Theory Quotes

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No fairer destiny could be allotted to any physical theory, than that it should of itself point out the way to the introduction of a more comprehensive theory, in which it lives on as a limiting case.

Albert Einstein

We do what we can, and then make a theory to prove our performance the best.

Ralph Waldo Emerson

It is essential to grasp the incontestable truth that a Marxist must take cognisance of real life, of the true facts of reality, and not cling to a theory of yesterday, which, like all theories, at best only outlines the main and the general, only comes near to embracing life in all its complexity.

Mind you, that you have a sound scientific theory to correlate your observations at the bedside. Mere experience by itself is nothing. If I take my dog to the bedside with me, he sees what I see. But he learns nothing from it. Why? Because he's not a scientific dog.

George Bernard Shaw

That, at any rate, is the theory of our Constitution. It is an experiment, as all life is an experiment.

Oliver Wendell Holmes, Jr.

We commonly say that the rich man can speak the truth, can afford honesty, can afford independence of opinion and action;--and that is the theory of nobility. But it is the rich man in a true sense, that is to say, not the man of large income and large expenditure, but solely the man whose outlay is less than his income and is steadily kept so.

Ralph Waldo Emerson

You must first propound the theory and then explain the practice.

Leonardo da Vinci

Of the general theory of relativity you will be convinced, once you have studied it. Therefore I am not going to defend it with a single word.

Albert Einstein

You cannot have a theory without principles. Principles is another name for prejudices.

Throughout the world, change is the order of the day. In every Nation economic problems, long in the making, have brought crises of many kinds for which the masters of old practice and theory were unprepared. In most Nations social justice, no longer a distant ideal, has become a definite goal, and ancient Governments are beginning to heed the call.
Thus, the American people do not stand alone in the world in their desire for change. We seek it through tested liberal traditions, through processes which retain all of the deep essentials of that republican form of representative government first given to a troubled world by the United States.

Franklin D. Roosevelt

How empty is theory in the presence of fact!

I would give absolutely nothing for the theory of Natural Selection, if it requires miraculous additions at any one stage of descent.

The truth of any knowledge or theory is determined not by subjective feelings, but by objective results in social practice. Only social' practice can be the criterion of truth. The standpoint of practice is the primary and basic standpoint in the dialectical-materialist theory of knowledge.

In the theory of psycho-analysis we have no hesitation in assuming that the course taken by mental events is automatically regulated by the pleasure principle. We believe, that is to say, that the course of those events is invariably set in motion by an unpleasurable tension, and that it takes a direction such that its final outcome coincides with a lowering of that tension that is, with an avoidance of unpleasure or a production of pleasure.

It is certainly not the least charm of a theory that it is refutable.

Friedrich Nietzsche

You have read and heard that communist theory-the science of communism created in the main by Marx, this doctrine of Marxism-has ceased to be the work of a single socialist of the nineteenth century, even though he was a genius, and that it has become the doctrine of millions and tens of millions of proletarians all over the world, who are applying it in their struggle against capitalism.

Geometry has been, throughout, of supreme importance in the theory of knowledge.

Bertrand Russell

If we have a correct theory but merely prate about it, pigeonhole it and do not put it into practice, then that theory, however good, is of no significance.

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.

Albert Einstein

The theory of the permanent revolution, in contradiction to the theory of socialism in one country, was recognized by the entire Bolshevik party during the period from 1917 to 1923.

When the theory of evolution destroyed the picture of God as the supreme Creator, confidence in God as the all-powerful Father of man fell with it, although many were able to combine a belief in God with the acceptance of the Darwinian theory.

The idea that physicists would in future have to study the theory of tensors created real panic amongst them following the first announcement that Einstein's predictions had been verified.

Bertrand Russell

In my relativity theory I set up a clock at every point in space, but in reality I find it difficult to provide even one clock in my room.

Albert Einstein

Those experienced in work must take up the study of theory and must read seriously; only then will they be able to systematize and synthesize their experience and raise it to the level of theory, only then will they not mistake their partial experience for universal truth and not commit empiricist errors.

Whenever a true theory appears, it will be its own evidence. Its test is, that it will explain all phenomena.

Ralph Waldo Emerson