Albert Einstein

"Owing to departures from strict homogeneity, the actual world cannot be exactly of Einstein's form. The instability of Einstein's universe indicates that in general, a system which is nearly, but not exactly, of this form will tend to depart further and further from it with lapse of time. Consequently, Einstein's model cannot permanently represent the smoothed-out universe of nebulae. It is possible, or course, that the actual universe was much closer to this model in the remote past than it is now. ...It has even been suggested that the Einstein configuration was an unstable equilibrium state through which the universe slowly passed in expanding from an initial 'explosive' phase of small volume and high density."

"In considering the structure of the universe... Einstein assumed... the irregularities in the distribution of matter can be neglected [i.e., the universe is homogeneous]. ...he noted that the largest velocities then assigned to the stars and nebulae were very small compared with the velocity of light. In 1917... the immense red-shifts of the farther nebulae were unknown. Einstein, therefore, considered a model of the universe in which matter was distributed in a uniform and continuous manner, the relative motion of the various parts being negligible [i.e., a static universe]. Following Seeliger, he found it impossible to regard the system as filling the whole of [infinite] Euclidean space. Also he could not regard the universe as an island in infinite space. For, in applying a well-known theorem of Boltzmann relating the densities at various points of space in which a distribution of particles is moving at random, he showed that zero density at the boundary would necessitate zero density at all points inside. Thus it appeared to Einstein that the universe as a whole could be neither infinite nor have a finite boundary. Hence space as a whole could not be Euclidean. ...In the classical picture time and space are distinct, time being infinite in duration and space Euclidean. In devising an alternative model Einstein retained this world-wide separation of time and space, despite the fusion of the two concepts in General Relativity, but he assumed that space as a whole was of the type known as spherical."

"The boys, who cannot grow up to adult human nature, are beating the prophets of the ancient race — Marx, Freud, Einstein — who have been tearing at our social, personal and intellectual roots, tearing with an objectivity which to the healthy animal seems morbid, depriving everything, as it seems, of the warmth of natural feeling. What traditional retort have the schoolboys but a kick in the pants? ... To our generation Einstein has been made to become a double symbol — a symbol of the mind travelling in the cold regions of space, and a symbol of the brave and generous outcast, pure in heart and cheerful of spirit. Himself a schoolboy, too, but the other kind — with ruffled hair, soft hands and a violin. See him as he squats on Cromer beach doing sums, Charlie Chaplin with the brow of Shakespeare... So it is not an accident that the Nazi lads vent a particular fury against him. He does truly stand for what they most dislike, the opposite of the blond beast — intellectualist, individualist, supernationalist, pacifist, inky, plump... How should they know the glory of the free-ranging intellect and soft objective sympathy to whom money and violence, drink and blood and pomp, mean absolutely nothing? Yet Albert and the blond beast make up the world between them. If either cast the other out, life is diminished in its force. When the barbarians destroy the ancient race as witches, when they refuse to scale heaven on broomsticks, they may be dooming themselves to sink back into the clods which bore them."

"Einstein explained his theory to me every day, and on my arrival I was fully convinced that he understood it."

"It was Einstein who had introduced almost all the revolutionary ideas underlying quantum theory, and who saw first what these ideas meant. His ultimate rejection of quantum theory was akin to Dr. Frankenstein’s shunning of the monster he had originally created for the betterment of mankind. Had Einstein not done so, in all likelihood he would be seen as the father of the modern theory."

"When we finally got our hands on the paper, we quickly realized that Einstein had put his finger on the essence of the problem and had delineated when it has a solution, before the invention of the modern quantum theory. Moreover, Einstein wrote with great lucidity about the subject, so that it seemed as if he were speaking directly to us, a century later. There was nothing dated or quaint about the analysis. For the first time in a long while, I found myself thinking, “Wow, this man really was a genius.”"

"Pondering about the problem, Einstein thought about the beam of light curving around the limb of the sun; he soon realized that it was not the beam that was bent, but rather the space through which it traveled. Matter must somehow curve space and other matter must move through this curved space in the way we see it move—yet this way must be "natural." He decided the most natural way would be along a path that represented the shortest distance between two given points in space (this is called the geodesic in mathematics). This would mean that the sun curves the space around it and the planets move in this space along geodesics. These geodesics appear to us to be elliptical orbits, but in curved space they are actually straight lines."

