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This was a more serious question, more difficult to answer. “Most of the time, Doug, no one would come through. It’s not a busy place. Mainly, I collect contemporary documents —books, newspapers, magazines—and pass them on.”
“To whom?” Catherine asked.
“People from a time very distant from my own. They look human, but they aren’t entirely. They created the tu
He wondered how much sense they would make of this. The real time travelers,’ Archer had said: as good a description as any. Ben always trembled a little on the occasions when he was required to interact with these beings. They were kindly and only somewhat aloof; but one remained conscious of the evolutionary gulf. “Please understand, much of this is as far beyond my comprehension as it may be beyond yours. All I really know are legends, passed down by people like myself—other custodians, other caretakers. Legends of the future, you might say.”
“Tell us some,” Archer said.
What this concerns (Ben explained) is life on earth.
Look at it in the context of geologic time.
In the primeval solar system the earth is fused into coherent shape by the collisions of orbiting planetesimals. It has a molten core, a skin of cooler rock. It exudes gases and liquids —carbon dioxide, water. In time, it develops an atmosphere and oceans.
Over the course of millions of years, life of a sort arises as vermiform crystalline structures in the porous rock of hot mineral-dense undersea vents. In time, these crystalline structures adapt to a cooler environment by incorporating proteins into themselves—so successfully that the crystalline skeleton is discarded and purely proteinoid life comes to dominate the primitive biosphere. RNA and DNA are adopted as a genetic memory and evolution begins in earnest.
An almost infinite diversity of structures compete against the environment. There will never again be such complexity of life on earth—the rest of evolution is a narrowing, a wi
The climate changes. Prokaryotic cells poison the atmosphere with oxygen. Continents ride tectonic plates across the magma. Life flows and ebbs in the long intervals between cometary impacts.
Mankind arises. It turns out that mankind, like the grasses, like the flowering plants, is one of those species capable of transforming the planet itself. It alters the climatic balance and might well have drowned in its own waste products, except for an extraordinary new ability to modify itself and to create new forms of life. These are parallel and complementary technologies. Mankind, dying, learns to make machines in its own image. It learns to change itself in fundamental ways. The two capabilities combine to generate a new form of life, self-reproducing but only marginally biological. It can be called human because there is humanity in its lineage; it’s the legitimate heir of mankind. But it’s as different from mankind as crystalline life from the rocks it was born in, or protein life from the rocky structures that preceded it. These new creatures are almost infinitely adaptable; some of them live in the ocean, some of them live in outer space. In their diaspora they occupy most of the planets of the solar system. They are very successful. They begin to comprehend, and eventually manipulate, some fundamental constants of the physical universe. They visit the stars. They discover hidden structures in the fabric of duration and distance.
Ben paused, a little breathless. How long since these mysteries had been explained to him? Years, he thought—no matter how you measure it. “Catherine,” he said, “would you open the window? There’s a nice breeze outside.” A little dazedly, she rolled back the blinds and lifted the window. “Thank you,” Ben said. “Very pleasant.”
Archer was frowning. “These new creatures,’ these are the folks who travel in time?”
“Who built the machine that operates in this house, yes. You have to understand what time travel means, in this case. They discovered what might be called crevices in the structure of space and time—fractures, if you like, with a shape and duration outside the definable bounds of this universe but intersecting it at certain points. A ‘time machine’ is a sort of artificial tu
Archer said, “Why here?”
“It’s a meaningless question. The nodes are natural features, like mountains. There are nodes that intersect the crust of the earth under the ocean, nodes that might open in thin air.”
“How many places like this are there, then?”
Ben shrugged. “I was never told. They tend to cluster, both in space and in time. The twentieth century is fairly rich in them. Not all of them are in use, of course. And remember: they have duration as well as location. A node might be accessible for twenty years, fifty years, a hundred years, and then vanish.”
Catherine had been sitting in patient concentration. She said, “Let me understand this. People a long way in the future open a pathway to these nodes, yes?”
Ben nodded.
“But why? What do they use them for?”
“They use them judiciously for the purpose of historical reclamation. This century—and the next, and my own—are the birthing time of their species. For them, it’s the obscure and distant past.”
“They’re archaeologists,” Catherine interpreted.
“Archaeologists and historians. Observers. They’re careful not to intervene. The project has a duration for them, also. Time passes analogously at both ends of the link. They’re conducting a two-hundred-year-long project to restore their knowledge of these critical centuries. When they’re finished, they mean to dismantle the tu
Catherine said, “Paradox?”
Archer said, “A time paradox. Like if you murder your own grandfather before you’re born, do you still exist?”
She regarded him with some astonishment. “How do you know that?”
“I used to read a lot of science fiction.”
Ben said, “I’m told there are tentative models. The problem isn’t as overwhelming as it seems. But no one is anxious to put it to the test.”
Archer said, “Even the presence of somebody from the future might have an effect. Even if they just crush a plant or step on a bug—”
Ben smiled. “The phenomenon isn’t unique to time travel. In meteorology it’s called ‘sensitive dependence on original conditions.’ The atmosphere is chaotic; a small event in one place might generate a large effect in another. Wave your hand in China and a storm might brew up in the Atlantic. Similarly, crush an aphid in 1880 and you might alter the presidential election of 1996. The analogy is good, Doug, but the co
“Attractors,” Archer supplied.
Ben was pleased. “You keep up with contemporary math?”
Archer gri
“I’ve been told there are similar structures in historical time—they tend to persist. But yes, the possibility for change exists. It’s an observer phenomenon. The rule is that the present is always the present. The past is always fixed and immutable, the future is always indeterminate—no matter where you stand.”
“From here,” Archer said, “the year 1988 is unchangeable”
“Because it’s the past.”
“But if I traveled three years back—”
“It would be the future, therefore unpredictable.”
“But there’s your paradox already,” Archer said. “It doesn’t make sense.”
Ben nodded. He had struggled with this idea himself … then submitted to it, a Zen paradox which happened to be true and therefore inarguable. “It’s the way time works,” he said. “If it doesn’t make sense, it’s because you haven’t made sense of it.”