Argument Quote by Pope John Paul I

No particular theory may ever be regarded as absolutely certain.... No scientific theory is sacrosanct...

— Karl Popper

It is curious how often erroneous theories have had a beneficial effect for particular branches of science.

— Ernst Mayr

If we have a correct theory but merely prate about it, pigeonhole it and do not put it into practice, then that theory, however…

— Mao Zedong

Theorists have wonderful ideas which take years and years to be verified.

— David Gross

“Theory in any branch of science entails a risk of detachment from reality”

— Quammen, David

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

— Jules Verne

The important question is whether [a theory] is true, not whether envisioning an alternative is too intellectually painful to bear.

— J. D. Trout

We have reached a situation where a theory has been accepted as fact by some, and possible contrary evidence is shunted aside. [This is]…

— Robert Shapiro

I'm not sure what theory is, unless it's the pursuit of fundamental questions.

— David Antin

At any one time there is a natural tendency among physicists to believe that we already know the essential ingredients of a comprehensive theory…

— Val Logsdon Fitch

When that theory is isolated from known facts, it is likely not to be productive.

— Patricia Churchland

In the end, a theory is accepted not because it is confirmed by conventional empirical tests, but because researchers persuade one another that the…

— Fischer Black