Time Travel. A History

We moved our hands, for example, when we were dwellers on the earth, and, in so doing, we gave vibration to the atmosphere which engirdled it. This vibration was indefinitely extended, till it gave impulse to every particle of the earth’s air, which thenceforth, and for ever, was actuated by the one movement of the hand. This fact the mathematicians of our globe well knew.

The actual mathematician Poe had in mind was the arch-Newtonian Pierre-Simon, Marquis de Laplace, for whom the past and the future were nothing more or less than physical states, rigidly connected by the inexorable mechanics of the laws of physics. The present state of the universe (he wrote in 1814) is “the effect of its past and the cause of its future.” Here is the Universe Rigid:

Given for one instant an intelligence which could comprehend all the forces by which nature is animated and the respective positions of the beings which compose it, if moreover this intelligence were vast enough to submit these data to analysis, it would embrace in the same formula both the movements of the largest bodies in the universe and those of the lightest atom; to it nothing would be uncertain, and the future as the past would be present to its eyes.

Some people already believed in such an intelligence; they called it “God.” To Him nothing would be uncertain or unseen. Doubt is for us mortals. The future, as the past, would be present to His eyes. (Or would it? Perhaps God would be content to see creation unfold. Heaven’s virtues might include patience.)

This one sentence by Laplace has more enduring life than the rest of his work combined. It pops up again and again in the philosophizing of the next two centuries. Whenever anyone starts talking about fate or free will or determinism, there is the marquis again. Jorge Luis Borges mentions his “fantasies”: “that the present state of the universe is, in theory, reducible to a formula, from which Someone could deduce the entire future and the entire past.”

The Time Traveller invents “an omniscient observer”:

To an omniscient observer there would be no forgotten past—no piece of time as it were that had dropped out of existence—and no blank future of things yet to be revealed. Perceiving all the present, an omniscient observer would likewise perceive all the past and all the inevitable future at the same time. Indeed, present and past and future would be without meaning to such an observer: he would always perceive exactly the same thing. He would see, as it were, a Rigid Universe filling space and time—a Universe in which things were always the same.^*4

“If ‘past’ meant anything,” he concludes, “it would mean looking in a certain direction; while ‘future’ meant looking the opposite way.”

The Universe Rigid is a prison. Only the Time Traveller can call himself free.

*1 He defined free love as “the liberation of individual sexual conduct from social reproach and from legal controls and penalties.” And he “practised it tirelessly,” as David Lodge wrote.

*2 Quid est ergo tempus? Si nemo ex me quaerat, scio; si quaerenti explicare velim, nescio.

*3 Predating them by several decades, a science-fiction writer named Ray Cummings put those words into the mouth of a character called the Big Business Man in his 1922 novel The Girl in the Golden Atom. Later, Susan Sontag said (quoting “an old riff I’ve always imagined to have been invented by some graduate student of philosophy”), “Time exists in order that everything doesn’t happen all at once, and space exists so that it doesn’t all happen to you.”

*4 This passage appears in an early serialized version in the New Review (volume 12, page 100) but not in the final book.

TWO

Fin de Siècle

Your body moves always in the present, the dividing line between the past and the future. But your mind is more free. It can think, and is in the present. It can remember, and at once is in the past. It can imagine, and at once is in the future, in its own choice of all the possible futures. Your mind can travel through time!

—Eric Frank Russell (1941)