To be successful, insurrection must rely not upon conspiracy and not upon a party, but upon the advanced class. That is the first point. Insurrection must rely upon a revolutionary upsurge of the people. That is the second point. Insurrection must rely upon that turning-point in the history of the growing revolution when the activity of the advanced ranks of the people is at its height, and when the vacillations in the ranks of the enemy and in the ranks of the weak, half-hearted and irresolute friends of the revolution are strongest. That is the third point. And these three conditions for raising the question of insurrection distinguish Marxism from Blanquism.

Collected Works, Vol. 26, pp. 22–27.