"Oh, he was a lovely man, Einstein. Oh, lovely man. He had the most perfect simplicity and perfect modesty, and all his feelings were humane."

"In the last twenty years of his life, Einstein's continued challenging of quantum theory was often dismissed as his being out of touch with modern physics. He was indeed wrong in denying the reality of the "spooky action" he discovered to lurk in quantum theory. Its existence, now called "entanglement," has been demonstrated. Nevertheless, Einstein is today recognized as the theory's most prescient critic. His constant claim that the theory's weirdness must not be brushed aside is borne out by today's proliferation of wild interpretations of quantum theory."

"I tried to persuade him to give up his determinism, which amounted to the view that the world was a four-dimensional Parmenidean block universe in which change was a human illusion, or very nearly so. (He agreed that this had been his view, and while discussing it I called him "Parmenides".) I argued that if men, or other organisms, could experience change and genuine succession in time, then this was real. It could not be explained away by a theory of the successive rising into our consciousness of time slices which in some sense coexist; for this kind of "rising into consciousness" would have precisely the same character as that succession of changes which the theory tries to explain away. ... I tried to present to Einstein-Parmenides as strongly as I could my conviction that a clear stand must be made against any idealistic view of time. And I also tried to show that, though the idealistic view was compatible with both determinism and indeterminism, a clear stand should be made in favor of an "open" universe — one in which the future was in no sense contained in the past or the present, even though they do impose severe restrictions on it. I argued that we should not be swayed by our theories to give up realism (for which the strongest arguments were based on common sense), though I think that he was ready to admit, as I was, that we might be forced one day to give it up if very powerful arguments (of Gödel's type, say) were to be brought against it. I therefore argued that with regard to time, and also to indeterminism (that is, the incompleteness of physics), the situation was precisely similar to the situation with regard to realism. Appealing to his own way of expressing things in theological terms, I said: if God had wanted to put everything into the world from the beginning, He would have created a universe without change, without organisms and evolution, and without man and man's experience of change. But He seems to have thought that a live universe with events unexpected even by Himself would be more interesting than a dead one."

"Summing up, we may say that there is hardly one among the great problems, in which modern physics is so rich, to which Einstein has not made an important contribution. That he may sometimes have missed the target in his speculations, as, for example, in his hypothesis of light quanta, cannot really be held too much against him, for it is not possible to introduce fundamentally new ideas, even in the most exact sciences, without occasionally taking risk."

"From a simple point of view, then, Einstein's equation can be written: tensor A = tensor B, where tensor A describes the curvature of space and tensor B describes the matter that causes the curvature. In practice, B can also contain terms describing an electromagnetic field since electromagnetic fields represent energy, and energy is just another form of mass. Einstein's dissatisfaction centered on tensor B."

"Napoleon, and other great men of his type, they were makers of empire. But there is an order of men that get beyond that: They are not makers of empire, but they are makers of universe. And when they have made those universes, their hands are unstained by the blood of any human being on earth. ... Ptolemy made a universe, which lasted 1400 years. Newton also made a universe, which has lasted 300 years. Einstein has made a universe, and I can't tell you how long that will last."

"Einstein's greatest legacy is not General Relativity, it's not quantum entanglement, and it's not slices of his brain either. It's a word: Gedankenexperiment – German for "thought experiment"."

"If light takes the path with the least time between two points, and light beams bend under the influence of gravity, then the shortest distance between two points is a curved line. Einstein was shocked by this conclusion: If light could be observed traveling in a curved line, it would mean that space itself is curved."

"Einstein independently discovered Riemann's original program, to give a purely geometric explanation to the concept of "force." ...To Riemann, the bending and warping of space causes the appearance of a force. Thus forces do not really exist; what is actually happening is that space itself is being bent out of shape. The problem with Riemann's approach... was that he had no idea specifically how gravity or electricity and magnetism caused the warping of space. ...Here Einstein succeeded where Riemann failed."

"We shall, therefore, assume the complete physical equivalence of a gravitational field and a corresponding acceleration of the reference system."

"The mass of a body is a measure of its energy content."

"Life is like riding a bicycle. To keep your balance you must keep moving."

