I am fascinated by time. Most of all by its mutability, which defies every “common sense” notion I have. I can remember some teacher in school drawing a graph on the blackboard, with something or other on the vertical axis and time on the horizontal axis. The teacher carefully put evenly spaced hash marks on the horizontal axis, showing the inevitable, steady cadence of the passing seconds. I can still remember how right that felt. The vertical axis was for measuring some unpredictable variable like velocity, while the dependable seconds of the horizontal axis spread it out for us to look at. Completely out of our control, time seemed like God’s own yardstick to measure the world.
Later, having made the unwise choice of a career in physics, I learned just how wildly irregular time could be when it is treated as just another dimension in space-time. In my new world, time acquired a completely undependable rubber band nature, stretching and shrinking and even reproducing itself into multiple dimensions, none of which agreed with one another. Time, I learned, was not merely relative, it seemed to have an arbitrary shiftiness that morphed and bred itself to suit the demands of whoever was writing the equations.
[You will, no doubt, be very happy to learn that I am not going to talk about all those skull-stretching notions any more in this column.]
Still, that background did give me a certain sympathy, when studying history, with people who had spent their entire lives accommodating themselves to the seasonal vagaries of solar time and were suddenly confronted with the mechanical dictatorship of an unchanging clock time. Imagine what it must have been like had you been some poor farm worker forced to take a factory job in the city. After having spent a lifetime rising with the sun and punctuating your days with meals controlled by your stomach, to suddenly find yourself commanded to appear at work each day when the town clock said “7.” One part of the year that might be only a little after sunrise, while in another part it was two hours and more later. That didn’t matter. All that mattered was for everyone to obey the machine in the square which sacrilegiously refused to march to God’s time.
We have invented terms like “paradigm shift” and the “shock of the new” to describe the nausea-inducing sense of disorientation human beings feel when something comfortable and certain suddenly decides to mutate into something new. Time has a way of doing that to us anyway, like the day when you look in the mirror and suddenly notice that the reflection is lots older than your self image or when you go back to your old neighborhood and discover it is unaccountably smaller than your memory says it once was.
But time can cause that same feeling of disorientation in other ways.
Had you been alive pretty much anywhere in the world around 1700, you would have had another good, solid, comfortable feeling: however quickly the human part of the world seemed to be changing (the human belief that things are changing too fast seems to be universal), the earth itself remained, history-less, firmly rooted outside the realm of time.
Had you been a Hindu, or a Buddhist, or a Mayan, or even a latter-day Platonist, you would have known that the earth had no beginning nor end. Rather, it lived in an endless series of cycles of time. Each cycle could be said to have a history all its own, but this was a meaningless notion as it would be succeeded by another cycle as if it had never been. People might have a useful history, but the earth and its cosmos were simply beyond the domain of time.
Had you been a good western Christian, you would have know that the world was created by God, as a single act, a few thousand years ago. There was some debate about how many thousand years ago, but the general consensus was that it was around 5,000 years. But the earth still had no real history. Time was not cyclical but linear, originating from a known moment. Created in that moment, the earth was simply the unchanging palate upon which God fabricated plants and animals and upon which the great moral struggle with Satan was taking place. Once again, people had histories, but the world, as the mere stage upon which the action took place, was outside of the action and beyond any useful idea of time.
Then along came those plaguey fossils. Pretty soon some clearly subversive types like Steno and Hooke and Buffon came along to suggest that the existence of different fossils in different layers of the earth suggested that those layers were deposited over time…a very long time. The most optimistic calculations of deposition rates were millimeters per year. The existing layers were already measured to be many miles thick (eventually it would reach an estimate of about sixty miles). This, in turn, seemed to imply that the comfortable, unhistorical earth was no more fixed than anything else. Earth existed in time and had a history all its own.
Talk about a play on the old query, “Did the earth move?!” It didn’t just move, it was suddenly whipped out from under. These iconoclasts were not only talking about the age of the earth and its history, they were changing the comfortable dimensions of time itself. Where once nothing could be older than a few thousand years, they were suddenly talking about hundreds of thousands, then millions, then hundreds of millions of years.
As an aside, it is arguable that this is precisely the time when the split between the average man and science first began. At this moment, from the end of the eighteenth century into the early nineteenth, science was truly popular. It had a readership and a following that it had never had before nor has had since. Fashionable people attended science lectures and popular journals reported at full length all the doings at the learned societies. Some experts, like Faraday and Lyell, even made a fair living lecturing to sold out crowds.
At this point in the history of human learning the distance between commonplace knowledge and science was not very large. And Faraday and Lyell had a talent for bridging it. Faraday devised spectacular experiments to demonstrate the newly discovered principles of electricity and magnetism to the general public. He left his audiences with the feeling that they really understood the subject. Lyell did the same for geology, using instructive displays of what were, after all, rocks. And anybody could comprehend rocks.
In fact, people did more than just attend lectures. This was the great age of the gifted amateur. England seemed to be crowded with enthusiastic amateurs, happily tramping the moors looking for fossils or puttering around in backroom laboratories. Often enough, they wrote up their results in papers that were duly read at the Royal Society or the British Association for the Advancement of Science. Even Faraday, a blacksmith’s son, had gotten his first scientific training by attending popular lectures.
The point is that in those early days a scientist (a specialized term not even invented until 1834) was assumed to be someone more or less like everyone else who dealt in things that could be understood, with enough effort, by just about anyone else.
But now there is a change. The general public found itself confronted with science grown suddenly alien. The human mind seems to be innately estranged by really big numbers. If it is comfortable with the idea of five thousand years, what happens when that grows to hundreds of thousands? Millions? Hundreds of millions?
Somewhere along in there, the mind simply balks. I talked earlier about how some ideas of time are real skull-stretchers. It is easy to imagine that part of the arcane training that converts normal people into scientists involves some sort of skull tenderizing process that allows their heads to stretch with an ease denied to the rest of us. How else can you explain their ability to comprehend concepts that simply give the rest of us headaches? Like numbers so big they have to be expressed in “scientific notation” (huge powers of ten)?
As a scientist of sorts myself, I can tell you it ain’t so. Horrendous numbers expressed in scientific notation are as incomprehensible, on an intuitive level, to a scientist as they are to anyone else. We are just too used to dealing with things we really don’t understand.
In that light, geology is much more honest than most sciences. They recognize that when they extended the time scale they were really introducing a whole new definition of time itself. Being good scientists, they invented a new jargon term to describe this new kind of time. They call it Deep Time.
What exactly is Deep Time?
That’s the part I like: Deep Time is shorthand for time longer than the human mind can comprehend. Now isn’t that refreshing?