A Natural History of Time
by Pascal Richet
Translated by John Venerella
Chicago, 400 pp., $29
Saint Augustine got it right, confessing in The Confessions, "What, then, is time? If no one ask of me, I know; if I wish to explain to him who asks, I know not."
It might not do us much good to know what it is, since there's never enough of it anyway, but despite the timely contributions of Einstein and Bergson and Heidegger (Being and Time) and Hawking (A Brief History of Time) and Jorge Luis Borges, the Argentine fabulist who titled one of his conjectures "A New Refutation of Time," it remains a mystery as soon as we take the time to consider it carefully.
The mystery isn't solved, or even pursued, in Pascal Richet's A Natural History of Time. Richet, a professor of geophysics in Paris, doesn't concern himself with time as an enigma of philosophy or science, only with the history of efforts to figure out the age of the earth, the sort of time question that can be fairly conclusively answered. Until just the other day the earth was a lot older than it looked. After spending a few dozen pages on biblical chronologies, Richet devotes the rest of his book to the developments in geology and physics that, beginning in the 18th century, made it possible to figure out that the age of the earth is quite a few eons over 6,000 years, unless you're a creationist inhabiting your own planet.
The Greeks and Romans didn't care, because they had a cyclical concept of time. The world had no beginning and no end. Change was illusory, since the future was just a roundabout way of reverting to the past. If there was a real reality--a metaphysical reality, as in Plato--it was timeless and changeless. Inexhaustibly curious about other cultures and customs, the Greeks weren't curious about the distant natural past, and the Romans weren't curious, period. But a few philosophical pagan travelers did make observations about river sedimentation and volcanic activity that suggested long creative processes and time spans in nature.
The Hebrew Bible gave the creative process seven days. But as Richet points out, the important thing was not the the literal truth of the seven-day creation, which was a Babylonian-influenced story that superseded an older divine-creation story still embedded in Genesis; it was that the ancient Jews had introduced a beginning of time and hoped for an end.
The creation and the messianic prophecies were major new developments in the human sense of time, substituting linear for circular time. You might call it the invention of news. The Greeks and Romans had a chronic case of neophobia, and toward the end of the Hebrew Bible, the Greek-influenced Ecclesiastes announced that there was nothing new under the sun; but the novel thing about the Bible is the possibility of novelty--unique, irreversible events.
Christianity took it up and ran with it: "Gospel" means news. Time had a direction. History was a one-way road, with a starting point and an apocalyptic or millennial destination. The idea of progress was there somewhere. It was an original story, not a rerun.
But it was a short story for a long time. As late as the end of the 17th century, Bishop James Ussher was calculating that the world began the night before October 23, 4004 B.C., at about 6 P.M. And the Rev. William Whiston, in his runaway bestseller, A New Theory of the Earth, From its Original to the Consummation of All Things (1696), determined that the Flood was caused by a comet which brushed the earth on November 28, 2349 B.C., "at two o'clock in the morning, Beijing time, where Noah must have been living at that time," as Richet sums it up.
The word "geology" entered the language in 1760, and soon names like Hutton and Lamarck and Darwin and Kelvin did as well. Richet goes deeply into the scientific story, and what we get in effect is a detailed history of Western geology and physics that can be densely encyclopedic at times but, in broad outline, just renews your admiration for the unprecedented amount of knowledge a few diligent men in a few countries were able to accumulate in a little over a century.
At the end of the 18th century, scientists were still struggling to get out from under Genesis, and by the end of the 19th century, the table was set for Einstein and for the accumulation of geological and astronomical evidence that has given us a current estimate of the earth's age at about 4.5 billion years, which is Bishop Ussher multiplied by roughly 750,000.
Along the way Richet offers some lively thumbnail sketches of the scientists, such as Buffon (Georges-Louis Leclerc, Count of Buffon, Lord of Montbard, Marquis of Rougemont, Viscount of Quincy, and Vidame of Tonnerre), whose fortune allowed him to live undisturbed in monkish seclusion while devoting himself to inventing a new science, natural history. There was Darwin--a mediocre student whose father had told him, "You care for nothing but shooting, dogs, and rat-catching, and you will be a disgrace to yourself and all your family"--and Ernest Rutherford, who went from digging potatoes on a rugged pioneer farm in New Zealand to the top of British physics in a few years. Or Fritz Houtermans, a German physicist who had to survive detention and interrogation by both the Gestapo and the Soviet NKVD, and did so with both physics and sense of humor intact.
These sketches help scientifically semiliterate readers, like me, negotiate their way through the book, which gets increasingly technical as it goes on. But Richet never loses sight of his story, which is edifying and far from over, as scientists continue to thrash out the fiat lux of the Big Bang and the lights-out entropy perhaps looming 100 billion years or so in the future, as well as hypothetical alternate universes rising and disappearing in cyclical succession. The arguments reprise the old competing ideas of eternal worlds and unique creations, circular and linear time.
If there's a moral to the story, it's probably that time remains a riddle, and it's going to take forever to solve it.
Lawrence Klepp is a writer in New York.