Eienstein's Reality

As with Herbert Hoover, a notable change in the past three years has come over the public demeanor of Professor Albert Einstein. Whereas he was once almost as frozen and frightened in the presence of strangers and newshawks as was the onetime President of the U. S., the German mathematician now chuckles, gestures, jokes, smokes in public with considerable self-assurance. Last May Dr. Einstein made the short journey from Princeton to Philadelphia to receive the Franklin Medal of the Franklin Institute. A throng of scientists and dignitaries was assembled to hear what the medalist had to say. Einstein genially informed the chairman that he had nothing to say, that inspiration which he had awaited until the last moment had failed him. The chairman, much more embarrassed than the medalist, conveyed this information to the audience.

Explicitly to atone for his silence on that occasion, Dr. Einstein last week published in the Franklin Institute's Journal a bulky essay entitled "Physics and Reality" setting forth his own intuitive, emotional, thoroughly scientific view of the state of modern physics.

It has often been said, he began, and certainly not without justification, that the man of science is a poor philosopher. Why then should it not be the right thing for the physicist to let the philosopher do the philosophizing? . . . At a time like the present, when, experience forces us to seek a newer and more solid foundation, the physicist simply cannot surrender to the philosopher the critical contemplation of the theoretical foundations; for, he himself knows best, and feels more surely where the shoe pinches.

In other words, the nonscientific philosopher, though he may be dissatisfied with the trend of modern physics, is not well enough equipped to put his finger on the source of the trouble.

Science concerns the totality . . . of concepts directly connected with sense experiences, and theorems connecting them. In its first stage of development, science does not contain anything else.

Primitive science consists of a great mass of observed facts, a great number of attempts to connect one with another. But the connections (theorems) themselves have little interconnection. It is as if each existed in a different world, or as if the world itself had no logical unity. To a scientist this is repugnant. He accepts on faith that the world is a harmonious whole; he may choose any way he wishes to connect different phenomena; if he chooses the right one it will fall into place as naturally as a word in a puzzle, and no conceivable experiment will dislodge it.

Thus the body of science is like a pyramid. The broad base rests on sense impressions. As one proceeds farther & farther from sense impressions, fewer & fewer systems are necessary to explain Nature, since each system explains more. Thus mechanics and heat are merged when heat is revealed as molecular motion. But this is far from the pyramid's base; a hand dipped in hot water feels heat, not motion. The apex of the pyramid, not yet reached, would be a single system containing the terms necessary to describe all phenomena.

We now realize, with special clarity, how much in error are those theorists who believe that theory comes inductively from experience. Even the Great Newton could not free himself from this error ("Hypotheses non forgo").*

In other words, assembling a great mass of observed facts and stirring them around until a connecting theory emerges does not work. Speculation and intuition are supremely necessary. What sets Dr. Einstein apart is the quality of his intuition. There have been abler mathematicians than he. But from a very few observations--the constancy of light's speed in space and the equivalence of gravitational mass and inertia--he divined how the cosmos was made. He did not, like Newton, invent mathematics to describe it but borrowed the mathematics of Riemann, Fitzgerald, Lorentz and Minkowski.

At present man's closest penetration to the heart of reality is not single but double. Relativity deals with time, space, gravity, the finite speed of light; quantum mechanics with particles, electricity, the action of light. The two are not only separate but in some cases conflict. Relativity dispenses with the idea of absolute time; quantum mechanics retains it. Although it is a tremendously powerful approach to atomic behavior, quantum mechanics is shot through with uncertainty. It has given birth to the Uncertainty Principle of Heisenberg, which states that the position and velocity of an electron cannot be simultaneously ascertained. In the Schroedinger wave mechanics, the little symbol q is important. It stands, roughly, for statistical probability. Instead of locating the electron, it locates a region in which the electron probably occurs.

Is there any physicist who believes that we shall never get any inside view [of the behavior of single electrons]? To believe this is logically possible without contradiction; but it is so very contrary to my scientific instinct that I cannot forego the search for a more complete conception.

There is no doubt that quantum mechanics has seized hold of a beautiful element of truth, and that it will be a test stone for any future theoretical basis. . . . However, I do not believe that quantum mechanics will be the starting point in the search.

An approach from the relativistic starting point, on the other hand, has already made progress (TIME, July 15, et seq.). But so far only one particle at a time can be dealt with. Perhaps an intuitive genius of the future will find a new basis for unification-- a basis now lying in the abysm of the Unknown.

* "I do not make hypotheses."

This file is automatically generated by a robot program, so reader's discretion is required.