Billions & Billions (32 page)

In geophysics, plate tectonics was discovered—a set of conveyer belts under the Earth’s surface carrying continents from birth to death, and moving at a rate of about an inch a year. Plate tectonics is essential for understanding the nature and history of landforms and the topography of the sea bottoms. A new field of planetary geology has emerged in which the landforms and interior of the Earth can be compared with those of other planets and their moons, and the chemistry of rocks on other worlds—determined either remotely or from returned samples brought back by spacecraft or from meteorites now recognized as arising from other worlds—can be compared with the rocks on Earth. Seismology has plumbed the structure of the deep interior of the Earth and discovered beneath the crust a
semi-liquid mantle, a liquid iron core, and a solid inner core—all of which must be explained if we wish to know the processes by which our planet came to be. Some mass extinctions of life in the past are now understood by immense mantle plumes gushing up through the surface and generating lava seas where solid land once stood. Others are due to the impact of large comets or near-Earth asteroids igniting the skies and changing the climate. In the next century, at the very least we ought to be inventorying comets and asteroids to see if any of them has our name on it.

One cause for scientific celebration in the twentieth century is the discovery of the nature and function of DNA, deoxyribonucleic acid—the key molecule responsible for heredity in humans and in most other plants and animals. We have learned to read the genetic code and in increasing numbers of organisms we have mapped all the genes and know what functions of the organisms most of them are in charge of. Geneticists are well on their way to mapping the human genome—an accomplishment with enormous potential for both good and evil. The most significant aspect of the DNA story is that the fundamental processes of life now seem fully understandable in terms of physics and chemistry. No life force, no spirit, no soul seems to be involved. Likewise in neurophysiology: Tentatively, the mind seems to be the expression of the hundred trillion neural connections in the brain, plus a few simple chemicals.

Molecular biology now permits us to compare any two species, gene by gene, molecular building block by molecular building block, to uncover the degree of relatedness. These experiments have shown conclusively the deep similarity of all beings on Earth and have confirmed the general relations previously found by evolutionary biology. For example, humans and
chimpanzees share 99.6 percent of their active genes, confirming that chimps are our closest relatives, and that we share with them a recent common ancestor.

In the twentieth century for the first time field researchers have lived with other primates, carefully observing their behavior in their natural habitats, and discovering compassion, foresight, ethics, hunting, guerrilla warfare, politics, tool use, tool manufacture, music, rudimentary nationalism, and a host of other characteristics previously thought to be uniquely human. The debate on chimpanzee language abilities is still ongoing. But there is a bonobo (a “pigmy chimp”) in Atlanta named Kanzi who easily uses a symbolic language of several hundred characters and who has also taught himself to manufacture stone tools.

Many of the most striking recent advances in chemistry are connected with biology, but let me mention one that is of much broader significance: the nature of the chemical bond has been understood, the forces in quantum physics that determine which atoms like to link up with which other atoms, how strongly, and in what configuration. It has also been found that radiation applied to not implausible primitive atmospheres for the Earth and other planets generate amino acids and other key building blocks of life. Nucleic acids and other molecules in the test tube have been found to reproduce themselves and reproduce their mutations. Thus substantial progress has been made in the twentieth century toward understanding and generating the origin of life. Much of biology is reducible to chemistry and much of chemistry is reducible to physics. This is not yet completely true, but the fact that it is even a little bit true is a most important insight into the nature of the Universe.

Physics and chemistry, coupled with the most powerful computers on Earth, have tried to understand the climate and general circulation of the Earth’s atmosphere through time. This
powerful tool is used to evaluate the future consequences of the continued emission of CO
₂
and other greenhouse gases into the Earth’s atmosphere. Meanwhile, much easier, meteorological satellites permit weather prediction at least days in advance, avoiding billions of dollars in crop failures every year.

At the beginning of the twentieth century astronomers were stuck at the bottom of an ocean of turbulent air and left to peer at distant worlds. By the end of the twentieth century great telescopes are in Earth orbit peering at the heavens in gamma rays, X rays, ultraviolet light, visible light, infrared light, and radio waves.

Marconi’s first radio broadcast across the Atlantic Ocean occurred in 1901. We have now used radio to communicate with four spacecraft beyond the outermost known planet of our Solar System, and to hear the natural radio emission from quasars 8 and 10 billion light-years away—as well as the so-called black body background radiation, the radio remnants of the Big Bang, the vast explosion that began the current incarnation of the Universe.

Exploratory spacecraft have been launched to study 70 worlds and to land on three of them. The century has seen the almost mythic accomplishment of sending 12 humans to the Moon and bringing them, and over a hundred kilograms of moon rocks, back safely. Robotic craft have confirmed that Venus, driven by a massive greenhouse effect, has a surface temperature of almost 900° Fahrenheit; that 4 billion years ago Mars had an Earth-like climate; that organic molecules are falling from the sky of Saturn’s moon Titan like manna from Heaven; that comets are made of perhaps a quarter of organic matter.

Four of our spacecraft are on their way to the stars. Other planets have recently been found around other stars. Our Sun is revealed to be in the remote outskirts of a vast, lens-shaped galaxy comprising some 400 billion other suns. At the beginning
of the century it was thought that the Milky Way was the only galaxy. We now recognize that there are a hundred billion others, all fleeing one from another as if they are the remnants of an enormous explosion, the Big Bang. Exotic denizens of the cosmic zoo have been discovered that were not even dreamt of at the turn of the century—pulsars, quasars, black holes. Within observational reach may be the answers to some of the deepest questions humans have ever asked—on the origin, nature, and fate of the entire Universe.

