There are times when the interests of the proletariat call for ruthless extermination of its enemies in open armed clashes.” - Vladimir Lenin

It is necessary to be able to withstand all this, to agree to any and every sacrifice, and even—if need be—to resort to all sorts of stratagems, manoeuvres and illegal methods, to evasion and subterfuges in order to penetrate the trade unions, to remain in them, and to carry on Communist work in them at all costs.

The basic question of every revolution is that of state power. Unless this question is understood, there can be no intelligent participation in the revolution, not to speak of guidance of the revolution.The highly remarkable feature of our revolution is that it has brought about dual power. This fact must be grasped first and foremost: unless it is understood, we cannot advance. We must know how to supplement and amend old "formulas".

As quoted in S. D. Mstislavskii (1925), Memoirs.