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Prelude:
A Net Cast Over Time

The . . . silent, never-resting thing called time, rolling, rushing on, swift, silent, like an all-embracing ocean tide . . . this is forever very literally a miracle; a thing to strike us dumb.
--THOMAS CARLYLE, 1840

Not long ago I met a well-known surgeon dying in a hospital in Richmond, Virginia. He was a distressingly emaciated figure, his face a mask of skin over his skull, his hands a pale shade of purple from weeks of intravenous needles. Yet his voice remained deep and powerful, his eyes lively. When a friend asked how long he was going to be in the hospital this time, the surgeon said he didn't know, that time was becoming irrelevant to him. "It's ironic," he said, smiling weakly. "I lived by the calendar for sixty years. Beepers, schedules -- these things ruled my life. Now I have no idea what day it is, and this doesn't bother me. It's as if I am floating," he said, leaning back on crisp hospital sheets and almo st whispering the words.

Our obsession with measuring time is itself timeless. After self awareness, it may be our most distinctive trait as a species, since undoubtedly one of the first things we became self-aware about was our own mortality-the fact that we live and die in a set period of time.

Yet even in an age of measuring femtoseconds and star clusters 11 billion light-years away, time defies true objective measurement. It can seem to go slow and even stall out at certain moments only to brashly and breathlessly rush forward at others. Time can be wasted, kept, saved, spent, killed, lost, and longed for. To the Nuer herdsmen of southern Sudan, time is tot and mai, wet and dry, depending on the season. For Hesiod,the ancient Greek poet, time is harvesting cereals in the mouth when the cuckoo sings, and a low sex drive for men during the late summer, when "goats are at their fattest and the wine tastes best."

Consider the geometry of how we measure time. It can be divided into circle time and square time: clock time and calendar time. Clock time chases itself like Ouroboros, the hands or flashing numbers returning to the place where they started in a progression that has no beginning or end. It will continue in its cycle whether or not people are around to watch the hands and glowing numbers. In contrast, calendar time is made up of small boxes that contain everything that happens in a day, but no more. And when that day is over, you cannot return to that box again. Calendar time has a past, present, and future, ultimately ending in death when the little boxes run out.

Still, in modem times we take the mechanism of the calendar for granted, as we do breathing and the force of gravity. Passing through years, months, weeks, hours, minutes, and seconds without we seldom thinking about where these things carne from, or why we have chosen to divide time one way and not another.

It has not always been so. For thousands of years the effort to measure time and to create a workable calendar was one of the great struggles of humanity, a conundrum for astronomers, mathematicians, priests, kings, and anyone else who needed to count the days until the next harvest, to calculate when taxes were due, or to figure out the exact moment a sacrifice should be made to appease an angry god. A case can be made that science itself was first sparked by a human compulsion to comprehend the passing of time, to wrestle down the forward motion of life and impose on it some sense of order...

The effort to organize and control time continues unabated today. It is one of humankind's major collective efforts as we hedge our future and try to comprehend the past. In the stock market an investor sells a microchip stock short or long based on a broker's reading of the company's sales history. In river valleys we build dams and levees to prepare for 10-, 50-, and 100-year floods. We celebrate Easter, Passover, and Ramadan on prearranged dates just as our ancestors did centuries ago, and we expect our children will for centuries more to come.

We are a people of the calendar. Forward-and backward-looking, we are uncomfortable with the present in a way that our ancestors who tilled fields and lived and died according to the great cycles of nature would never have comprehended.

What are you doing at one o'clock tomorrow? Can you book me on the 2:06 flight to Memphis next Thursday? When will the inventory ship? Ten-nine-eight-seven-six-five-four-three-two-one-zero: blastoff!

Holding the surgeon's wasted hands in that Richmond hospital, I thought about my schedule for the rest of the day. Meetings, engagements, phone calls to make, a plane to catch to fly back home. I needed to pick up a small present for my eight-year-old, and I had to remember to put gas in my rental car before I turned it in at the airport. In a way I envied the doctor because he could let go and I could not. This is our blessing and our curse: to count the days and weeks and years, to calculate the movements of the sun, moon, and stars, and to capture them all in a grid of small squares that spread out like a net cast over time: thousands of little squares for each lifetime. How this net was woven over the millennia, and why, is the subject of this book.