Ideas do not make a movement; they are themselves merely the product of concrete situations, the intellectual precipitate of particular conditions of life. Movements arise only from the immediate and practical necessities of social life and are never the result of purely abstract ideas. But they acquire their irresistible force and their inner certainty of victory only when they are vitalised by a great idea, which gives them life and intellectual content.
Anarcho-Syndicalism (1938)