis in order to demonstrate why it received less sympathy from the residents of New York—who live in a city with an easily clogged two-dimensional vasculature—than Occupy Central did from the residents of the flow-friendlier, more three-dimensional Hong Kong.
Bejan is both fair and diplomatic when he discusses these issues but the answers he offers are definitive, and he comes down firmly on the side of the free economy. “Capitalism happens,” the author explains, in what is perhaps the pithiest summary of spontaneous order that has ever been committed to paper. The free market economy is itself a living system, an avenue for flow which, when allowed to run its course, provides us all with easier and easier access to the resources that rush through it. “It is a natural phenomenon,” Bejan writes, “and it is good like all natural phenomena to which humans have attached themselves, from fire to domesticated animals, to the use of money, air travel and electric power.” By locating capitalism within the realm of the natural world in this way, Bejan incorporates it into his redefinition of “life.” It stands to reason from there that systems such as socialism and communism, which would seek to impede this natural flow of life, represent an unnatural form of stasis that is associated with death. It goes almost without saying that libertarian-minded readers will find a lot to like in this author’s analysis of the social, political, and economic elements of life.
In truth, though, The Physics of Life is as much about the eponymous phenomenon as it is about its author’s own life. Before he became a physicist, Bejan from a young age found success in a variety of diverse and even seemingly unrelated endeavors. As a child in communist Romania, Bejan’s artistic talents earned him special academic consideration, as did his strength in mathematics. Adrian Bejan was more, however, than just an artist and an academic; he was an accomplished athlete too, and in his early adult years he became a member of the national basketball team. The book is peppered with the details of its author’s upbringing, from his impressive accomplishments to his formative experiences under a regime of oppressive communism. In reviewing the totality of his work in The Physics of Life, then, it is easy to spot those early seeds from which Bejan’s ideas have sprung, and to trace his life’s work from the basketball courts of Romania to the classrooms at MIT, Berkeley, and Duke.
Indeed, if there is a fault to be found with The Physics of Life, it is that perhaps no one can truly appreciate the totality of the work as much as the author himself. Adrian Bejan is an artist and an athlete, a scholar, a scientist, and a professor, and he understands all of these elements of himself through his expertise in physics. The book’s target audience may contain individuals with intimate knowledge of one, two, or even three of these subjects, but few will feel fully at home with all of the different topics of discussion. Is there a reader for this book as familiar with both the theories of physics and the elegant philosophy of basketball as the writer himself, one who is totally capable of fathoming and appreciating the true extent of the connections between the two?I suspect Bejan would reject the question itself. Although it is true that a book such as this one would require a parade of narrow experts to suss out the similarities between a bunch of the different aspects of life, The Physics of Lifeis not really about similarities. Far from similar, it argues, all of these things—from our bodies to our economies back to Saint-Exupéry’s airplanes—are actually one and the same. If you truly understand one facet of life, then, you must truly understand them all. All of these things are equal. “All this,” the author argues, “is life.”
Chris Bassil is a medical student and scientific researcher who currently lives in North Carolina.