My father once told me of an emaciated fellow inmate in the Buchenwald concentration camp who had been educated in mathematics. You can tell something about people from what comes to mind when they hear the term “pi.” To the “mathematician” it was the ratio of the circumference of a circle to its diameter. Had I asked my father, who had but a seventh-grade education, he would have said it was a circle of crust filled with apples. One day, despite that gulf between them, the mathematician inmate gave my father a math puzzle to solve. My father thought about it for a few days but could not master it. When he saw the inmate again, he asked him for the solution. The man wouldn’t say, telling my father he must discover it for himself. Sometime later, my father again spoke to the man, but the man held on to his secret as if it were a hunk of gold. My father tried to ignore his curiosity, but he couldn’t. Amid the stench and death around him, he became obsessed with knowing the answer. Eventually the other inmate offered my father a deal—he would reveal the puzzle’s solution if my father would hand over his crust of bread. I don’t know what my father weighed at the time, but when the American forces liberated him, he weighed eighty-five pounds. Still, my father’s need to know was so powerful that he parted with his bread in exchange for the answer.
I was in my late teens when my father recounted that episode, and it made a huge impact on me. My father’s family was gone, his possessions confiscated, his body starved, withered, and beaten. The Nazis had stripped him of everything palpable, yet his drive to think and reason and know survived. He was imprisoned, but his mind was free to roam, and it did. I realized then that the search for knowledge is the most human of all our desires, and that, different as our circumstances were, my own passion for understanding the world was driven by the same instinct as my father’s.
As I went on to study science in college and after, my father would question me not so much about the technicalities of what I was learning, but about the underlying meaning—where the theories came from, why I felt they were beautiful, and what they said about us as human beings. This book, written decades later, is my attempt, finally, to answer those questions.
A few million years ago, we humans began to stand upright, altering our muscles and skeletons so that we could walk in an erect posture, which freed our hands to probe and manipulate the objects around us and extended the range of our gaze so that we could explore the far distance. But as we raised our stance, so too did our minds rise above those of other animals, allowing us to explore the world not just through eyesight but with our thoughts. We stand upright, but above all, we are thinkers.
The nobility of the human race lies in our drive to know, and our uniqueness as a species is reflected in the success we’ve achieved, after millennia of effort, in deciphering the puzzle that is nature. An ancient, given a microwave oven to heat his auroch meat, might have theorized that inside it was an army of hardworking, pea-size gods who built miniature bonfires under the food, then miraculously disappeared when the door was opened. But just as miraculous is the truth—that a handful of simple and inviolable abstract laws account for everything in our universe, from the workings of that microwave to the natural wonders of the world around us.
As our understanding of the natural world evolved, we progressed from perceiving the tides as being governed by a goddess to understanding them as the result of the gravitational pull of the moon, and we graduated from thinking of the stars as gods floating in the heavens to identifying them as nuclear furnaces that send photons our way. Today we understand the inner workings of our sun, a hundred million miles away, and the structure of an atom more than a billion times smaller than ourselves. That we have been able to decode these and other natural phenomena is not just a marvel. It also makes a gripping tale, and an epic one.
Some time ago, I spent a season on the writing staff of the television series Star Trek: The Next Generation. At my first story meeting there, at a table populated by all the show’s other writers and producers, I pitched an idea for an episode that excited me because it involved the real astrophysics of solar wind. All eyes were focused on me, the new guy, the physicist in their midst, as I enthusiastically detailed my idea, and the science behind it. When I was done—the pitch had taken less than a minute—I looked with great pride and satisfaction at my boss, a gruff, middle-aged producer who had once been an NYPD homicide detective. He stared at me for a moment, his face strangely unreadable, and then he said with great force, “Shut up, you f—king egghead!”
When I got over my embarrassment, I realized that what he was so succinctly telling me was that they had hired me for my storytelling abilities, not to conduct an extension school class on the physics of stars. His point was well taken, and I have let it guide my writing ever since. (His other memorable suggestion: if you ever sense that you are going to be fired, turn down the heat on your swimming pool.)