Perhaps the most wrenching by-product of the scientific revolution has been to render untenable many of our most cherished and most comforting beliefs. The tidy anthropocentric proscenium of our ancestors has been replaced by a cold, immense, indifferent Universe in which humans are relegated to obscurity. But I see the emergence in our consciousness of a Universe of a magnificence, and an intricate, elegant order far beyond anything our ancestors imagined. And if much about the Universe can be understood in terms of a few simple laws of Nature, those wishing to believe in God can certainly ascribe those beautiful laws to a Reason underpinning all of Nature. My own view is that it is far better to understand the Universe as it really is than to pretend to a Universe as we might wish it to be.

Whether we will acquire the understanding and wisdom necessary to come to grips with the scientific revelations of the twentieth century will be the most profound challenge of the twenty-first.

S
ix times now have I looked Death in the face. And six times Death has averted his gaze and let me pass. Eventually, of course, Death will claim me—as he does each of us. It’s only a question of when. And how.

I’ve learned much from our confrontations—especially about the beauty and sweet poignancy of life, about the preciousness of friends and family, and about the transforming power of love. In fact, almost dying is such a positive, character-building experience that I’d recommend it to everybody—except, of course, for the irreducible and essential element of risk.

I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But as much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife, I know of nothing to suggest that it is more than wishful thinking.

I want to grow really old with my wife, Annie, whom I dearly love. I want to see my younger children grow up and to play a role in their character and intellectual development. I want to meet still unconceived grandchildren. There are scientific problems whose outcomes I long to witness—such as the exploration of many of the worlds in our Solar System and the search for life elsewhere. I want to learn how major trends in human history, both hopeful and worrisome, work themselves out: the dangers and promise of our technology, say; the emancipation of women; the growing political, economic, and technological ascendancy of China; interstellar flight.

If there were life after death, I might, no matter when I die, satisfy most of these deep curiosities and longings. But if death is nothing more than an endless dreamless sleep, this is a forlorn hope. Maybe this perspective has given me a little extra motivation to stay alive.

The world is so exquisite, with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there’s little good evidence. Far better, it seems to me, in our vulnerability, is to look Death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides.

For years, near my shaving mirror—so I see it every morning—I have kept a framed postcard. On the back is a penciled message to a Mr. James Day in Swansea Valley, Wales. It reads:

It’s signed with the almost-indecipherable initials of one William John Rogers. On the front is a color photo of a sleek, four-funneled steamer captioned “White Star Liner
Titanic.”
The postmark was imprinted the day before the great ship went down, losing more than 1,500 lives, including Mr. Rogers’s. Annie and I display the postcard for a reason. We know that “going grand” can be the most temporary and illusory state. So it was with us.

We were in apparent good health, our children thriving. We were writing books, embarking on ambitious new television and motion picture projects, lecturing, and I continued to be engaged in the most exciting scientific research.

Standing by the framed postcard one morning late in 1994, Annie noticed an ugly black-and-blue mark on my arm that had been there for many weeks. “Why hasn’t it gone away?” she asked. So at her insistence I somewhat reluctantly (black-and-blue marks can’t be serious, can they?) went to the doctor to have some routine blood tests.

We heard from him a few days later when we were in Austin, Texas. He was troubled. There clearly was some lab mixup. The analysis showed the blood of a very sick person. “Please,” he urged, “get retested right away.” I did. There had been no mistake.

My red cells, which carry oxygen all over the body, and my white cells, which fight disease, were both severely depleted. The most likely explanation: that there was a problem with the stem cells, the common ancestors of both white and red blood cells, which are generated in the bone marrow. The diagnosis was confirmed by experts in the field. I had a disease I had never heard of before, myelodysplasia. Its origin is nearly unknown. If I did nothing, I was astonished to hear, my chances were zero. I’d be dead in six months. I was still feeling fine—perhaps a little lightheaded from time to time. I was active and productive. The notion that I was on death’s doorstep seemed like a grotesque joke.

There was only one known means of treatment that might generate a cure: a bone marrow transplant. But that would work only if I could find a compatible donor. Even then, my immune system would have to be entirely suppressed so the donor’s bone marrow wouldn’t be rejected by my body. However, a severely suppressed immune system might kill me in several other ways—for example, by so limiting my resistance to disease that I might fall prey to any passing microbe. Briefly I thought about doing nothing and waiting for the advance in medical research to find a new cure. But that was the slimmest of hopes.

All our lines of research as to where to go converged on the Fred Hutchinson Cancer Research Center in Seattle, one of the premier institutions for bone marrow transplant in the world. It is where many experts in the field hang their hats—among them
E. Donnall Thomas, the winner of the 1990 Nobel Prize in Physiology and Medicine, for perfecting the present techniques of bone marrow transplantation. The high competence of doctors and nurses, the excellence of the care, fully justified the advice we were given to be treated at “the Hutch.”

The first step was to see if a compatible donor could be found. Some people never find one. Annie and I called my only sibling—my younger sister, Cari. I found myself allusive and indirect. Cari didn’t even know I was ill. Before I could get to the point, she said, “You got it. Whatever it is … liver … lung.… It’s yours.” I still get a lump in my throat every time I think of Cari’s generosity. But there was of course no guarantee that her bone marrow would be compatible with mine. She underwent a series of tests, and one after another, all six compatibility factors matched mine. She was a perfect match. I was incredibly lucky.