I find that Mao's On Contradiction provides a much more revolutionary model for understanding the nature of contradictions. On the one hand, it responds to the failures of the Soviet model. Most importantly, it divorces dialectics from the metaphysical model handed down from Hegel by denying the "synthesis." Evidently, not all contradictions lead to a synthesis which is different from both aspects of the contradiction. After socialist transformation, proletariat and bourgeois continued to exist. I find that Mao's contributions account for this fact better than the traditional Marxian/Hegelian model.