θεωρία. A beholding, from
θεωρέε, to look at, to behold. Hence
theory comes to mean mental contemplation as distinguished from
practice, and knowledge is divided into theoretical and practical,
according as its end is merely speculative or to be carried out in
These, however, cannot always or generally be
kept separate. Mere theoretic knowledge, knowledge that
furnishes no guide to any sort of action, is a rarer possession
than might at first sight be imagined, if indeed such a
possession exists, while no practical art can be exercised
without some knowledge of means and of ends, of causes and
effects, which will come under the head of theory.
The theoretical and the practical life are, the one that of the
contemplative student, the other that of the man of business, of
politics, and of affairs.
These are the true meanings of the words theory and theoretic. The
making the former a synonym of conjecture is an abusive application of
it, though it is one largely made. Even so distinguished a man as Reid
is guilty of it.(1)
(1) See REID'S
Works, p. 97 and p. 235, Hamilton's ed.; and HAMILTON'S
Metaphysics, pp. 172, 174.