Albert Einstein

“The mass of a body is a measure of its energy content.”

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

“...to the question whether or not the motion of the Earth in space can be made perceptible in terrestrial experiments. We have already remarked... that all attempts of this nature led to a negative result. Before the theory of relativity…”

“The most beautiful fate of a physical theory is to point the way to the establishment of a more inclusive theory, in which it lives on as a limiting case.”

“I lie on the beach like a crocodile and let myself be roasted by the sun. I never see a newspaper and don't give a damn for what is called the world.”

“We may assume the existence of an aether; only we must give up ascribing a definite state of motion to it, i.e. we must by abstraction take from it the last mechanical characteristic which Lorentz had still left it. ...…”

“I am neither a German citizen nor do I believe in anything that can be described as a "Jewish faith." But I am a Jew and glad to belong to the Jewish people, though I do not regard it in…”

“In Lenin I honor a man, who in total sacrifice of his own person has committed his entire energy to realizing social justice. I do not find his methods advisable. One thing is certain, however: men like him are the…”

“When a man after long years of searching chances on a thought which discloses something of the beauty of this mysterious universe, he should not therefore be personally celebrated. He is already sufficiently paid by his experience of seeking and…”

“[I do not] carry such information in my mind since it is readily available in books. ...The value of a college education is not the learning of many facts but the training of the mind to think.”

“I was sitting in a chair in the patent office at Bern when all of sudden a thought occurred to me: If a person falls freely he will not feel his own weight. I was startled. This simple thought made…”

“I have come to believe that the motion of the Earth cannot be detected by any optical experiment.”

“May they not forget to keep pure the great heritage that puts them ahead of the West: the artistic configuration of life, the simplicity and modesty of personal needs, and the purity and serenity of the Japanese soul.”

“Whether you can observe a thing or not depends on the theory which you use. It is the theory which decides what can be observed.”

“Try and penetrate with our limited means the secrets of nature and you will find that, behind all the discernible concatenations, there remains something subtle, intangible and inexplicable. Veneration for this force beyond anything that we can comprehend is my…”

“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 a determinist. As such, I do not believe in free will. The Jews believe in free will. They believe that man shapes his own life. I reject that doctrine philosophically. In that respect, I am not a Jew.”

“No one can read the Gospels without feeling the actual presence of Jesus. His personality pulsates in every word. No myth is filled with such life.”

“It is quite possible to be both. I look upon myself as a man. Nationalism is an infantile disease. It is the measles of mankind.”

“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.”

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

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

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

“I never think of the future. It comes soon enough.”

“Besides agreeing with the aims of vegetarianism for aesthetic and moral reasons, it is my view that a vegetarian manner of living by its purely physical effect on the human temperament would most beneficially influence a lot of mankind.”

“I believe in intuition and inspiration. ... At times I feel certain I am right while not knowing the reason. When the eclipse of 1919 confirmed my intuition, I was not in the least surprised. In fact I would have…”

“Everyone sits in the prison of his own ideas; he must burst it open, and that in his youth, and so try to test his ideas on reality.”

“I see a clock, but I cannot envision the clockmaker. The human mind is unable to conceive of the four dimensions, so how can it conceive of a God, before whom a thousand years and a thousand dimensions are as…”

“As an eminent pioneer in the realm of high frequency currents... I congratulate you on the great successes of your life's work.”

“What the inventive genius of mankind has bestowed upon us in the last hundred years could have made human life care free and happy if the development of the organizing power of man had been able to keep step with…”

“Without disarmament there can be no lasting peace. On the contrary, the continuation of military armaments in their present extent will with certainty lead to new catastrophies...For the creation of this public opinion in favor of disarmament every person living…”

“Only a life lived for others is a life worthwhile.”

“It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience.”

“I never failed in mathematics. Before I was fifteen I had mastered differential and integral calculus.”

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

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

“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.”

“Fundamental ideas play the most essential role in forming a physical theory. Books on physics are full of complicated mathematical formulae. But thought and ideas, not formulae, are the beginning of every physical theory. The ideas must later take the…”

“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…”

“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.”

“I cannot imagine a God who rewards and punishes the objects of his creation, whose purposes are modeled after our own — a God, in short, who is but a reflection of human frailty. Neither can I believe that the…”

“It is enough for me to contemplate the mystery of conscious life perpetuating itself through all eternity, to reflect upon the marvelous structure of the universe which we dimly perceive, and to try humbly to comprehend an infinitesimal part of…”

“Most of us prefer to look outside rather than inside ourselves; for in the latter case we see but a dark hole, which means: nothing at all.”

