Brockman, John (ed.), This Explains Everything: Deep, Beautiful, and Elegant Theories of How the World Works, Harper Perennial, 2013.
In 1997, the Reality Club, which was formed in 1981 to explore themes of the post-Industrial Age, went on-line and was rebranded as “Edge.” Those involved with Edge brainstorm to ask an annual question and challenge brilliant people to answer it. The 2012 question, “What is your favorite deep, elegant, or beautiful explanation?” which sought to gather people’s opinions about their favorite scientific theory or explanation, led to more than 200 answers. This book includes edited forms of 148 of those answers it its 411 pages, making the average chapter less than 3 pages long. A common theme in the published answers is the proposal of “a simple and non-obvious idea … as the explanation for a diverse and complicated set of phenomena.”
Not surprisingly, Darwin’s theory of evolution via natural selection is mentioned many times, either as the main topic of an essay or as the author’s first choice that s/he passed over in favor of another explanation (because so many, perhaps more qualified, others will likely address evolution). It is pointed out in the very first chapter, by psychologist Susan Blackmore, that natural selection explains everything, not just life; it has been used to explain transformations in languages, the banking system, the Chelsea soccer team, and iPhone.
I enjoyed reading this book immensely and spent more time on it, per page, than on any other book. Each of the 148 bite-size chapters is a delight, and trying to summarize the content would lead to a book-length review. So, I have chosen to provide the titles of some of the chapters I found more enlightening, and either quote from or write a few words about each. As chapters are not numbered in this book, I begin each description with the chapter’s starting page number.
[p. 5] “Redundancy Reduction and Pattern Recognition,” by Richard Dawkins: The world around us does not change much from one instant to the next. Thus, our sensory system achieves economy by signaling change, rather than the actual state it detects at a given time. For example, neurons signaling temperature do not fire more rapidly when they detect high temperature; rather, their firing rate increases when there is a change in temperature, dying away to a low, resting frequency when the change subsides.
[p. 9] “The Power of Absurdity,” by Scott Atran: “Humankind’s strongest social bonds, including capacities for cooperation and forgiveness, and for killing and allowing oneself to be killed, are born of commitment to causes and courses of action that are ‘ineffable’—that is, fundamentally immune to logical assessment for consistency and to empirical evaluation for costs and consequences. The more materially inexplicable one’s devotion and commitment to a sacred cause—that is, the more absurd—the greater the trust others place in it and the more that trust generates commitment on their part.”
[p. 11] “How Apparent Finality Can Emerge,” by Carlo Rovelli: According to Darwin, spectacularly simple mechanisms produce phenomena that appear to be governed by final causes (e.g., we may think that we have mouths “so” we can eat). Such apparent false final causes exist wherever there is life, because we only observe those phenomena that have survived through reproduction.
[p. 15] “The Overdue Demise of Monogamy,” by Aubrey de Grey: Monogamy can be explained quite well from an evolutionary perspective. But we may be on the verge of a significant change. In a world which is no longer driven by reproductive efficiency, sex assumes a status similar to many other recreational activities.
[p. 22] “The Dark Matter of the Mind,” By Joel Gold: “The universe consists primarily of dark matter. We can’t see it, but it has an enormous gravitational force. The conscious mind—much like the visible aspect of the universe—is only a small fraction of the mental world. The dark matter of the mind, the unconscious, has the greatest psychic gravity. Disregard the dark matter of the universe and anomalies appear. Ignore the dark matter of the mind and our irrationality is inexplicable.”
[p. 25] “An Unresolved (and Therefore Unbeautiful) Reaction to the Edge Question,” by Rebecca Newberger Goldstein: What makes us think that beauty and rigor have anything to do with each other? “Is there anything to this notion of explanatory beauty, a guide to choosing between explanatory alternatives, or is it just that any explanation that’s satisfactory will, for that very reason and no other, strike us as beautiful, beautifully explanatory, so that the reference to beauty is, once again, without any substance?”
