Henry Ford
Industrialist
"Be ready to revise any system, scrap any method, abandon any theory, if the success of the job requires it."
Theory quotes
Theory
540 quotes on this topic — from poets, philosophers, and thinkers across history.
Bill Hicks
Comedian, Writer
"I am a misanthropic humanist... Do I like people? They're great, IN THEORY."
Elizabeth Joan Smith
Author
"There is a gulf between the high value Americans put on life in theory and its cheapness in practice."
Nikola Tesla
Inventor, Electrical Engineer
"I am even grateful to Einstein and others because through their erroneous theories they lead mankind away from that dangerous path I followed."
Irene Joliot-Curie
Physicist, Chemist
"The farther the experiment is from theory, the closer it is to the Nobel Prize."
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Topics related to Theory
Browse quotes that often appear alongside theory — connected by shared ideas and recurring themes.
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Theory quotes (page 1 of 27)
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"Learn your theories as well as you can, but put them aside when you touch the miracle of the living soul"
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"[Knowledge is governed not by] a theory of knowledge, but by a theory of discursive practice."
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"We ought not to endeavor to revise history according to our latter day notions of what things ought to have been, or upon the theory that the past is simply a reflection of the present"
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"Thought and theory must precede all action, that moves to salutary purposes. Yet action is nobler in itself than either thought or theory."
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"If facts conflict with a theory, either the theory must be changed or the facts."
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"Classical thermodynamics ... is the only physical theory of universal content which I am convinced ... will never be overthrown."
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"Bad critics judge a work of art by comparing it to pre-existing theories. They always go wrong when confronted with a masterpiece because masterpieces make their own rules."
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"Since the mathematicians have invaded the theory of relativity I do not understand it myself any more."
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"I've got this theory that there is a Volvo in any sane person's future."
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"How empty is theory in the presence of fact!"
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"My theory is that men are no more liberated than women."
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"In art, practice always comes before theory."
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"Other psychological theories say a good deal about compensation."
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"I think, you know, the thing everybody really wants to know anyway is not what the theory of relativity is, but I think what we all really want to know anyways, is whether we're loved or not."
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"Even theories must have foundations."
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"Any physical theory is always provisional, in the sense that it is only a hypothesis: you can never prove it."
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"It is the theory which decides what we can observe"
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"Theory is knowledge that doesn't work. Practice is when everything works and you don't know why."
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"Another thing I must point out is that you cannot prove a vague theory wrong."
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"A work in which there are theories is like an object which still has the ticket that shows its price."
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