"Lieber Habicht! / Es herrscht ein weihevolles Stillschweigen zwischen uns, so daß es mir fast wie eine sündige Entweihung vorkommt, wenn ich es jetzt durch ein wenig bedeutsames Gepappel unterbreche... / Was machen Sie denn, Sie eingefrorener Walfisch, Sie getrocknetes, eingebüchstes Stück Seele...?"

"Un homme heureux est trop content du présent pour trop se soucier de l'avenir."

"Whereas materialistic historians and philosophers neglect psychic realities, Freud is inclined to overstress their importance. I am not a psychologist, but it seems to me fairly evident that physiological factors, especially our endocrines, control our destiny ... I am not able to venture a judgment on so important a phase of modern thought. However, it seems to me that psychoanalysis is not always salutary. It may not always be helpful to delve into the subconscious. The machinery of our legs is controlled by a hundred different muscles. Do you think it would help us to walk if we analyzed our legs and knew exactly which one of the little muscles must be employed in locomotion and the order in which they work? ... I am not prepared to accept all his [Freud's] conclusions, but I consider his work an immensely valuable contribution to the science of human behavior. I think he is even greater as a writer than as a psychologist. Freud's brilliant style is unsurpassed by anyone since Schopenhauer."

"I believe that whatever we do or live for has its causality; it is good, however, that we cannot see through to it."

"Everything should be made simple as possible but no simpler."

"The only progress I can see is progress in the organization. The ordinary human being does not live long enough to draw any substantial benefit from his own experience. And no one, it seems, can benefit by the experiences of others. Being both a father and teacher, I know we can teach our children nothing. We can transmit to them neither our knowledge of life nor of mathematics. Each must learn its lesson anew."

"The moral decline we are compelled to witness and the suffering it engenders are so oppressive that one cannot ignore them even for a moment. No matter how deeply one immerses oneself in work, a haunting feeling of inescapable tragedy persists. Still, there are moments when one feels free from one's own identification with human limitations and inadequacies. At such moments, one imagines that one stands on some spot of a small planet, gazing in amazement at the cold yet profoundly moving beauty of the eternal, the unfathomable: life and death flow into one, and there is neither evolution nor destiny; only being."

"I am fascinated by Spinoza's pantheism, but I admire even more his contribution to modern thought because he is the first philosopher to deal with the soul and body as one, and not two separate things."

"Reading after a certain age diverts the mind too much from its creative pursuits. Any man who reads too much and uses his own brain too little falls into lazy habits of thinking, just as the man who spends too much time in the theater is tempted to be content with living vicariously instead of living his own life."

"The really good music, whether of the East or of the West, cannot be analyzed."

"The standard bearers have grown weak in the defense of their priceless heritage, and the powers of darkness have been strengthened thereby. Weakness of attitude becomes weakness of character; it becomes lack of power to act with courage proportionate to danger. All this must lead to the destruction of our intellectual life unless the danger summons up strong personalities able to fill the lukewarm and discouraged with new strength and resolution."

"Generations to come, it may well be, will scarce believe that such a man as this one ever in flesh and blood walked upon this Earth."

"Everyone who is seriously involved in the pursuit of science becomes convinced that some spirit is manifest in the laws of the universe, one that is vastly superior to that of man."

"I am happy because I want nothing from anyone. I do not care about money. Decorations, titles or distinctions mean nothing to me. I do not crave praise. The only thing that gives me pleasure, apart from my work, my violin, and my sailboat, is the appreciation of my fellow workers."

"All religions, arts and sciences are branches of the same tree. All these aspirations are directed toward ennobling man's life, lifting it from the sphere of mere physical existence and leading the individual towards freedom. It is no mere chance that our older universities developed from clerical schools. Both churches and universities — insofar as they live up to their true function — serve the ennoblement of the individual. They seek to fulfill this great task by spreading moral and cultural understanding, renouncing the use of brute force. The essential unity of ecclesiastical and secular institutions was lost during the 19th century, to the point of senseless hostility. Yet there was never any doubt as to the striving for culture. No one doubted the sacredness of the goal. It was the approach that was disputed."

"I claim credit for nothing. Everything is determined, the beginning as well as the end, by forces over which we have no control. It is determined for the insect as well as for the star. Human beings, vegetables or cosmic dust, we all dance to a mysterious tune, intoned in the distance by an invisible player."