[p. 39] “Simplicity Itself,” by Thomas Metzinger: Albert Einstein’s view, that simplicity is the ultimate goal of a scientific explanation, is often quoted. “Can the fundamental insight—the destructive, creative virtue of simplicity—be transposed from the realm of science onto culture or onto the level of conscious experience? What kind of formal simplicity would make our culture a deeper, more beautiful culture? And what is an elegant mind?”
[p. 42] “Evolutionary Genetics and the Conflicts of Human Social Life,” by Steven Pinker: In a succinct, 4-page statement of the human condition, the author elaborates on the following views in bullet-point form. (a) Conflict is part of the human condition. (b) The main refuge from this conflict is the family. (c) Even families are not perfect havens from conflict. (d) Sex is not entirely a pastime of mutual pleasure between consenting adults. (e) Love is not all you need, and does not make the world go round.
[p. 50] “Group Polarization,” by David G. Myers: The elegant explanation in this essay is that “group interaction tends to amplify people’s initial inclinations.” The Internet allows like-minded individuals, from conspiracy schemers to neo-Nazis, to find and influence one another. Put in the form of an equation: “opinion-segregation + conversation –> polarization.”
[p. 55] “Unconscious Inferences,” by Gerd Gigerenzer: A sensation in itself does not carry information. Rather, it is the brain that draws unconscious inferences about the meaning of a sensation. Take the following image, for example, where the right half is the same as the left half, turned upside down. Turn the entire image upside-down and your perception changes. Our unconscious inferences are based on evidence or assumptions (in this case, that a shade on the upper part of a dot is nearly always associated with a concave shape) that are usually reliable but can mislead us in some circumstances. (Image: source)
[p. 65] “Why is Our World Comprehensible?” by Andrei Linde: In the words of Albert Einstein, “The most incomprehensible thing about the world is that it is comprehensible.”
[p. 71] “Our Universe Grew Like a Baby,” by Max Tegmark: Right after conception, the number of cells in a baby doubles every day, going from 1 to 2, to 4, and so on. Fortunately for mothers, the doubling does not continue all the way to the end of the pregnancy. According to the inflation theory of Alan Guth and others, this is exactly what happened to the universe at Big Bang, except that the doubling did not happen daily but almost instantaneously.
[p. 79] “Impossible Inexactness,” by Satyajit Das: “There was a world before Heisenberg and his uncertainty principle. There is a world after Heisenberg. They are the same world, but they are different.”
[p. 82] “The Next Level of Fundamental Matter,” by Haim Hariri: “The twelve fundamental quarks and leptons and their antiparticles all have electric charges 0, 1/3, 2/3, and 1 or the negative values of the same numbers. … Why are all the charges multiples of 1/3 of the electron charge …? Why are quark charges and lepton charges related to each other by simple ratios?”
[p. 103] “Commitment,” by Richard H. Thaler: Economics theory suggests that we are always better off when we have more choices. However, there are many examples where restricting future choices and committing to specific courses of action might be beneficial. “Many of society’s thorniest problems, from climate change to Middle East conflict, could be solved if the relevant parties could only find a way to commit themselves to some future course of action.”
[p. 106] “True or False: Beauty is Truth,” Judith Rich Harris: “The theory of the modular mind is not beautiful or elegant. But not being a poet, I prize truth above beauty.”
[p. 119] “Why the Human Mind May Seem to Have an Elegant Explanation Even If It Doesn’t,” by Nicholas Humphrey: Consider the example sequence 2, 4, 6, 8, which seems to follow the simple rule x + 2 in forming the next term from a given term x but can also be explained by the more complicated rule –(x^3)/44 + 3x^2/11 + 34/11. The author notes that most people find the first explanation simpler and more elegant and that the human mind automatically gravitates toward that simpler explanation. But if further observation reveals that the next term in the sequence is 8.91 rather than 10, then the second (correct, but more complex) explanation becomes more elegant. “How often does the real world tease us by seeming simpler than it really is?”
[p. 125] “On Oceans and Airport Security,” by Kevin P. Hand: “So the next time you’re in airport security and frustrated by that disorganized person in front of you who can’t seem to get it through his head that his belt, wallet, and watch will all set off the alarm, just take a deep breath and think of the possibly habitable distant oceans [e.g., on Europa, one of Jupiter’s moons] we now know of, thanks to the same beautiful physics that’s driving you nuts as you contemplate missing your plane.”
