There is the theory... that you live in two places: You either live in fear, or you live in love.
Michael KeatonBlind commitment to a theory is not an intellectual virtue: it is an intellectual crime.
Imre LakatosMy theory about creativity is that the more money one has, the more creative one can be.
Robert MapplethorpeThere is no controversy within science over the core proposition of evolutionary theory.
Kenneth R. MillerIt is an acknowledged truth in philosophy that a just theory will always be confirmed by experiment.
Thomas Malthus