PREFACE

How does one interview oneself? How does one achieve distance, reverse one's perspective, see dispassionately that which surges up from within? If, as my wife Karen says with occasional dismay, I lack ego, does that make the task easier or harder? Strong egos are easier to limn, but diffuse egos may be more accessible.

Why does it only now occur to me that, born in 1920, my life is a defined segment of the twentieth century? That I am a twentieth-century man with values, perspectives, even emotions indigenous to, if not characteristic of, that era just as Samuel Johnson was an eighteenth-century man and Thomas Huxley a nineteenth-century man? Yet that thought has only just occurred to me. Perhaps because in the twentieth century, caught in the swirling tides of change, the future years always seemed so ill-defined. But now, as it draws to a close, its pattern takes form, as does that of my life—in either case, doubtless not the form one might have wished but a form imposed by the logic of chance and history.

Of course, I might well not have lived to my present age. As in every life, there have been moments of great danger, moments when my survival was highly uncertain and only fate decided. Of some of these, I was and am sharply aware, of others, perhaps blissfully, not. At least

three such are etched in my mind. Each was mercifully brief, each a confrontation with mortality.

When I was ten, on my way to school, I was struck by an automobile. I was knocked unconscious. Fortunately, the car was light and moving at moderate speed so I was pushed ahead of it some twenty to thirty feet and not run over or crushed. I recovered consciousness in a nearby doctor's office and, in the end, suffered only a slight concussion and severe bruises on the head and leg. What might have been . . . ?

One frigid morning during World War II, we took off from Bedford Airport outside Boston in a modified DC3 with a new radar system on board, bound for Eglin Field in Orlando, Florida. We expected to arrive by late afternoon. The pilot was navigating visually and by radio. I was tracking position easily on the radar.

Suddenly, over northern Maryland, one engine quit. We started to lose altitude. The pilot noted a nearby military airport but, on calling, ascertained that it was closed because office on the runway. As we therefore headed toward Baltimore Airport, the second engine quit. Although we had parachutes on board, we were by now too low to use them with satiny. The pilot circled back and descended toward the closed airport as our only plausible chance. We landed well on the runway, but braking was to no avail. The plane slid, veered off the runway, and finally abruptly jolted to rest when one wing caught the corner of a building. Although we had strapped ourselves into our seats, we were thrown about by the impact. My head was thrown into the radar gear, which inflicted several cuts and bruises, others were similarly hurt.

We had survived and fortunately the plane could be quickly repaired. The cause of the engine failures was determined to be water that had frozen at Bedford in the lines leading to the secondary gas tanks. A new wing section was bolted on and two days later we were again en route to Florida.

As a graduate student at MIT after World War II, I engaged in several research projects. One concerned measurement of the ultraviolet absorption spectra of nucleic acids and their molecular components at very low temperatures in liquid hydrogen (twenty-one degrees above absolute zero). The liquid hydrogen was contained within a quartz Dewar flask, constructed with plane quartz windows to allow transmission of the ultraviolet radiation. This Dewar was in turn immersed in a larger quartz Dewar, again with plane windows, which was filled with liquid nitrogen to insulate the liquid hydrogen from ambient temperature. The nucleic acid specimens would be immersed in the liquid hydrogen

in the path of an ultraviolet beam transmitted through the several quartz windows. While liquid nitrogen was available in our laboratory, liquid hydrogen had to be obtained from a physics laboratory in another building about a quarter of a mile away.

A wooden rack was built to hold the Dewars, which were filled with liquid nitrogen in our laboratory and covered over. I hand-carried the rack to the physics laboratory, where the liquid nitrogen in the inner Dewar was displaced with liquid hydrogen. I then carried the apparatus back to the ultraviolet source in our laboratory. One winter afternoon, I donned a heavy sweater and gloves and set out with the filled Dewars to the physics laboratory. On this day, the path was icy and uneven and, despite care, I slipped. The inner Dewar swung and bumped against the outer Dewar. In an instant both super-cold quartz vessels disintegrated explosively into a mass of minute quartz shards. Incredibly, the force of the explosion was entirely horizontal. Shards of quartz were enmeshed throughout my heavy woolen sweater. I was then twenty-seven. Had the explosion been upward, into my face. . . . Such moments, however banal, speak to each of us of fate, and finitude, and the narrow ledge on which humanity exists.

