Theory Quotes

Classical thermodynamics ... is the only physical theory of universal content which I am convinced ... will never be overthrown.

The sun had, in the meanwhile, sunk behind the Ettersberg. We felt in the wood the chill of the evening, and drove all the quicker to Wiemar, and to Goethe's house. Goethe urged me to go in with him for a while, and I did so. He was in an extremely engaging mood. He talked a great deal about his theory of colors, and of his obstinate opponents; remarking that he was sure that he had done something in this science.

All social life is essentially practical. All mysterious which lead theory to mysticism find their rational solution in human practice and in the comprehension of the practice.

A theory can be proved by experiment; but no path leads from experiment to the birth of a theory.

Practice should always be based upon a sound knowledge of theory.

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

Theories are usually the over-hasty efforts of an impatient understanding that would gladly be rid of phenomena, and so puts in their place pictures, notions, nay, often mere words.

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.

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

Psychology saves us from mistakes. It makes us more clear as to what we are about. We gain confidence in respect to any method which we are using as soon as we believe that it has theory as well as practice at its back.

It is the theory that decides what can be observed.

Thought and theory must precede all salutary action; yet action is nobler in itself than either thought or theory.

If the facts don't fit the theory, change the facts.

Philosophy, certainly, is some account of truths the fragments and very insignificant parts of which man will practice in this workshop; truths infinite and in harmony with infinity, in respect to which the very objects and ends of the so-called practical philosopher will be mere propositions, like the rest.

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

Economists are people who wonder if what works in reality can also work in theory.

...These healers...my intellect has been unable to assimilate their theories....But their facts are patent and startling; and anything that interferes with the multiplication of such facts, and with our freest opportunity of observing and studying them, will, I believe, be a public calamity.

Practical sciences proceed by building up; theoretical science by resolving into components.

The scientific theorist is not to be envied. For Nature, or more precisely experiment, is an exorable and not very friendly judge of his work. It never says "yes" to a theory. In the most favorable cases it says "Maybe," and in the great majority of cases simply "No." If an experiment agrees with a theory it means for the latter "Maybe," and if it does not agree it means "No." Probably every theory will some day experience its "No" - most theories, soon after conception.

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.

True works of art contain their own theory and give us the measurement according to which we should judge them.

As far as social-economic theory is concerned, I am still a Marxist

That is the way of the scientist. He will spend thirty years in building up a mountain range of facts with the intent to prove a certain theory; then he is so happy with his achievement that as a rule he overlooks the main chief fact of all-that all his accumulation proves an entirely different thing.

How empty is theory in the presence of fact!

The economists will have to revise their theories of value.

A perfect parent is a person with excellent child-rearing theories and no actual children.

Theory must mediate between all previous truths and certain new experiences

The most practical solution is a good theory.

Being engulfed in practice without delicate knowledge related to it, is in many ways like entering a ship without knowing where it is headed.

Gray are all the theories, But green is the tree of life.

How is Marxist-Leninist theory to be linked with the practice of the Chinese revolution? To use a common expression, it is by "shooting the arrow at the target". As the arrow is to the target, so is Marxism-Leninism to the Chinese revolution. Some comrades, however, are "shooting without a target", shooting at random, and such people are liable to harm the revolution.

In theory there is no difference between theory and practice. In practice there is.

A professor must have a theory as a dog must have fleas.

In theory, theory and practice are the same. In practice, they are not.

There is no such thing as abstract Marxism, only concrete Marxism... The Sinofication of Marxism - that is, making certain that its manifestation is imbued with Chinese peculiarities - is a problem that must be understood and solved by the party without delay.

He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.

In theory, practice should work like theory. In practice, it doesn't.

The more success the quantum theory has, the sillier it looks

Those who are enamoured of practice without science are like a pilot who goes into a ship without rudder or compass and never has any certainty of where he is going. Practice should always be based upon a sound knowledge of theory.

Well, it may be all right in practice, but it will never work in theory

The theory must not contradict empirical facts.

You know economists; they're the sort of people who see something works in practice and wonder if it would work in theory.

Affery, like greater people, had always been right in her facts, and always wrong in the theories she deduced from them.

It is necessary to master Marxist theory and apply it, master it for the sole purpose of applying it. If you can apply the Marxist-Leninist viewpoint in elucidating one or two practical problems, you should be commended and credited with some achievement.

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.

As soon as science has emerged from its initial stages, theoretical advances are no longer achieved merely by a process of arrangement. Guided by empirical data, the investigator rather develops a system of thought which, in general, is built up logically from a small number of fundamental assumptions, the so-called axioms. We call such a system of thought a theory. The theory finds the justification for its existence in the fact that it correlates a large number of single observations, and it is just here that the 'truth' of the theory lies.

Criticism - however valid or intellectually engaging - tends to get in the way of a writer who has anything personal to say. A tightrope walker may require practice, but if he starts a theory of equilibrium he will lose grace (and probably fall off).

The rose is a rose, And was always a rose.But the theory now goes That the apple's a rose.

The theoretical idea ... does not arise apart from and independent of experience; nor can it be derived from experience by a purely logical procedure. It is produced by a creative act. Once a theoretical idea has been acquired, one does well to hold fast to it until it leads to an untenable conclusion.

Mysticism is in fact the only criticism people cannot level against my theory.

Everything factual is, in a sense, theory. The blue of the sky exhibits the basic laws of chromatics. There is no sense in looking for something behind phenomena: they are theory.

A theory is the more impressive the greater the simplicity of its premises is, the more different kinds of things it relates, and the more extended is its area of applicability. Therefore the deep impression which classical thermodynamics made upon me. It is the only physical theory of universal content concerning which I am convinced that within the framework of the applicability of its basic concepts, it will never be overthrown.

There could be no fairer destiny for any physical theory than that it should point the way to a more comprehensive theory in which it lives on as a limiting case.

Experience without theory is blind, but theory without experience is mere intellectual play.

... on principle, it is quite wrong to try founding a theory on observable magnitudes alone. In reality the very opposite happens. It is the theory which decides what we can observe.

It is certainly not the least charm of a theory that it is refutable; it is precisely thereby that it attracts the more subtle minds. It seems that the hundred-times-refuted theory of the "free will" owes its persistence to this charm alone; some one is always appearing who feels himself strong enough to refute it.

When art critics get together they talk about Form and Structure and Meaning. When artists get together they talk about where you can buy cheap turpentine.

I pass with relief from the tossing sea of Cause and Theory to the firm ground of Result and Fact.

It must be conceded that a theory has an important advantage if its basic concepts and fundamental hypotheses are 'close to experience,' and greater confidence in such a theory is certainly justified. There is less danger of going completely astray, particularly since it takes so much less time and effort to disprove such theories by experience. Yet more and more, as the depth of our knowledge increases, we must give up this advantage in our quest for logical simplicity in the foundations of physical theory.

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