[p. 129] “Why Some Sea Turtles Migrate,” by Daniel C. Dennett: Plate tectonics explains why some turtles cross the Atlantic to lay eggs on the shores of South America, after mating on the west coast of Africa. Their swim was quite short millions of years ago. Each year, the swim became an inch or so longer, which was hardly noticeable. “Eventually they were crossing the ocean to lay their eggs, having no idea, of course, why they would do such an extravagant thing.”
[p. 139] “Subjective Environment,” by Andrian Kreye: The perception of an organism from its environment is quite subjective and thus changes from one kind of organism to another or among different organisms of the same kind. “Ticks perceive their surroundings by the directions of up and down, by warm and cold, or by the presence or absence of butyric acid. Their actions to survive and procreate are crawling, waiting, and gripping.” Based on these observations, Jakob von Uexkull deduced that any organism’s perception of space and time are subjective.
[p. 152] “All We Need Is Help,” by Seirian Sumner: Efficiencies resulting from division of labor explain not only the development of human and animal societies but also the emergence of complex, multicell organisms. Specialized cells that cooperate give an organism survival advantage over its single-cell counterparts.
[p. 179] “Epigenetics—The Missing Link,” by Helen Fisher: Genes turning on and off due to environmental factors provide a beautiful explanation for variability in otherwise identical members of a species. “Take the Moroccan Amazighs, or Berbers, people with highly similar genetic profiles who now reside in three different environments: Some roam the deserts as nomads, some farm the mountain slopes, some live in the towns and cities along the Moroccan coast. And depending on where they live, up to one-third of their genes are differentially expressed.”
[p. 193] “Why We Feel Pressed for Time,” by Elizabeth Dunn: Why do modern humans feel more pressed for time than our ancestors? Scarcity and value are conjoined twins. When a resource is scarce, be it diamonds or drinking water, it is perceived as more valuable. As time becomes worth more and more money due to technological progress, our minds automatically perceive it as a scarcer commodity. “If feelings of time-scarcity stem in part from a sense that time is highly valuable, then one of the best things we can do to reduce this sense of pressure may be to give our time away.”
[p. 221] “The Pigeonhole Principle,” by Jon Kleinberg: If a flock of pigeons lands in a group of trees and there are more pigeons than trees, then at least one tree will contain more than one pigeon. Surely such an obvious statement can’t lead to any deep discoveries! Yet it does. Consider this less obvious statement: Your family tree must have a loop, in the sense that sometime in the past 4000 years there was a person in your family tree whose father and mother were descendants of the same person. This is a direct result of the fact that in 40 generations, which is way less than 4000 years, a family tree with no loop must include more than 2^40 individuals, given that each person has two parents. Scientific studies have shown that in the same 4000-year period, at most a trillion (10^12) people have lived on earth. Because 2^40 > 10^12, your family tree cannot be loop-free.
[p. 252] “Evolutionarily Stable Strategies,” by S. Abbas Raza: Why do common animal species all have nearly equal numbers of males and females? Even among walruses, most of whose males die virgins and a few males monopolize most of the females, the 50-50 ratio exists. Don’t the reproductively useless male walruses consume resources, making it evolutionarily advantageous to have fewer males to begin with? The answer is that an unbalanced ratio, such as 30-70 would not be stable, but the mathematical argument, though easily understood, is rather long.
[p. 255] “The Collingridge Dilemma,” by Evgeny Morozov: “When change is easy, the need for it cannot be foreseen; when the need for change is apparent, change has become expensive, difficult, and time-consuming.” This dilemma is an elegant way to explain many of our complex ethical and technological quandaries.
[p. 263] “Subverting Biology,” by Patrick Bateson: Inbreeding is generally seen as undesirable, but in recent years, the debate has become much more nuanced. A study of a human Icelandic population has confirmed previous animal studies that there is an optimal degree of relatedness in terms of improving survival chances. In the study, couples who are third or fourth cousins have, on average, a larger number of grandchildren than more closely or more distantly related partners.
