The Hazards of Prophecy

With monotonous regularity, apparently competent men have laid down the law about what is technically possible or impossible -- and have been proved utterly wrong, sometimes while the ink was scarcely dry from their pens. On careful analysis, it appears that these debacles fall into two classes, which I will call Failures of Nerve and Failures of Imagination.

The Failure of Nerve seems to be the more common; it occurs when even given all the relevant facts, the would-be prophet cannot see that they point to an inescapable conclusion. Some of these failures are so ludicrous as to be almost unbelievable.

When the first locomotives were being built, critics gravely asserted that suffocation lay in wait for anyone who reached the awful speed of 30 miles an hour. Only 80 years ago, the idea of the domestic electric light was pooh-poohed by all the experts. When gas securities nose-dived in 1878 because Thomas Edison announced that he was working on the incandescent lamp, the British Parliament set up a committee to look into the matter. The distinguished witnesses reported, to the relief of the gas companies, that Edison's ideas were "good enough for our transatlantic friends ... but unworthy of the attention of practical or scientific men."

The most famous Failures of Nerve have occurred in the fields of aero- and astronautics. At the beginning of the 20th Century, scientists were almost unanimous in declaring that heavier-than-air flight was impossible, and that anyone who attempted to build airplanes was a fool.

Closer to the present, when the existence of the 200-mile-range V-2 was disclosed, there was considerable speculation about intercontinental missiles. This was firmly squashed by Dr. Vannevar Bush, the civilian general of the U.S. scientific war effort, in evidence before a Senate Committee on December 3, 1945. Listen:

"The people who have been writing these things that annoy me have been talking about a 3000-mile high-angle rocket shot from one continent to another, carrying an atomic bomb and so directed as to be a precise weapon which would land exactly on a certain target, such as a city.

"I say, technically, I don't think anyone in the world knows how to do such a thing, and I feel confident that it will not be done for a very long period of time to come.... I wish the American public would leave that out of their thinking."

The outcome was the greatest Failure of Nerve in all history. Faced with the same facts, American and Russian technology took two separate roads. The Russians, faced with the need for a 200-ton rocket, went ahead and built it. By the time it was perfected, it was no longer required for intercontinental rocketry; but with it they won the race into space.

Of the many lessons to be drawn from this slice of recent history, the one that I wish to emphasize is this: Anything that is theoretically possible will be achieved, no matter what the technical difficulties, if it is desired greatly enough.

The second kind of prophetic failure is less blameworthy. Failure of Imagination arises when all the available facts are appreciated and marshaled correctly -- but when the really vital facts are still undiscovered, and the possibility of their existence is not admitted.

One celebrated Failure of Imagination was that persisted in by Lord Rutherford, who laid bare the internal structure of the atom. Rutherford made fun of those who predicted that we should be (continued on page 342) Hazards of Prophecy (continued from page 133) able to harness the energy locked up in matter. Yet only five years after his death in 1937, the first chain reaction was started in Chicago. The wholly unexpected discovery of uranium fission had made it possible.

I have made a list of the inventions and discoveries that have been anticipated -- and those that have not. All the items listed below under The Unexpected have already been achieved or discovered.

Listed under The Expected, however, are concepts that have been around for hundreds or thousands of years. Some have been achieved; others will be; others may be impossible. But which?

The Unexpected

X rays

Nuclear energy

Radio, TV

Electronics

Photography

Sound recording

Quantum mechanics

Relativity

Transistors

Masers; lasers

Superconductors; superfluids

Atomic clocks; Mössbauer Effect

Determining composition of celestial bodies

Dating the past (carbon 14, etc.)

Detecting invisible planets

The ionosphere; Van Allen belt

The Expected

Automobiles

Flying machines

Steam engines

Submarines

Spaceships

Telephones

Robots

Death rays

Transmutation

Artificial life

Immortality

Invisibility

Levitation

Teleportation

Communication with the dead

Observing the past, the future

Telepathy

The Expected includes sheer fantasy as well as serious scientific speculation, because the only way of discovering the limits of the possible is to venture a little way past them into the impossible. As a first penetration of this area, I suggest that we scrutinize the question of invisibility.

The idea of invisibility, with all the power it would bestow upon anyone who could command it, is eternally fascinating; I suspect that it is one of the commonest of private daydreams. But it is a long time since it has appeared in adult science fiction, because it is a little too naïve for this sophisticated age. It smacks of magic, which is now out of fashion.

