Noun
A doctrine, or scheme of things, which terminates in speculation or contemplation, without a view to practice; hypothesis; speculation.
An exposition of the general or abstract principles of any science; as, the theory of music.
The science, as distinguished from the art; as, the theory and practice of medicine.
The philosophical explanation of phenomena, either physical or moral; as, Lavoisier's theory of combustion; Adam Smith's theory of moral sentiments.
Source: Webster's dictionaryYour theory is crazy, but it's not crazy enough to be true. Niels Bohr
Democracy is the theory that the common people know what they want, and deserve to get it good and hard. H. L. Mencken
Anyone who is not shocked by quantum theory has not understood it. Niels Bohr
Experience is more important than theory. Italian Proverb
Theory dominates practice. Corsican Proverb
An ounce of experience is worth a pound of theory. Vermont Proverb