For many years my wife and I have spent our summers on an island in Maine. It’s a small island, only about thirty acres in size, and there are no bridges or ferries connecting it to the mainland. Consequently, each of the six families who live on the island has their own boat. Some of us were not nautical people at first, but over the years we have all learned by necessity. Most challenging are trips to the island at night, when the land masses are only dim shapes in the distance and you must rely on compass headings or faint beacons to avoid crashing into rocks or losing your way. Nevertheless, some of us do attempt the crossing at night.
My story concerns a particular summer night, in the wee hours, when I had just rounded the south end of the island and was carefully motoring toward my dock. No one was out on the water but me. It was a moonless night, and quiet. The only sound I could hear was the soft churning of the engine of my boat. Far from the distracting lights of the mainland, the sky vibrated with stars. Taking a chance, I turned off my running lights, and it got even darker. Then I turned off my engine. I lay down in the boat and looked up. A very dark night sky seen from the ocean is a mystical experience. After a few minutes, my world had dissolved into that star-littered sky. The boat disappeared. My body disappeared. And I found myself falling into infinity. A feeling came over me I’d not experienced before. Perhaps a sensation experienced by the ancients at Font-de-Gaume. I felt an overwhelming connection to the stars, as if I were part of them. And the vast expanse of time—extending from the far distant past long before I was born and then into the far distant future long after I will die—seemed compressed to a dot. I felt connected not only to the stars but to all of nature, and to the entire cosmos. I felt a merging with something far larger than myself, a grand and eternal unity, a hint of something absolute. After a time, I sat up and started the engine again. I had no idea how long I’d been lying there looking up.
I have worked as a physicist for many years, and I have always held a purely scientific view of the world. By that, I mean that the universe is made of material and nothing more, that the universe is governed exclusively by a small number of fundamental forces and laws, and that all composite things in the world, including humans and stars, eventually disintegrate and return to their component parts. Even at the age of twelve or thirteen, I was impressed by the logic and materiality of the world. I built my own laboratory and stocked it with test tubes and petri dishes, Bunsen burners, resistors and capacitors, coils of electrical wire. Among other projects, I began making pendulums by tying a fishing weight to the end of a string. I’d read in Popular Science
or some similar magazine that the time for a pendulum to make a complete swing was proportional to the square root of the length of the string. With the help of a stopwatch and ruler, I verified this wonderful law. Logic and pattern. Cause and effect. As far as I could tell, everything was subject to numerical analysis and quantitative test. I saw no reason to believe in God, or in any other unprovable hypotheses.
Yet after my experience in that boat many years later, I understood what Lord Indra of the Vedas must have felt when he first drank soma and could see the light of the gods. I understood the powerful allure of the Absolutes—ethereal things that are all-encompassing, unchangeable, eternal, sacred. At the same time, and perhaps paradoxically, I remained a scientist. I remained committed to the material world.
. . .
Belief in various Absolutes is alive and well in the world today. A new survey of 35,000 adults by the Pew Research Center found that 89 percent of Americans believe in God, and 74 percent believe in life after death—that is, in some form of immortality. A somewhat older survey by the Barna Group, an organization devoted to religion and culture, found that 50 percent of Christians in America believe in some form of absolute truth, while 25 percent of non-Christians do so. Buddhists worldwide believe in the Four Noble Truths. Hindus worship Brahman, the embodiment of eternal and absolute truth. Belief in certain physical manifestations of the Absolutes is also alive and well. A 2014 Gallup survey found that 42 percent of Americans believe in the constancy of species—in particular, that humans were created in their present form in the first days of the planet.
. . .
In the last couple of centuries and especially in recent decades, many of the Absolutes have been challenged by discoveries in science. Nothing in the physical world seems to be constant or permanent. Stars burn out. Atoms disintegrate. Species evolve. Motion is relative. Even other universes might exist, many without life. Unity has given way to multiplicity. I say that the Absolutes have been challenged rather than disproved, because the notions of the Absolutes cannot be disproved any more than they can be proved. The Absolutes are ideals, entities, beliefs in things that lie beyond the physical world. Some may be true and some false, but the truth or falsity cannot be proven.
. . .
In recent years, I’ve gotten to know a prominent Buddhist monk in Cambodia by the name of Yos Hut Khemacaro. His friends call him Khema. He was born in 1948 in a little farming village in the province of Prey Veng and went to a primary school there administered by monks. At the age of ten, as he now vividly recalls, he was “attracted to learn wisdom” and began studying Buddhism. Eventually he was ordained a monk himself. In 1973, Khema started working with the United Nations on human rights, in Australia and Thailand. After the devastation of the Khmer Rouge genocide in the mid to late 1970s, during which monks were targeted along with all educated people, Khema returned to Cambodia and played a major role in rebuilding the Buddhist monkhood there.
I visited Khema one warm day in January at Wat Lanka, his monastery on a busy avenue in Phnom Penh. I was hoping that he might help me fathom my communion with the stars that summer night in Maine and other experiences I’d not understood. Buddhism embodies an interesting mix of beliefs. The Four Noble Truths would appear to reside within the realm of the Absolutes, while the Buddhist doctrine of impermanence is a Relative.
Wat Lanka is a large temple complex containing several pagodas, patios and walkways, and living quarters for some two hundred monks. The magnificent front gate rises forty feet high and is guarded by stone lions on both sides. As soon as you step through that arched edifice, you leave behind the steady drone of motors and the shouting of street sellers—and enter a realm of serenity. Slowly, I walked past the gold-leaf pagodas. I passed obelisk-like stone stupas and scattered stone pots filled with red and pink bougainvillea. I passed through courtyards with young men in orange robes quietly strolling in pairs. Eventually, I came to Khema’s living quarters, a tiny house at the back end of the complex. We sat under some trees. A faint scent of jasmine wafted through the air.