“Einstein's manner was full of charm and bonhomie. He enjoyed a joke and had many a jibe at the Nazi Professors, one hundred of whom in a book had condemned his theory. "Were I wrong," he said, "one professor would…”

“My political ideal is Democratic ... Force always attracts men of low morality.”

“All knowledge of reality starts from experience and ends in it. Propositions arrived at by purely logical means are completely empty as regards reality. Because Galileo saw this, and particularly because he drummed it into the scientific world, he is…”

“In the light of knowledge attained, the happy achievement seems almost a matter of course, and any intelligent student can grasp it without too much trouble. But the years of anxious searching in the dark, with their intense longing, their…”

“The pursuit of knowledge for its own sake, an almost fanatical love of justice and the desire for personal independence — these are the features of the Jewish tradition which make me thank my stars that I belong to it.”

“There is not the slightest indication that [nuclear energy] will ever be obtainable. It would mean that the atom would have to be shattered at will.”

“Try to become not a man of success, but try rather to become a man of value.”

“anti-Semitism is nothing but the antagonistic attitude produced in non-Jews by the Jewish group. This is a normal social reaction.”

“Great spirits have always encountered violent opposition from mediocre minds. The mediocre mind is incapable of understanding the man who refuses to bow blindly to conventional prejudices and chooses instead to express his opinions courageously and honestly.”

“The development during the present century is characterized by two theoretical systems essentially independent of each other: the theory of relativity and the quantum theory. The two systems do not directly contradict each other; but they seem little adapted to…”

“Perfection of means and confusion of goals seem—in my opinion—to characterize our age.”

“People like you and I, though mortal of course like everyone else, do not grow old no matter how long we live...[We] never cease to stand like curious children before the great mystery into which we were born.”

“Do not worry about your difficulties in Mathematics. I can assure you mine are still greater.”

“The only thing I can say is this: Only through permanent and faithful cooperation between the United States, Great Britain, and Russia can a lasting peace be secured.”

“In Russia the equality of all national and cultural groups is not merely nominal but is actually practiced.”

“Why is it nobody understands me and everybody likes me?”

“Certain it is that a conviction, akin to religious feeling, of the rationality or intelligibility of the world lies behind all scientific work of a higher order. ... This firm belief, a belief bound up with deep feeling, in a…”

“I received your letter of June 10th. I have never talked to a Jesuit priest in my life and I am astonished by the audacity to tell such lies about me. From the viewpoint of a Jesuit priest I am,…”

“The release of atomic energy has not created a new problem. It has merely made more urgent the necessity of solving an existing one.”

“That is simple, my friend. It is because Politics is more difficult than physics.”

“Today the atomic bomb has altered profoundly the nature of the world as we know it, and the human race consequently finds itself in a new habitat to which it must adapt its thinking.”

“Had I known that the Germans would not succeed in producing an atomic bomb, I would not have lifted a finger.”

“I am very smart. But not as strong-hearted as all the workers on earth for he toils endlessly and does it all to feed his family while I do it merely for solving an impossible puzzle.”

“It is easier to denature plutonium than it is to denature the evil spirit of man.”

“A new type of thinking is essential if mankind is to survive and move toward higher levels.”

“When I examine myself and my methods of thought I come to the conclusion that the gift of fantasy has meant more to me than my talent for absorbing positive knowledge.”

“I agree with your remark about loving your enemy as far as actions are concerned. But for me the cognitive basis is the trust in an unrestricted causality. "I cannot hate him, because he must do what he does." That…”

“Since the mathematicians have invaded the theory of relativity, I do not understand it myself anymore.”

“I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.”

“A new idea comes suddenly and in a rather intuitive way. But intuition is nothing but the outcome of earlier intellectual experience.”

“Never do anything against conscience even if the state demands it.”

“I have repeatedly said that in my opinion the idea of a personal God is a childlike one. You may call me an agnostic, but I do not share the crusading spirit of the professional atheist whose fervor is mostly…”

“Taken on the whole, I would believe that Gandhi's views were the most enlightened of all the political men in our time. We should strive to do things in his spirit... not to use violence in fighting for our cause,…”

“I believe that pipe smoking contributes to a somewhat calm and objective judgment in all human affairs.”

“One thing I have learned in a long life: that all our science, measured against reality, is primitive and childlike—and yet it is the most precious thing we have.”