In the wrong hands, science can be famously boring. But the story of what we know and how we know it isn’t boring at all. It is supremely exciting. Full of episodes of discovery that are no less compelling than a Star Trek episode or our first trip to the moon, it is peopled by characters as passionate and quirky as those we know from art and music and literature, seekers whose insatiable curiosity took our species from its origins on the African savanna to the society we live in today.
How did they do that? How did we go from a species that had barely learned to walk upright and lived off whatever nuts and berries and roots we could harvest with our bare hands to one that flies airplanes, sends messages instantly around the globe, and re-creates in enormous laboratories the conditions of the early universe? That is the story I want to tell, for to know it is to understand your heritage as a human being.
It has become a cliché to say that today the world is flat. But if the distances and differences between countries are effectively diminishing, the differences between today and tomorrow are growing. When the first cities were built, around 4000 B.C., the fastest way to travel long distances was by camel caravan, which averaged just a few miles per hour. Somewhere between a thousand and two thousand years later, the chariot was invented, raising the maximum speed to about 20 miles per hour. Not until the nineteenth century did the steam locomotive finally allow faster travel, reaching speeds up to 100 miles per hour by the century’s end. But although it took humans two million years to graduate from running at 10 miles per hour to racing across the country at 100 miles per hour, it took only fifty years to achieve the next factor of ten, with the creation of an airplane that could fly 1,000 miles an hour. And by the 1980s, humans were traveling at more than 17,000 miles per hour in the space shuttle.
The evolution of other technologies exhibits a similar acceleration. Take communications. As late as the nineteenth century, the Reuters news service was still using carrier pigeons to fly stock prices between cities. Then, by the mid-nineteenth century, the telegraph had become widely available, and in the twentieth century, the telephone. But while it took eighty-one years for the landline telephone to achieve a market penetration of 75 percent, the cell phone achieved that in twenty-eight years, and the smartphone in thirteen. In recent years, first email, and then texting, largely supplanted phone calls as a tool for communication, while the phone is increasingly employed not for phone calls but as a pocket computer.
“The world of today,” said economist Kenneth Boulding, “is as different from the world in which I was born as that world was from Julius Caesar’s.” Boulding was born in 1910 and died in 1993. The changes he witnessed—and many others that have occurred since—were the products of science, and the technology it spawns. Such changes are a greater part of human life than ever before, and our success at work and in society is increasingly predicated on our ability to both assimilate innovation and to create innovations ourselves. For today, even those of us who don’t work in science or technology face challenges that require us to innovate if we are to remain competitive. And so the nature of discovery is an important topic for us all.
To gain perspective on where we are today, and to have a hope of understanding where we are going, one must know where we came from. The greatest triumphs of human intellectual history—writing and mathematics, natural philosophy, and the various sciences—are usually presented in isolation, as if each had nothing to do with the others. But that approach emphasizes the trees and not the forest. It neglects, by its very nature, the unity of human knowledge. The development of modern science, for example—often heralded as the work of “isolated geniuses” such as Galileo and Newton—did not spring from a social or cultural vacuum. It had its roots in the approach to knowledge invented by the ancient Greeks; it grew from the big questions posed by religion; it developed hand in hand with a new approach to art; it was colored by the lessons of alchemy; and it would have been impossible without social progress ranging from the grand development of the great universities of Europe to mundane inventions such as that of the postal systems that grew to connect nearby cities and countries. The Greek enlightenment, similarly, sprouted from the astounding intellectual inventions of earlier peoples in lands such as Mesopotamia and Egypt.
As a result of such influences and connections, the account of how humans came to understand the cosmos does not consist of isolated vignettes. It forms, like the best fiction, a coherent narrative, a unified whole whose parts have numerous interconnections, and which begins at the dawn of humanity. In what follows, I offer a selective, guided tour of that odyssey of discovery.
