Theory Quotes

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The theory which I would offer, is simply, that as the land with the attached reefs subsides very gradually from the action of subterranean causes, the coral-building polypi soon raise again their solid masses to the level of the water: but not so with the land; each inch lost is irreclaimably gone; as the whole gradually sinks, the water gains foot by foot on the shore, till the last and highest peak is finally submerged.

When we descend to details, we can prove that no one species has changed (i.e., we cannot prove that a single species has changed): nor can we prove that the supposed changes are beneficial, which is the groundwork of the theory. Nor can we explain why some species have changed and others have not.

The patient, treated on the fashionable theory, sometimes gets well in spite of the medicine.

Thomas Jefferson

Although it may be difficult in theory to know what is just and equal, the practical difficulty of inducing those to forbear who can, if they like, encroach, is far greater, for the weaker are always asking for equality and justice, but the stronger care for none of these things.

Once we learn to expect theories to collapse and to be supplanted by more useful generalizations, the collapsing theory becomes not the gray remnant of a broken today, but the herald of a new and brighter tomorrow.

After Plotinus, says Schassler, fifteen centuries passed without the slightest scientific interest for the world of beauty and art.... In reality, nothing of the kind happened. The science of aesthetics … neither did nor could vanish, because it never existed. … the Greeks were so little developed that goodness and beauty seemed to coincide. On that obsolete Greek view of life the science of aesthetics was invented by men of the eighteenth century, and especially shaped and mounted in Baumgarten's theory. The Greeks (as anyone may read in Bénard's book on Aristotle and Walter's work on Plato) never had a science of aesthetics.

First you must have faith in an eternal world independent of you; then you must have faith in your ability to perceive it, and finally you must try to explain it by means of concepts or mathematical constructions. But don't always accept traditional concepts without reexamining them. Even overthrow my relativity theory, if you find a better one.... You must believe that the world was created as a unified whole which is comprehensible to man. Of course, it's going to take an infinitely long time to investigate this unified creation. But to me that is the highest and most sacred duty—unifying physics. Simplicity is the criterion of the universe.

Albert Einstein

With life and all I've been through, I do have a belief in goodness, a good spirit. I think what people have done with religion is personified good and evil, so good's become God with 'o' out, and evil's become Devil with a 'd' added. That's my theory of religion.

On the theory of natural selection we can clearly understand the full meaning of that old canon in natural history, 'Natura non facit saltum.' This canon, if we look only to the present inhabitants of the world, is not strictly correct, but if we include all those of past times, it must by my theory be strictly true.

"Thus, my friends," said Barbicane, "all motion suddenly stopped produces heat. And this theory allows us to infer that the heat of the solar disc is fed by a hail of meteors falling incessantly on its surface. They have even calculated - " "Oh, dear !" murmured Michel, "the figures are coming."

This mental activity, at first involuntary under the pressure of illness and suffering, gradually became second nature and led me finally to recognize that I was but an automaton devoid of free will in thought and action and merely responsible to the forces of the environment. Our bodies are of such complexity of structure, the motions we perform are so numerous and involved and the external impressions on our sense organs to such a degree delicate and elusive, that it is hard for the average person to grasp this fact. Yet nothing is more convincing to the trained investigator than the mechanistic theory of life which had been, in a measure, understood and propounded by Descartes three hundred years ago.

In theory, there is nothing the computer can do that the human mind can not do. The computer merely takes a finite amount of data and performs a finite number of operations upon them. The human mind can duplicate the process

Looking not to any one time, but to all time, if my theory be true, numberless intermediate varieties, linking most closely all the species of the same group together, must assuredly have existed; but the very process of natural selection constantly tends, as has been so often remarked, to exterminate the parent forms and the intermediate links. Consequently evidence of their former existence could be found only amongst fossil remains.

If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found the object of his search. … I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.

If the circulation of blood theory could not have been discovered without vivisection, the human kind could well have done without it.

Special relativity is so much a part not only of physics but of everyday life, that it is no longer appropriate to view it as the special "theory" of relativity. It is a fact.

It is difficult even to attach a precise meaning to the term "scientific truth." So different is the meaning of the word "truth" according to whether we are dealing with a fact of experience, a mathematical proposition or a scientific theory. "Religious truth" conveys nothing clear to me at all.

Albert Einstein

A theory if you hold it hard enough And long enough gets rated as a creed..

The supreme achievement would be to see that stating a fact is starting a theory.

Johann Wolfgang von Goethe

The rose is a rose, And was always a rose. But now the theory goes That the apple's a rose, And the pear is, and so's The plum, I suppose. The dear only knows What will next prove a rose. You, of course, are a rose But were always a rose.

The astonishment of life is the absence of any appearances of reconciliation between the theory and the practice of life.

Ralph Waldo Emerson

Science in England, in America, is jealous of theory, hates the name of love and moral purpose. There's revenge for this humanity.What manner of man does science make? The boy is not attracted. He says, I do not wish to be such a kind of man as my professor is.

Ralph Waldo Emerson

As philosopher of science Karl Popper has emphasized, a good theory is characterized by the fact that it makes a number of predictions that could in principle be disproved or falsified by observation.

Stephen Hawking

It is not easy to talk about how I reached the idea of the theory of relativity; there were so many hidden complexities to motivate my thought, and the impact of each thought was different at different stages in the development of the idea.

Albert Einstein

Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of facts will certainly reject my theory.