the distinction between past, present and future is only a stubborn illusion.”
Virtually everyone knows of one of Einstein’s ideas, that time may pass differently, depending upon the speed at which an object is moving, i.e., that time is relative to motion. At 99 percent of the speed of light, a month in a spaceship might be a year on earth. An imaginary space traveler might return to earth in what she thought was five years, only to find her friends and family had aged fifty or be all dead and gone. A movie that captured the public imagination decades ago, 2001: A Space Odyssey, had such a theme, and there have been numerous others since. There has been much silly stuff written about time travel; however, the universe may be strange beyond our imaginings.
There are additional ideas concerning the unevenness of time’s passage. In England’s Chester Cathedral is an inscription on the face of a clock, part of which reads: “When, as a child, I laughed and wept, time crept. When, as a youth, I dreamed and talked, time walked. When I became a full-grown man, time ran. And later, as I older grew, time flew.” All of us have known something of that. As kids, we waited for our parents to finish shopping and it “seemed like an eternity.” We have heard the elderly talk about how, for them, “time has flown.”
The Swedish paleontologist Björn Kurtén suggests that whether time seems to pass slowly or quickly is not, in fact, just seeming; rather, it depends upon our pace of living. Thus, he says, a child’s wound heals more rapidly, tied to bodily processes. He points out that a child makes decisions quickly, while the old take their time thinking it over; we may say this is due to experience and the wisdom of age, but it might reflect a different tempo of life, so that both are ruminating on the subject to about the same degree.
Kurtén suggests that time, for human beings, has something of a “logarithmic” character, the distance from year one to ten being as long as the distance from ten to one hundred. Thus, during one-half of our subjective lifetimes, we are children, illustrating why these are the teachable years.
Perhaps, says Kurtén, how time is experienced is relative to size, as well. Smaller animals live at a frantic pace. Although a generation for a shrew may be only a few weeks, it may “live” just as much as an elephant of seventy years, only at a much faster rate; the hearts of the two animals make about the same number of beats in a lifetime. A single day to a hummingbird with its frenetic metabolism would be as long and as full of experience as several months for a ponderous, huge animal with its slow heartbeat. So, experientially, do the mayfly and the Galapagos tortoise both “get the same?” Interesting, isn’t it?
We do continually transcend time by way of memory and imagination. Someone has said that a highbrow or intellectual is a person who looks at a sausage and thinks of Picasso. In a similar vein to that rather clever remark, a paleontologist looks at the ordinary crust of the earth with its rocky layers, which are as common and mundane as sausage is to breakfast, and sees therein the record of life on earth. All that separates the various beings in the passage of a billion years is time, and what is that? Henry David Thoreau wrote, “Time is but the stream I go a-fishing in. I drink at it; but while I drink I see the sandy bottom and detect how shallow it is. Its thin current slides away, but eternity remains. I would drink deeper, fish in the sky whose bottom is pebbly with stars.” He saw beyond mere measurement and chronology to time’s mystery.
The nature of time baffles all of us. A joke in paleontological circles concerns people on tour through a natural history museum in the southwestern United States. The guide told them, “These dinosaur skeletons, some of the earliest ones, are 200 million and three years old!” Everyone was amazed. “How can you be so precise?” they asked. He replied, “Well, when I got the job, they told me they were 200 million years old—and that was three years ago.”
It is nearly impossible to hold in the mind numbers of this magnitude and to see ourselves in relation to them. Of course, some make no attempt, something like the sailor who was asked the distance to the sun; he said, “It’s far enough away so that it will not interfere with anything I want to do in the Navy.” Locating our context in both space and time is central to our humanity but is far from easy. A sign outside an astronomy lab reads, “Caution: The study of astronomy may be hazardous to your sense of self-importance!” Concepts of deep time, like those of deep space, can be threatening for many people.
It is intimidating to consider that so much of earth’s history has gone on before we arrived. After all, we are accustomed to thinking and acting as if everything revolved around us. It used to be said of Frederick the Great that he loved music, but that this was not so much music as it was the flute, and not so much the flute as his flute. The story of the Garden of Eden is about the egocentricity of human nature. The Greek myth of Icarus, in pride flying too close to the sun, is concerned with it also. Bertrand Russell once said, “Every man would like to be God, if it were possible; some few find it difficult to admit the impossibility.”
One of the main principles of geology, the science of the earth, is that the forces of nature operate (with the exception of the occasional catastrophe) in a uniform manner, i.e., that the forces operating today are the same as the ones that have done so throughout earth’s history. Therefore, the landscape we see about us is mostly the result of the accumulated effects of small increments of change over time. A bit of rock falls off a cliff. The tiny amount of acid in rainwater eats away at the rock. Raindrops act as miniature bombs that blast small craters in soil, loosening bits to be carried away by every little rivulet to join creeks and rivers, carrying more and more and finally emptying into the oceans. And the key is the immensity of time.
James Hutton is often called the father of geology. In 1775, he presented a paper before the Royal Society in Edinburgh in which he laid out the following scenario: The everlasting hills would one day be gone, their elements being redistributed bit by tiny bit into other strata. Eventually, such deposits might be uplifted by forces deep within the earth to create hills and mountains once again. Looking into the earth’s crust, Hutton concluded that the present is the key to the past; the same processes at work now have been ceaselessly at work over long ages. “I find no vestige of a beginning and no prospect of an end,” he said. The time scale involved in the mechanisms of the earth is so vast as to be beyond all our imaginings.
Stand on the rim of the Grand Canyon and look down into that deep chasm and you are gazing at formations laid down as much as a billion years ago. John Wesley Powell, in 1869 the first one to float the Colorado River down the length of the Canyon, saw therein the angled roots of mountains that have been completely eroded away and then overlain by thousands of feet of horizontal strata. He came to see that mountains cannot long remain mountains but that they are ephemeral topographic forms, saying, “Geologically, all existing mountains are recent; the ancient mountains are gone.” The mile-deep strata in the Canyon with its shells in the limestone from ancient seas, basalt from volcanic flows ages ago, and the roots of those once mighty ranges all displace us from the center stage of earth’s history.
That is part of the explanation, I think, for all the contorted efforts of the so-called creationist movement to shoehorn all of geologic time into a mere 6,000–10,000 years. Deep time—460,000 times the larger number—hugely reduces the proportion of the play for our own scene to be enacted, and hubris cannot accept that consequence.
However, much has been going on without us. The philosopher Immanuel Kant wrote, as far back as 1775 (clearly groping for words with which to give expression to the scope of the vast processes of nature beginning to be explored in his time), “Millions and whole mountain ranges of millions of centuries will pass, within which forever new worlds will be formed.” The poets, also, expressed what science found, as did Walt Whitman: “Long and long has the grass been growing. Long and long has the rain been falling. Long and long has the globe been rolling ‘round.”
How can we begin to comprehend how the earth uses time? Radiometric dating of meteors, the oldest known rocks, gives an estimate of the age of the solar system at 4.6 billion years. By
