1.
Whenever a theory appears to you as the only possible one, take this as a sign that you have neither understood the theory nor the problem which it was intended to solve.
Karl Popper
Whenever an explanation appears to be the only rational option, take this as a signal that you have not grasped the concept or the issue it was intended to address.
2.
A scientific theory is a tool and not a creed.
Joseph John Thomson
A scientific theory is an aid and not a dogma.
3.
Be ready to revise any system, scrap any method, abandon any theory, if the success of the job requires it.
Henry Ford
Be prepared to modify any process, abolish any technique, discard any concept, if achieving the goal necessitates it.
4.
The legal theory is, that marriage makes the husband and wife one person, and that person is the husband.
Lucretia Mott
5.
I'm a firm believer that in the theory that people only do their best at things they truly enjoy. It is difficult to excel at something you don't enjoy.
Jack Nicklaus
6.
Can you measure it? Can you express it in figures? Can you make a model of it? If not, your theory is apt to be based more upon imagination than upon knowledge.
Lord Kelvin
7.
I always had the theory that the most important thing is be happy, enjoy what are you doing, and be fresh mentally.
Rafael Nadal
8.
A theory that you can't explain to a bartender is probably no damn good.
Ernest Rutherford
9.
I am a misanthropic humanist... Do I like people? They're great, IN THEORY.
Bill Hicks
10.
There is a gulf between the high value Americans put on life in theory and its cheapness in practice.
Elizabeth Joan Smith
11.
We see the world in terms of our theories.
Thomas Kuhn
12.
There are many Christians who are Christians in theory only, and they are worldlings in practice.
John Alexander Dowie
13.
The Big Bang theory says nothing about what banged, why it banged, or what happened before it banged.
Alan Guth
14.
As for everything else, so for a mathematical theory: beauty can be perceived but not explained.
Arthur Cayley
16.
The greatest mathematicians, as Archimedes, Newton, and Gauss, always united theory and applications in equal measure.
Felix Klein
17.
I am even grateful to Einstein and others because through their erroneous theories they lead mankind away from that dangerous path I followed.
Nikola Tesla
18.
Skepticism must go hand in hand with rationality. When theories are shown to be false, the correct thing to do is to move on.
Brian Cox
19.
I just know that there are two theories when arguing with women. And neither one works.
John Marston
20.
I've got a theory: if you love your workspace, you'll love your work a little more.
Cynthia Rowley
21.
The farther the experiment is from theory, the closer it is to the Nobel Prize.
Irene Joliot-Curie
22.
I am not a fan of Sigmund Freud because his theories are not testicle.
Richard Wiseman
23.
Was Einstein's theory good? Relatively.
Bo Burnham
24.
A theory should not attempt to explain all the facts, because some of the facts are wrong
Francis Crick
25.
Being exposed to theory, stimulated by a basic love of concepts and mathematics, was a marvelous experience.
Rudolph A. Marcus
26.
[Knowledge is governed not by] a theory of knowledge, but by a theory of discursive practice.
Michel Foucault
27.
Learn your theories as well as you can, but put them aside when you touch the miracle of the living soul
Carl Jung
28.
My theory is children don't do what you tell them to do, they do what you do. You have to always do the right thing because they follow you.
Boman Irani
29.
The theory of marketing is solid but the practice of marketing leaves much to be desired.
Philip Kotler
31.
The end of science is not to prove a theory, but to improve mankind.
Manly Hall
33.
Change the instruments and you will change the entire social theory that goes with them
Bruno Latour
34.
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
Russell Kirk
36.
Einstein explained his theory to me every day, and on my arrival I was fully convinced that he understood it.
Chaim Weizmann
38.
Thought and theory must precede all action, that moves to salutary purposes. Yet action is nobler in itself than either thought or theory.
William Wordsworth
39.
There is nothing so practical as a good theory.
Kurt Lewin
40.
If facts conflict with a theory, either the theory must be changed or the facts.
Baruch Spinoza
41.
Leave your theories. All theories, you see, even those of virtue, are bad, foolish, mischievous.
Romain Rolland
42.
The power of a theory is exactly proportional to the diversity of situations it can explain.
Elinor Ostrom
43.
Brand is not a product, that's for sure; it's not one item. It's an idea, it's a theory, it's a meaning, it's how you carry yourself. It's aspirational, it's inspirational.
Kevin Plank
44.
The Bible is a statement, not of theories, but of actual facts... things are not true because they are in the Bible, but they are only in the Bible because they are true.
Hannah Whitall Smith
45.
In making theories, always keep a window open so that you can throw one out if necessary.
Bela Lugosi
48.
When you have two competing theories that make exactly the same predictions, the simpler one is the better.
William of Ockham
49.
The piano is a universal instrument. If you start there, learn your theory and how to read, you can go on to any other instrument.
Eddie Van Halen
50.
I have a theory that you can decide to make whatever day it is a good day.
Ryan Tedder