Without revolutionary theory there can be no revolutionary movement.

Without a revolutionary theory there cannot be a revolutionary movement.

Men act like brutes in so far as the sequences of their perceptions arise through the principle of memory only, like those empirical physicians who have mere practice without theory.

Notwithstanding these major arguments the wave theory initially did not meet with complete acceptance.

If diffraction or interference phenomena were to be sought it was therefore necessary, in accordance with the basic principles of wave theory, to select for the test arrangement far smaller decisive dimensions than those employed in corresponding tests with visible light.

My theory of hitting was just to watch the ball as it came in and hit it.

Internationalism is a social and political theory, a certain concept of how human society ought to be organized, and in particular a concept of how the nations ought to organize their mutual relations.

Internationalism is a community theory of society which is founded on economic, spiritual, and biological facts. It maintains that respect for a healthy development of human society and of world civilization requires that mankind be organized internationally.

Essential to the theory of evolution is the premise that everything has come into being by itself.

THE rich possess ample means to realize any theory they may chuse to adopt in the education of their children, regardless of the cost; but it is not so with him whose Subsistence is derived from industry.

The human species, according to the best theory I can form of it, is composed of two distinct races, the men who borrow and the men who lend.

My theory is to enjoy life, but the practice is against it.

Mr. DeMille's theory of sexual difference was that marriage is an artificial state for women. The want to be taken, ruled, raped. That was his theory.

There is no falsification before the emergence of a better theory.

Indeed, this epistemological theory of the relation between theory and experiment differs sharply from the epistemological theory of naive falsificationism.