Theory Quotes

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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

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

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.

You see, I divide men into three categories: those who have a lot of money, those who have none at all and those who have a little. The first want to keep what they have: their interest is to maintain order; the second want to take what they do not have: their interest is to destroy the existing order and to establish one which is profitable to them. They each are realist, people with whom one can agree. The third group want to overthrow the social order to take what they do not have, while still preserving it so that no one takes away what they have. Thus, they preserve in fact what they destroy in theory, or they destroy in fact what they seem to preserve. Those are the idealists.

Jean-Paul Sartre

Einstein's relativity work is a magnificent mathematical garb which fascinates, dazzles and makes people blind to the underlying errors. The theory is like a beggar clothed in purple whom ignorant people take for a king... its exponents are brilliant men but they are metaphysicists rather than scientists.

There is no good theory of disease which does not at once suggest a cure.

Ralph Waldo Emerson

In theory one is aware that the earth revolves, but in practice one does not perceive it, the ground upon which one treads seems not to move, and one can live undisturbed. So it is with Time in one's life.

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

Don Basilio was a forbidding-looking man with a bushy moustache who did not suffer fools and who subscribed to the theory that the liberal use of adverbs and adjectives was the mark of a pervert or someone with a vitamin deficiency.

Carlos Ruiz Zafón

I don't mean to deny that the evidence is in some ways very strong in favor of your theory, I only wish to point out that there are other theories possible.

Arthur Conan Doyle

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

I cannot think of permanent enmity between man and man, and believing as I do in the theory of reincarnation, I live in the hope that if not in this birth, in some other birth I shall be able to hug all of humanity in friendly embrace.

Human life is a series of compromises, and it is not always easy to achieve in practice what one has found to be true in theory.

I would suggest to you the advantage, at present, of being very sparing in introducing theory in your papers (I formerly erred much in Geology in that way): let theory guide your observations, but till your reputation is well established be sparing in publishing theory. It makes persons doubt your observations. How rarely R. Brown ever indulged in theory: too seldom perhaps! Do not work too hard, and do not be discouraged because your work is not appreciated by the majority.

The field of experience is the whole universe in all directions. Theory remains shut up within the limits of human faculties.

Johann Wolfgang von Goethe

How empty is theory in the presence of fact!

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

Albert Einstein

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

It should be remembered, as an axiom of eternal truth in politics, that whatever power in any government is independent, is absolute also; in theory only, at first, while the spirit of the people is up, but in practice, as fast as that relaxes. Independence can be trusted nowhere but with the people in mass. They are inherently independent of all but moral law.

Thomas Jefferson

All our science is just a cookery book, with an orthodox theory of cooking that nobody's allowed to question, and a list of recipes that mustn't be added to except by special permission from the head cook.

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

Leonardo da Vinci

There may be no ultimate theory, and even if there is, we may not find it. But it is surely better to strive for a complete understanding than to despair of the human mind.

Stephen Hawking

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

Laws which are consistent in theory often prove chaotic in practice.

Napoleon I of France

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