"Our time is Gothic in its spirit. Unlike the Renaissance, it is not dominated by a few outstanding personalities. The twentieth century has established the democracy of the intellect. In the republic of art and science, there are many men who take an equally important part in the intellectual movements of our age. It is the epoch rather than the individual that is important. There is no one dominant personality like Galileo or Newton. Even in the nineteenth century, there were still a few giants who outtopped all others. Today the general level is much higher than ever before in the history of the world, but there are few men whose stature immediately sets them apart from all others."

"One may say "the eternal mystery of the world is its comprehensibility.""

"Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world. In our endeavor to understand reality we are somewhat like a man trying to understand the mechanism of a closed watch. He sees the face and the moving hands, even hears its ticking, but he has no way of opening the case. If he is ingenious he may form some picture of a mechanism which could be responsible for all the things he observes, but he may never be quite sure his picture is the only one which could explain his observations. He will never be able to compare his picture with the real mechanism and he cannot even imagine the possibility or the meaning of such a comparison. But he certainly believes that, as his knowledge increases, his picture of reality will become simpler and simpler and will explain a wider and wider range of his sensuous impressions. He may also believe in the existence of the ideal limit of knowledge and that it is approached by the human mind. He may call this ideal limit the objective truth."

"I never think of the future. It comes soon enough."

"My own career was undoubtedly determined, not by my own will but by various factors over which I have no control—primarily those mysterious glands in which Nature prepares the very essence of life, our internal secretions."

"The whole of science is nothing more than a refinement of every day [sic] thinking."

"I believe in intuitions and inspirations. I sometimes feel that I am right. I do not know that I am. When two expeditions of scientists, financed by the Royal Academy, went forth to test my theory of relativity, I was convinced that their conclusions would tally with my hypothesis. I was not surprised when the eclipse of May 29, 1919, confirmed my intuitions. I would have been surprised if I had been wrong."

"Science is international but its success is based on institutions, which are owned by nations. If therefore, we wish to promote culture we have to combine and to organize institutions with our own power and means."

"If A is success in life, then A = x + y + z. Work is x, play is y and z is keeping your mouth shut."

"Sometimes one pays most for the things one gets for nothing."

"I am not an Atheist. I do not know if I can define myself as a Pantheist. The problem involved is too vast for our limited minds. May I not reply with a parable? The human mind, no matter how highly trained, cannot grasp the universe. We are in the position of a little child, entering a huge library whose walls are covered to the ceiling with books in many different tongues. The child knows that someone must have written those books. It does not know who or how. It does not understand the languages in which they are written. The child notes a definite plan in the arrangement of the books, a mysterious order, which it does not comprehend, but only dimly suspects. That, it seems to me, is the attitude of the human mind, even the greatest and most cultured, toward God. We see a universe marvelously arranged, obeying certain laws, but we understand the laws only dimly. Our limited minds cannot grasp the mysterious force that sways the constellations. I am fascinated by Spinoza's Pantheism. I admire even more his contributions to modern thought. Spinoza is the greatest of modern philosophers because he is the first philosopher who deals with the soul and the body as one, not as two separate things."

"How can it be that mathematics, being, after all, a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality? Is human reason, then, without experience, merely by taking thought, able to fathom the properties of real things?"

"One reason why mathematics enjoys special esteem, above all other sciences, is that its laws are absolutely certain and indisputable, while those of other sciences are to some extent debatable and in constant danger of being overthrown by newly discovered facts."

"The meaning of relativity has been widely misunderstood. Philosophers play with the word, like a child with a doll. Relativity, as I see it, merely denotes that certain physical and mechanical facts, which have been regarded as positive and permanent, are relative with regard to certain other facts in the sphere of physics and mechanics. It does not mean that everything in life is relative and that we have the right to turn the whole world mischievously topsy-turvy."

"It has often been said, 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? Such might indeed be the right thing to do at a time when the physicist believes he has at his disposal a rigid system of fundamental laws which are so well established that waves of doubt can't reach them; but it cannot be right at a time when the very foundations of physics itself have become problematic as they are now. At a time like the present, when experience forces us to seek a newer and more solid foundation, the physicist cannot simply surrender to the philosopher the critical contemplation of theoretical foundations; for he himself knows best and feels more surely where the shoe pinches. In looking for an new foundation, he must try to make clear in his own mind just how far the concepts which he uses are justified, and are necessities."