Our tour begins with the development of the modern human mind and features the critical eras and turning points at which that mind leapt to new ways of looking at the world. Along the way, I will also portray some of the fascinating characters whose unique personal qualities and modes of thought played an important role in those innovations.
Like many tales, this is a drama in three parts. Part I, spanning millions of years, traces the evolution of the human brain and its propensity to ask “Why?” Our why’s propelled us to our earliest spiritual inquiries and led, eventually, to the development of writing and mathematics and the very concept of laws—the necessary tools of science. Ultimately those whys led to the invention of philosophy, the insight that the material world operates according to rhyme and reason that can, in principle, be understood.
The next phase of our journey explores the birth of the hard sciences. It is a story of revolutionaries who had the gift of seeing the world differently, and the patience, grit, brilliance, and courage to continue striving through all the years and even decades it sometimes took to develop their ideas. These pioneers—thinkers such as Galileo, Newton, Lavoisier, and Darwin—fought long and hard against the established doctrine of their day, so their stories are inevitably tales of personal struggle, sometimes with stakes as high as life itself.
Finally, as in many good stories, our tale takes an unexpected turn just when its heroes have reason to think they’re close to the end of their journey. For no sooner did humanity come to believe it had deciphered all the laws of nature than, in a strange twist of the plot, such thinkers as Einstein, Bohr, and Heisenberg discovered a new realm of existence, an invisible one, in which those laws had to be rewritten. That “other” world—with its otherworldly laws—plays out on a scale too small to be apprehended directly: the microcosmos of the atom, ruled by the laws of quantum physics. It is those laws that are responsible for the enormous and still accelerating changes that we are experiencing in society today, for it is our understanding of the quantum that enabled the invention of computers, cell phones, televisions, lasers, the Internet, medical imaging, genetic mapping, and most of the new technologies that have revolutionized modern life.
While Part I of the book covers millions of years, and Part II covers hundreds, Part III spans mere decades, reflecting the exponential acceleration in the accumulation of human knowledge—and the newness of our forays into this strange new world.
The odyssey of human discovery stretches over many eras, but the themes of our quest to understand the world never vary, as they arise from our own human nature. One theme is familiar to anyone who works in a field dedicated to innovation and discovery: the difficulty in conceiving of a world, or an idea, that is any different from the world or ideas that we already know.
In the 1950s, Isaac Asimov, one of the greatest and most creative science fiction writers of all time, wrote the Foundation trilogy, a series of novels set many thousands of years in the future. In those books, the men commute to work in offices every day, and the women stay home. Within only a few decades, that vision of the distant future was already a thing of the past. I bring this up because it illustrates an almost universal limitation of human thought: our creativity is constrained by conventional thinking that arises from beliefs we can’t shake, or never even think of questioning.
The flip side of the difficulty of conceiving change is the difficulty of accepting it, and that is another recurring theme of our story. We human beings can find change overwhelming. Change makes demands on our minds, takes us beyond our comfort zones, shatters our mental habits. It produces confusion and disorientation. It requires that we let go of old ways of thinking, and the letting go is not our choice but is imposed upon us. What’s more, the changes resulting from scientific progress often upend belief systems to which large numbers of people—and possibly their careers and their livelihoods—are attached. As a result, new ideas in science are often met with resistance, anger, and ridicule.
Science is the soul of modern technology, the root of modern civilization. It underpins many of the political, religious, and ethical issues of our day, and the ideas that underlie it are transforming society at an ever faster pace. But just as science plays a key role in shaping the patterns of human thought, it is also true that the patterns of human thinking have played a key role in shaping our theories of science. For science is, as Einstein remarked, “as subjective and psychologically conditioned as any other branch of human endeavor.” This book is an effort to describe the development of science in that spirit—as an intellectual as well as a culturally determined enterprise, whose ideas can best be understood by an examination of the personal, psychological, historical, and social situations that molded them. To look at science that way sheds light not just on the enterprise itself, but on the nature of creativity and innovation, and, more broadly, on the human condition.