Theory Quotes

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"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.

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.

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.

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.

A priori one should expect a chaotic world which cannot be grasped by the mind in any way... The kind of order created by Newton's theory of gravitation...is wholly different. Even if the axioms of the theory are proposed by man, the success of such a project presupposes a high degree of ordering of the objective world.... That is the "miracle" which is being constantly reinforced as our knowledge expands.

Albert Einstein

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

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.

We do what we can, and then make a theory to prove our performance the best.

Ralph Waldo Emerson

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

How it happened that I in particular discovered the relativity theory, it seemed to lie in the following circumstance. The normal adult never bothers his head about space-time problems. Everything there is to be thought about it, in his opinion, has already been done in early childhood. I, on the contrary, developed so slowly that I only began to wonder about space and time when I was already grown up. In consequence I probed deeper into the problem than an ordinary child would have done.

Albert Einstein

This theory [quantum theory] reminds me a little of the system of delusions of an exceedingly intelligent paranoiac, concocted of incoherent elements of thoughts.

Albert Einstein

The theory of Communism may be summed up in the single sentence: Abolition of private property.

It is clear that the arm of criticism cannot replace the criticism of arms. Material force can only be overthrown by material force, but theory itself becomes a material force when it has seized the masses.

Although I'm regarded as a dangerous radical by particle physicists for proposing that there may be loss of quantum coherence, I'm definitely a conservative compared to Roger. I take the positivist viewpoint that a physical theory is just a mathematical model and that it is meaningless to ask whether it corresponds to reality. All that one can ask is that its predictions should be in agreement with observation. I think Roger [Penrose] is a Platonist at heart but he must answer for himself.

Stephen Hawking

No political party can possibly lead a great revolutionary movement to victory unless it possesses revolutionary theory and knowledge of history and has a profound grasp of the practical movement.

Such simple instincts as bees making a beehive could be sufficient to overthrow my whole theory.

Progress is Providence without God. That is, it is a theory that everything has always perpetually gone right by accident. It is a sort of atheistic optimism, based on an everlasting coincidence far more miraculous than a miracle.

G. K. Chesterton

We see that science is eminently perfectible, and that each theory has constantly to give way to a fresh one.

Theories are invigorating and tonic. Give me an ounce of fact and I will produce you a ton of theory by tea this afternoon.

Einstein's theory of relativity is probably the greatest synthetic achievement of the human intellect up to the present time.

Bertrand Russell

The theoretical scientist is compelled in an increasing degree to be guided by purely mathematical, formal considerations in his search for a theory, because the physical experience of the experimenter cannot lift him into the regions of highest abstraction.

Albert Einstein

By abstaining from all definite content, whether as formal logic and theory of science or as the legend of Being beyond all beings, philosophy declared its bankruptcy regarding concrete social goals.

Theodor W. Adorno