“A truly rational theory would allow us to deduce the elementary particles (electron, etc.) and not be forced to state them a priori.”

“I think that only daring speculation can lead us further and not accumulation of facts.”

“What lead me more or less directly to the special theory of relativity was the conviction that the electromotive force acting on a body in motion in a magnetic field was nothing else but an electric field.”

“The strange thing about growing old is that the intimate identification with the here and now is slowly lost; one feels transposed into infinity, more or less alone, no longer in hope or fear, only observing.”

“Development of Western Science is based on two great achievements, the invention of the formal logical system (in Euclidean geometry) by the Greek philosophers, and the discovery of the possibility to find out causal relationships by systematic experiment (Renaissance). In…”

“It gives me great pleasure, indeed, to see the stubbornness of an incorrigible nonconformist warmly acclaimed.”

“To think with fear of the end of one's life is pretty general with human beings. It is one of the means nature uses to conserve the life of the species. Approached rationally that fear is the most unjustified of…”

“I’m a magnet for all the crackpots in the world, but they are of interest to me, too. A favourite pastime of mine is to reconstruct their thinking processes. I feel genuinely sorry for them, that’s why I try to…”

“If I would be a young man again and had to decide how to make my living, I would not try to become a scientist or scholar or teacher. I would rather choose to be a plumber or a peddler…”

“I made one great mistake in my life—when I signed the letter to President Roosevelt recommending that atom bombs be made; but there was some justification—the danger that the Germans would make them.”

“I have expressed an opinion on public issues whenever they appeared to me so bad and unfortunate that silence would have made me feel guilty of complicity.”

“Combinatory play seems to be the essential feature in productive thought — before there is any connection with logical construction in words or other kinds of signs which can be communicated to others.”

“Now he has departed from this strange world a little ahead of me. That means nothing. People like us, who believe in physics, know that the distinction between past, present, and future is only a stubbornly persistent illusion.”

“During that year in Aarau the question came to me: If one runs after a light wave with [a velocity equal to the] light velocity, then one would encounter a time-independent wavefield. However, something like that does not seem to…”

“The work on satisfactory formulation of technical patents was a true blessing for me. It compelled me to be many-sided in thought, and also offered important stimulation for thought about physics. Following a practical profession is a blessing for people…”

“That is simple my friend: because politics is more difficult than physics.”

“The conflict that exists today is no more than an old-style struggle for power, once again presented to mankind in semireligious trappings. The difference is that, this time, the development of atomic power has imbued the struggle with a ghostly…”

“The important thing is not to stop questioning. Curiosity has its own reason for existence. One cannot help but be in awe when he contemplates the mysteries of eternity, of life, of the marvelous structure of reality. It is enough…”

“It appears dubious whether a field theory can account for the atomistic structure of matter and radiation as well as of quantum phenomena.”

“In matters concerning truth and justice there can be no distinction between big problems and small; for the general principles which determine the conduct of men are indivisible. Whoever is careless with truth in small matters cannot be trusted in…”

“What is significant in one's own existence one is hardly aware, and it certainly should not bother the other fellow. What does a fish know about the water in which he swims all his life?”

“I live in that solitude which is painful in youth, but delicious in the years of maturity.”

“For scientific endeavor is a natural whole the parts of which mutually support one another in a way which, to be sure, no one can anticipate.”

“Intelligence makes clear to us the interrelation of means and ends. But mere thinking cannot give us a sense of the ultimate and fundamental ends. To make clear these fundamental ends and valuations, and to set them fast in the…”

“The highest principles for our aspirations and judgments are given to us in the Jewish-Christian religious tradition. It is a very high goal which, with our weak powers, we can reach only very inadequately, but which gives a sure foundation…”

“Ethical axioms are founded and tested not very differently from the axioms of science. Truth is what stands the test of experience.”

“I advocate world government because I am convinced that there is no other possible way of eliminating the most terrible danger in which man has ever found himself. The objective of avoiding total destruction must have priority over any other…”

“One strength of the communist system of the East is that it has some of the character of a religion and inspires the emotions of a religion. Unless the concept of peace based on law gathers behind it the force…”

“And certainly we should take care not to make the intellect our god; it has, of course, powerful muscles, but no personality. It cannot lead, it can only serve; and it is not fastidious in its choice of a leader.…”

“Great moral teachers of humanity were, in a certain sense, geniuses in the art of living more than in the art of thinking.”

“I want to go when I want. It is tasteless to prolong life artificially. I have done my share; it is time to go. I will do it elegantly.”