Yet invisibility is not one of those concepts that involve an obvious violation of the laws of nature; there are plenty of objects that we know exist yet cannot see. Most gases are invisible. I have never had the privilege of looking for a large diamond in a tumbler of water, but I have searched for a contact lens in a bath.

Transparency is a most unusual property of a few exceptional substances, arising from the internal disposition of their atoms. If their atoms were arranged differently, they would no longer be transparent -- and they would no longer be the same substances. You cannot take any compound at random and chemically torture it into transparency. And even if you could do so in the case of one particular compound, this would hardly help you to become an Invisible Man, for there are literally billions of unbelievably complex chemical compounds in the human body.

Moreover, the essential properties of many depend upon the fact that they are not transparent. If the light-sensitive chemicals at the back of the eye no longer trapped light, we should be unable to see; and if our flesh were transparent, the eye would be unable to function, since it would be flooded with radiation. You can't build a camera out of clear glass. Less obvious is the fact that the biochemical reactions upon which life depends would be thrown utterly out of balance, or would cease altogether. A man who achieved invisibility would not only be blind; he would be dead.

Many insects and land animals have developed remarkable powers of camouflage, but their disguise, being fixed, is effective only in the right surroundings. The greatest masters of deception are to be found in the sea. Flatfish and cuttlefish have an almost unbelievable control over the hues and patterns of their bodies and are able to change color within a few seconds when the need arises. A plaice lying on a checkerboard will reproduce the same pattern of squares on its upper surface, and is even reputed to make a creditable attempt at a Scots tartan.

The ability to match the scene behind you would be a kind of pseudo transparency, but it could fool only observers looking at you from a single direction. It works with the flatfish simply because it is flat and is trying to hide itself from predators swimming above it.

Another conceivable method of achieving invisibility is by means of vibrations. Vibrational invisibility is based on a familiar analogy: everyone knows how the blades of an electric fan vanish when the motor gets up speed. Well, suppose all the atoms of our bodies could be set vibrating or oscillating at a sufficiently high frequency.

The analogy is, of course, fallacious. We don't see through the fan blades, but past them; at every moment some of the background is uncovered, and at high enough speeds, persistence of vision gives us the impression that we have a continuous view. If the fan blades overlapped, they would remain opaque -- no matter how fast they were spinning.

And there is another unfortunate complication. Vibration means heat -- in fact it is heat -- and our molecules and atoms are already moving as fast as we can take. Long before a man could be vibrated into invisibility, he would be cooked.

The situation does not look promising; yet now comes a surprise: perhaps we have been approaching it from the wrong angle. Objective invisibility may be impossible -- but subjective invisibility is possible and has often been demonstrated.

An expert hypnotist can induce by posthypnotic suggestion what is known as a negative optical hallucination. This means that the subject will be unable to see a certain person, even if that person is standing in full view; the individual under hypnosis may eventually get hysterical if, for example, he sees what he believes are unattached articles such as a glass of champagne moving around the room -- carried, of course, by the invisible person.

This fact is almost as amazing as genuine invisibility would be, and it suggests that a person or object might be made effectively invisible to a fairly large group of people who were quite sure that they were in full possession of their senses. I advance this idea with some diffidence; but I have a hunch that if invisibility is ever achieved, it will be along these lines.

And I advance, with somewhat less diffidence, the suggestion that we have here a case in which there was a splendid opportunity for a Failure of Imagination. The leap that we took at the end of our examination of objective invisibility was where the imagination might have failed; that was where the temptation was great to declare categorically, "It can't be done." To be sure, the probability is overwhelming that it never will be done, but at least I have shown one way in which it might be done. I can be contacted by the Nobel Prize Committee through Playboy magazine.

What, then, about teleportation, levitation and other items on the list of expected but heretofore unrealized accomplishments? Throughout my inquiries into the limits of the possible, I have been aware of one primary hazard: the dangers of incredulity. For, as I glance down the Unexpected column, I am aware of a few items that, only ten years ago, I should have thought were impossible. Even as I write these words, my body is sleeted by billions of particles that I can neither see nor sense. Some of them -- unsuspected just a few years ago -- are sweeping upward in a silent gale through the solid core of the Earth itself. Before such marvels, incredulity is chastened; and it would be wise to be skeptical even of skepticism.