A conception not reducible to the small change of daily experience is like a currency not exchangeable for articles of consumption; it is not a symbol, but a fraud.
A theory is no more like a fact than a photograph is like a person.
A theory is the more impressive the greater is the simplicity of its premises, the more different are the kinds of things it relates and the more extended the range of its applicability.
A young man is a theory, an old man is a fact.
Creating a new theory is not like destroying an old barn and erecting a skyscraper in its place. It is rather like climbing a mountain, gaining new and wider views, discovering unexpected connections between our starting points and its rich environment. But the point from which we started out still exists and can be seen, although it appears smaller and forms a tiny part of our broad view gained by the mastery of the obstacles on our adventurous way up.
Delight at having understood a very abstract and obscure system leads most people to believe in the truth of what it demonstrates.
Even for practical purposes theory generally turns out the most important thing in the end.
Every theory is a self-fulfilling prophecy that orders experience into the framework it provides.
Everything that explains the world has in fact explained a world that does not exist, a world in which men are at the center of the human enterprise and women are at the margin ''helping'' them. Such a world does not exist — never has.
Good tests kill flawed theories; we remain alive to guess again.
In order to shake a hypothesis, it is sometimes not necessary to do anything more than push it as far as it will go.
It is not enough for theory to describe and analyze, it must itself be an event in the universe it describes. In order to do this theory must partake of and become the acceleration of this logic. It must tear itself from all referents and take pride only in the future. Theory must operate on time at the cost of a deliberate distortion of present reality.
It is theory that decides what can be observed.
Let us work without theorizing, 'Tis the only way to make life endurable.
No theory is good unless it permits, not rest, but the greatest work. No theory is good except on condition that one use it to go on beyond.
One must credit an hypothesis with all that has had to be discovered in order to demolish it.
Socrates thought and so do I that the wisest theory about the gods is no theory at all.
Some theories are good for nothing except to be argued about.
The scientific theory I like best is that the rings of Saturn are composed entirely of lost airline baggage.
The temptation to form premature theories upon insufficient data is the bane of our profession.