[p. 269] “Why Do Movies Move?” by Alvy Ray Smith: A photo taken from a fast-moving object appears blurred, which helps us perceive the speed and direction of movement. If in a movie that runs at 24 frames per second, say, each frame is a perfectly focused image, the movie appears jumpy to the human eye. The reason computer games have achieved remarkable realism is that we have learned how to blur images artificially, and we possess the computational power to enable this artificial blurring to be done in real time.
[p. 273] “Would You Like Blue Cheese with It?” Albert-Laszlo Barabasi: The science of large-scale or complex networks can be applied to improving culinary creations. If we graph popular dishes with respect to the ingredients they contain, we notice that certain ingredients are paired together much more often than we should expect based on their individual popularity. Tomato and garlic, combined in 12% of all recipes, fall in this category. The frequency will of course vary in different regions of the world, but a complete analysis of such trends provides valuable clues for creating new dishes or assessing their potential appeal.
[p. 287] “One Coincidence; Two Deja Vus,” by Douglas Coupland: Human beings, regardless of their ages and cultural backgrounds, experience about one coincidence and 2 deja vus per year.
[p. 299] “Natural Selection is Simple but the Systems It Shapes Are Unimaginably Complex,” by Randolph Nesse: “Trying to reverse-engineer brain systems focuses important attention on functional significance, but it is inherently limited, because brain systems were never engineered in the first place.”
[p. 305] “Out of the Mouths of Babes,” by Nicholas A. Christakis: “Why is the sky blue?” This question is asked by children and distinguished scientists alike. Here is an explanation that evaded the brightest scientific minds for centuries. When the light’s wavelength is on the same order as the size of the gas molecules, the intensity of scattered light varies inversely with the 4th power of its wavelength. Blue and violet, having shorter wavelengths, are scattered more than the other colors. “It’s as if all the molecules in the air preferentially glowed blue, which is what we then see everywhere around us.”
[p. 315] “The Precession of the Simulacra,” by Douglas Rushkoff: There’s the land and there is the maps and lines we use to represent the land. We then fight wars over where to draw the lines. There are real companies, stocks that represent their worth, and bets on the stocks that make or lose money depending on how stock prices move. Then there are credit default swaps that insure against losses. At this point, we are extremely disconnected from reality. “And that is when we become particularly vulnerable to illusion, abuse, and fantasy. Because once we are living in a world of created symbols and simulations, whoever has control of the map has control of our reality.
[p. 317] “Time Perspective Theory,” by Philip Zimbardo: People are of three types, and there are various subtypes in each category: those who focus on the past (“good old days” or regrets/trauma), present-oriented individuals (hedonistic “follow my heart” or fatalistic “what’s the use”), and future-minded planners (“here are my goals” or heaven/hell). The Zimbardo Time Perspective Inventory, or ZTPI, correlates scores on these time dimensions with other psychological traits and behavior. The correlation is often very strong, being around 0.70 between future orientation and conscientiousness and 0.75 between past-negative orientation and the traits of anxiety, depression, and anger.
[p. 324] “Implications of Ivan Pavlov’s Great Discovery,” by Stephen M. Kosslyn: Anticipatory salivation, observed in dogs that realize they are about to be fed, based on movement and gesture patterns they have seen just before being fed in the past, explains why we feel relief right after taking pain medication (way before the chemistry of pain relief kicks in).
[p. 328] “Nature is Cleverer than We Are,” by Terrence J. Sejnowski: Temporal Difference (TD) learning provides an excellent method of learning a sequence of decisions leading to a goal. It has been applied to the game of backgammon to allow a computer program to learn from scratch (only the game rules are supplied to the program). The program then plays against itself repeatedly and uses the win/loss outcomes to value particular sequences of moves. It is rather surprising that such a program after only about a million games acquires championship-level skills.
[p. 351] “The Beautiful Law of Unintended Consequences,” by Robert Kurzban: Changing one parameter in a complex system may lead to unintended, though not necessarily unanticipated, consequences. This happens all the time in economic and social systems. For example, the city of Sydney in Australia placed a bounty on rats as a way of dealing with the 1900 plague. The bounty was certainly well-intentioned, but it led to people breeding rats, in order to claim the bounty.