Conversely, in one's life there are moments of sheer delight when one could wish that time would stop and let the moment endure without end. As I am primarily a visual person, for me these moments come in the presence of surpassing natural beauty and peace, at scenes of wide expanse and steep heights and depth of color.

I remember a May morning along the Big Sur coast, standing amid wildflowers and gazing down on a serene ocean lapping at the rugged shore; a June morning at Rochers-de-Nouy above Montreux, looking down on the shimmering blue jewel of Lac Leman and across to the white slopes of Mont Blanc; the incredible blue of Crater Lake in July, surrounded by pines, still embedded in snow; the shadows and cliffs and rock spires of Canyon de Chelly at golden sunset; the acres of infinitely varied, magnificent tulips at Keukenhof in April, the wondrous soft purple of century-old rhododendron hedges in full bloom in June at Muckross Castle in Ireland. Each of these scenes created feelings of awe and thanks for such a place.

And yes, there have also been moments—days or weeks or months, really—of great anguish. For anguish is a slow emotion, a wound that heals only gradually and leaves an ever-tender scar.

Most of those I knees in my youth are now gone. All of my teachers are retired, if not deceased. Even the structures, the institutions, the patterns of life, if not gone, are vastly changed.

There is a salience to living memory that can never be captured in history books. When I was a boy, Civil War veterans still marched, if somewhat haltingly, in Fourth of July parades. World War I was history to me but freshly alive for the millions who had only a decade before participated in it. And so it is today for the Great Depression, World War II and the postwar years, even Kennedy and Vietnam—events richly alive to me but ancient history to the college students in my classes. In a few more years, all of it will be but dry pages in history texts or grainy films and strangely cadenced tapes.

For years, I have watched uncomprehendingly as my mentors, older colleagues, relatives, friends aged and grew old. Now it is my turn.

For my generation is dying. At the National Academy of Sciences annual meeting, the roll is called of those members who have passed away during the previous year. Formerly, these were the giants of whom I had read but knew only slightly. But now the names are those of my colleagues, those with whom I worked on boards and committees, those with whom I debated or collaborated, exchanged materials, planned meetings, shared evenings and food and drink. Colleagues of the great era of the "breakthrough," when biochemistry and biophysics broke through to the basic level of the gene to find there—in time—the clarifying answers to the enduring questions of biology. Soon the living memory' of those events will be gone, as will the living memory of science before World War II, of talent and knowledge freely given to the service of that war, and of the postwar revolution in the conduct of science.

And those of us who yet survive are fast passing into scientific obscurity, our contributions made, we are now irrelevant to the themes of the newer generations of science. "Who? Is he still alive?" Which is as it should be. C. P. Snow wrote, "The scientist has the future in his bones." I once did, in my twenties and thirties and forties. But now my perspectives, my instincts are dated. The future I foresaw has come to pass. A new future awaits and I am much less sure of its form. I read of persons who wish to be frozen in the hope that a more advanced technology will know how to revive them in a century or two. If that should

happen, however, they would know no one alive, they would be out of their time, with no shared experiences, wholly adrift, wholly alone.

But I would like to return, briefly, in a hundred years to see how science has resolved some of the questions, the mysteries, with which we wrestle today.

It has long been apparent that we do not enter this world as unformed clay, compliant to any mold; rather, we have in our beginnings some bent of mind, some shade of character. The origin of this structure—of the fiber in this clay—was for centuries mysterious. In earlier times, men sought its trace in the conjunction of the stars or perhaps in the momentary combination of the elements at nativity. Today, instead, we know to look within, seeking not in the stars but in our genes for the herald of our fate. Thus, we are each of us dealt a hand in life through our genes, our early family life, our schooling. It is idle to wish for another. How have I made use of the hand I was dealt?

I am grateful to the Alfred P. Sloan Foundation for having suggested this memoir as part of the Sloan Foundation Science Book Series and for its encouragement and support during the writing.