ABSTRACT
Revolutionary theory is a synthesis of the experience of the working-class movement throughout all lands—the generalised experience. Of course theory out of touch with revolutionary practice is like a mill that runs without any grist, just as practice gropes in the dark unless revolutionary theory throws a light on the path. The immense importance attached by Lenin to theory is perhaps best shown by this, that he himself undertook the great task of generalising, on behalf of materialistic philosophy, the main achievements of science since the days of Engels, and of comprehensively criticising the anti-materialistic trends of certain Marxists. The theory of spontaneity is the theory of opportunism; the theory must bow before the spontaneity of the working-class movement; the theory which in practice amounts to a denial that the vanguard of the working class, the Party of the working class, can act as leader for the class as a whole.
