Full Idea
Material force must be overthrown by material force. But theory also becomes a material force once it has gripped the masses.
Gist of Idea
Theory is as much a part of a revolution as material force is
Source
Karl Marx (Contrib to Critique of Hegel's Phil of Right [1844], Intro p.69), quoted by Peter Singer - Marx 4
Book Reference
Singer,Peter: 'Marx' [OUP 1996], p.20
A Reaction
A huge problem, I think, is that every theory (even conservatism) has to be simplified in a democracy if it is to grip the imagination of the majority. My current hatred is labels in political philosophy. They give us a cartoon view of the world.