Ought Quote by John Stuart Mill

Bad reasoning as well as good reasoning is possible; and this fact is the foundation of the practical side of logic.

— Charles Sanders Peirce

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

Good philosophy must exist, if for no other reason, because bad philosophy needs to be answered.

— Anonymous

Finding bad reasons for what one believes for other bad reasons - that's philosophy.

— Aldous Huxley

Theory, from whatever source, is not perfect until it is reduced to practice.

— Hosea Ballou

A theory is a good theory if it satisfies two requirements: it must accurately describe a large class of observations on the basis of…

— Stephen Hawking

“Clues put us on the right path toward a correct theory. Strong evidence is that which subsequently allows us to trust whether the theory…

— Carlo Rovelli

Our reasonings are grounded upon two great principles, that of contradiction, in virtue of which we judge false that which involves a contradiction, and…

— Gottfried Leibniz

I have this theory - that if we're told we're bad, then that's the only ideal we'll ever have.

— Jewel

To understand the theory which underlies all things is not sufficient. Theory is but the preparation for practice.

— James Stephens

In philosophy class I think we finally decided that 'good' is an infinitely recursive term - it can't be defined except in terms of…

— Orson Scott Card

“What we call ‘natural’ is frequently no more than bad theory.”

— Maurice Merleau-Ponty