Under the trees, Khema and I began discussing modern physics and cosmology. I had brought him one of my own books on the subject. “Buddhism is in complete agreement with science,” Khema said slowly and smiled. Then he added, “Science puts in more details.” Khema explained the Buddhist belief that the universe has gone through an infinite number of cycles in the past and will go through an infinite number of cycles in the future. When I mentioned to him that modern cosmologists have evidence that the universe will continue expanding without further cycles, he laughed. Perhaps he thought it was preposterous that science could know such a thing. Or perhaps he thought it delightful that science could know such a thing. While we were talking, Khema’s sister, an ancient nun with a shaved head, appeared from somewhere and silently served us tea. I noticed that her hands were wrinkled and worn, like the cracked yellow paint on the walls of Khema’s house.
I asked Khema how Buddhists know that the universe has already gone through an infinite number of cycles. He said that knowledge comes from the Buddha, one of whose names is lokavidū,
the “knower of worlds.” “The Buddha knew everything,” said Khema. He took out a pen and scribbled down some books I should read. His writing was slow and deliberate, like himself. We stopped talking. In the distance, I could hear the rise and fall of monks’ chanting, soft like the sound of the wind, unintelligible. I had no idea what time it was . . .
During my visit with Khema, he mentioned the Four Noble Truths of Buddhism: First, that life is filled with suffering. Second, that the origin of suffering is the craving and clinging to impermanent things. Third, that the suffering of life can be ended. And fourth, that the path to that end is through meditation, self-discipline, and mindful living. Although the Buddha first articulated the Four Noble Truths 2,500 years ago, Khema was careful to make clear that we come to these truths through our own experience with the world. But on other matters, such as their belief in the infinite cycles of the universe, Buddhists base their convictions exclusively on the words of the Buddha, a human being born as Siddhārtha Gautama, later known as the lokavidū,
the “knower of worlds.” I thought to myself: How do we know that the Buddha was the knower of worlds? Were Einstein and Darwin also knowers of worlds? The truths and laws that we believe about the physical and spiritual worlds—why do we believe them? And on what authority?
. . .
There are major differences in the truths of science and religion and the manner in which those truths are discovered. Unlike religion, science does not accept truths and laws based on the authority of divine beings or their designated emissaries or even from the institution of science as a whole. The ideas of great figures in science, such as Niels Bohr and Alexander von Humboldt and Claude Bernard, might be taken seriously for a time simply out of deference to those towering intellects, but eventually the ideas will be accepted or rejected based on experimental test. Similarly, the personal transcendent experience, while a vital source of truth in religion, is viewed with suspicion in science. Personal passion may be a motivation and pleasure for scientists in doing their work, but the only truths and results that are accepted by the scientific community are those that can be reproduced in different experiments by different scientists and rederived by different people from the same mathematical equations. Indeed, science goes out of its way to try to eliminate the personal from the process of acquiring knowledge.
Finally, we see strong differences between science and religion in the process of revision.
The core beliefs of religion—and indeed the ideals of any of the Absolutes—are not subject to change or revision. The wisdom of God or of the enlightened Buddha is absolute. It is perfect. So is the nature of permanence, of unity, of indivisibility, of absolute truth. These entities of the Absolute are not approximations, like Newton’s equations for gravity. They are exact. They are like perfect circles, eternal and unassailable. They are like the amrita,
the elixir of immortality. They are like Plato’s ideal forms.
. . .
One summer, we had two or three hummingbirds darting about the feeder we hung on the veranda at the south end of our house. I quietly watched them from a back window, afraid of scaring them off. The birds seem to defy gravity. They hover. They float. They are “air within the air,” said Pablo Neruda. They are a painter’s accents, splashes of color on the canvas of the world, with iridescent blue heads and ruby red throats, iridescent light green and saffron bodies, orangish tails. You can’t see the color of their wings because they are flapping back and forth 50 times per second. To supply oxygen for such an engine, the highest metabolism of almost all animals, the heart rate of a hummingbird is an incredible 1,300 beats per minute. Oxygen consumption per weight is ten times that of top human athletes.
You can actually calculate a lot of the design specs of the hummingbird from basic physics and biology. The hummingbird earns its living by being able to hover in midair while sucking the nectar from delicious flowers. How fast must it flap its wings to perform such an acrobatic feat? Slow-motion videos of hummingbirds show that their wings move in a rotary motion, changing shape and angle throughout each cycle. If you require that the bird achieve the require aerodynamic lift to support its weight, its wing tip must move at about 1,500 centimeters per second. That corresponds to a flapping rate of about 50 flaps per second, as observed.
You can also compute the required heart rate. A human being can flap its wings, i.e., arms, at about 4 times per second. (I have personally verified this result in front of my appalled students at MIT.) Since the heart rate of an exercising human is around 125 beats per minute, the required heart rate of an h-bird, needing 50 flaps per second, should be 50/4 times larger, or about 1,600 beats per minute. That number is pretty close to the figure observed. It’s all a matter of science, like the swing of a pendulum. It’s all material. But when I’m looking at the birds, suspended in space, I don’t think numbers or gravity. I just watch and am amazed.
Copyright © 2018 by Alan Lightman. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.