Don't confuse hypothesis and theory. The former is a possible explanation; the latter, the correct one. The establishment of theory is the very purpose of science.
Martin H. Fischer

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

To an intellectual who is adrift in politics, a theory is an aim; to a true politician his theory is a boundary.
Francis Parker Yockey

The principal axiom in their theory was: Everything can be proved, and everything can be disproved; and in the process, one must profit as much from the folly of others, and from his own superiority, as he can.
Moses Mendelssohn

I learnt the theory of movement, which I still teach sometimes. I was very, very ambitious to learn a skill.
Diane Cilento

Because of the Turing completeness theory, everything one Turing-complete language can do can theoretically be done by another Turing-complete language, but at a different cost. You can do everything in assembler, but no one wants to program in assembler anymore.
Yukihiro Matsumoto

As you say, the way string theory requires all these extra dimensions and this comes from certain consistency requirements about how string should behave and so on.
Roger Penrose

It is also a good rule not to put overmuch confidence in the observational results that are put forward until they are confirmed by theory.
Arthur Eddington

This is the problem for which revolutionary theory has yet to find the right solution, if there is one. The difficulty is that the economic interests of the two classes are antagonistic.
Garet Garrett

In the absence of evidence, superstition. It's a Middle Ages thing. That's my theory anyway.
Tucker Carlson

String theory is an attempt at a deeper description of nature by thinking of an elementary particle not as a little point but as a little loop of vibrating string.
Edward Witten

Why has not anyone seen that fossils alone gave birth to a theory about the formation of the earth, that without them, no one would have ever dreamed that there were successive epochs in the formation of the globe.
Georges Cuvier

When I dealt with set theory, I could never make it be the music that I wanted.
Harrison Birtwistle

The whole action of the laws tended to increase the number of consumers of food and to diminish the number of producers, was due the invention of the Malthusian theory of population.
Henry Charles Carey

We have confirmed something we only knew in theory, namely that revolution, in which uncontrolled and uncontrollable forces operate imperiously, is blind and destructive, grandiose and cruel.
Frederica Montseny

Darwin based his theory on generalizations that were strictly empirical. You can go out and see that organisms do vary, that variations are inherited, and that every organism is capable of increasing its numbers in sufficiently favorable circumstances.
George C. Williams

So when you ask me how string theory might be tested, I can tell you what's likely to happen at accelerators or some parts of the theory that are likely to be tested.
Edward Witten

In this movement of colors I find the essence, which does not arise from a system, or an a priori theory.
Robert Delaunay

Sense data are much more controversial than qualia, because they are associated with a controversial theory of perception - that one perceives the world by perceiving one's sense-data, or something like that.
David Chalmers

There was a long history of speculation that in quantum gravity, unlike Einstein's classical theory, it might be possible for the topology of spacetime to change.
Edward Witten