Theory Quotes

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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.

Opinions based upon theory, superstition, and ignorance are not very precious.

In the Theory of Numbers it happens rather frequently that, by some unexpected luck, the most elegant new truths spring up by induction.

Carl Friedrich Gauss

Marxism is not only the theory of socialism, it is an integral world outlook, a philosophical system, from which Marx's proletarian socialism logically follows. This philosophical system is called dialectical materialism.

If you want to know the taste of a pear, you must change the pear by eating it yourself. If you want to know the theory and methods of revolution, you must take part in revolution. All genuine knowledge originates in direct experience.

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.

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

I believe what really happens in history is this: the old man is always wrong; and the young people are always wrong about what is wrong with him. The practical form it takes is this: that, while the old man may stand by some stupid custom, the young man always attacks it with some theory that turns out to be equally stupid.

G. K. Chesterton

Here is the world, sound as a nut, perfect, not the smallest piece of chaos left, never a stitch nor an end, not a mark of haste, or botching, or second thought; but the theory of the world is a thing of shreds and patches.

Ralph Waldo Emerson

Einstein is the only figure in the physical sciences with a stature that can be compared with Newton. Newton is reported to have said "If I have seen further than other men, it is because I stood on the shoulders of giants." This remark is even more true of Einstein who stood on the shoulders of Newton. Both Newton and Einstein put forward a theory of mechanics and a theory of gravity but Einstein was able to base General Relativity on the mathematical theory of curved spaces that had been constructed by Riemann while Newton had to develop his own mathematical machinery. It is therefore appropriate to acclaim Newton as the greatest figure in mathematical physics and the Principia is his greatest achievement.

Stephen Hawking

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

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.

No phenomenon can be explained in and of itself; only many comprehended together, methodically arranged, in the end yield something that could be regarded as theory. In Karl J. Fink

Johann Wolfgang von Goethe

The theory of free speech, that truth is so much larger and stranger and more many-sided than we know of, that it is very much better at all costs to hear everyone's account of it, is a theory which has been justified on the whole by experiment, but which remains a very daring and even a very surprising theory. It is really one of the great discoveries of the modern time.

G. K. Chesterton

All theory is against the freedom of the will; all experience for it.

On quantum theory I use up more brain grease (rough translation of German idiom) than on relativity.

Albert Einstein

Aesthetic theories arose one hundred fifty years ago among the wealthy classes of the Christian European world.... And notwithstanding its obvious insolidity, nobody else's theory so pleased the cultured crowd or was accepted so readily and with such absence of criticism. It so suited the people of the upper classes that to this day, notwithstanding its entirely fantastic character and the arbitrary nature of its assertions, it is repeated by the educated and uneducated as though it were something indubitable and self-evident.

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

It is the people, and not the judges, who are entitled to say what their constitution means, for the constitution is theirs, it belongs to them and not to their servants in office—any other theory is incompatible with the foundation principles of our government.

Theodore Roosevelt

The idea that our natural resources were inexhaustible still obtained, and there was as yet no real knowledge of their extent and condition. The relation of the conservation of natural resources to the problems of National welfare and National efficiency had not yet dawned on the public mind. The reclamation of arid public lands in the West was still a matter for private enterprise alone; and our magnificent river system, with its superb possibilities for public usefulness, was dealt with by the National Government not as a unit, but as a disconnected series of pork-barrel problems, whose only real interest was in their effect on the reëlection or defeat of a Congressman here and there—a theory which, I regret to say, still obtains.

Theodore Roosevelt

Partial knowledge is more triumphant than complete knowledge; it takes things to be simpler than they are, and so makes its theory more popular and convincing.

Friedrich Nietzsche

It has become a commonplace that aggressiveness also often has its roots in fear. I am inclined to think that this theory has been pushed too far. [...] The type of aggressiveness that is the outcome of timidity is not, I think, that which inspires great leaders; the great leaders, I should say, have an exceptional self-confidence which is not only on the surface, but penetrates deep into the subconscious.

Bertrand Russell

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.