Theory Quotes

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A physical theory is not an explanation. It is a system of mathematical propositions, deduced from a small number of principles, which aim... to represent as simply, as completely, and as exactly as possible a group of experimental laws.

Arthur Conan Doyle

"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."

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.

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.

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

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.

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.

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.

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

Thomas Jefferson

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 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.

Such is professional jealousy; a scientist will never show any kindness for a theory which he did not start himself.

I cannot seriously believe in [the quantum theory] because it cannot be reconciled with the idea that physics should represent a reality in time and space, free from spooky actions at a distance.

Albert Einstein

Freedom is not merely a word or an abstract theory, but the most effective instrument for advancing the welfare of man.

John F. Kennedy

The error in positivism is that it takes as its standard of truth the contingently given division of labor, that between the science and social praxis as well as that within science itself, and allows no theory that could reveal the division of labor to be itself derivative and mediated and thus strip it of its false authority.

Theodor W. Adorno

It is said that this manifesto is more than a theory, that it was an incitement. Every idea is an incitement.

Oliver Wendell Holmes, Jr.

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

Albert Einstein

It might be that the biggest division in the world isn't men and women but folks who like cats and folks who like dogs" - (L.T.'s Theory of Pets)

In scientific investigations, it is permitted to invent any hypothesis and, if it explains various large and independent classes of facts, it rises to the ranks of a well-grounded theory.

To test a perfect theory with imperfect instruments did not impress the Greek philosophers as a valid way to gain knowledge.

Each time new experiments are observed to agree with the predictions the theory survives, and our confidence in it is increased; but if ever a new observation is found to disagree, we have to abandon or modify the theory.

Stephen Hawking

With all of its false assumptions and evil methods, communism grew as a protest against the hardships of the underprivileged. Communism in theory emphasized a classless society, and a concern for social justice, though the world knows from sad experience that in practice it created new classes and a new lexicon of injustice.

Martin Luther King, Jr.

It is well said, then, that it is by doing just acts that the just man is produced, and by doing temperate acts the temperate man; without doing these no one would have even a prospect of becoming good. But most people do not do these, but take refuge in theory and think they are being philosophers and will become good in this way, behaving somewhat like patients who listen attentively to their doctors, but do none of the things they are ordered to do.

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

Albert Einstein

One must first know an event before one can test a theory related to this event.

Albert Einstein