The previous chapter examined philosophically the idea of quantity-quality leaps, showing the notion to be implicated in the idea of history as a sequence of successive epochs matching the ordering of the categories in Hegel's Logic. In this chapter, we turn to Marx's idea of the transformation from capitalism to communism and ask whether it is compatible with this Hegelian-inspired metaphysics. As already intimated in the introduction to this book, to ascribe the notion of revolution as a quantity-quality leap directly to Marx is to tend towards wilful anachronism. Marx (1976b: 423) makes only a passing reference to the transformation when describing how at a quantitative tipping point the accumulation of capital can convert a master of trade into a capitalist – and this was perhaps just to placate Engels's desire to see more Hegelian flourishes in Capital. Furthermore, in Anti-Dühring (1936) and Dialectics of Nature (1941), Engels's concern is more to establish quantity to quality leaps as a general law of the dialectic dispelling static philosophies of nature than to present it as a way of thinking political events. Why then did the idea end up becoming the exemplary Marxist model of revolutionary change?

The answers to this question follow naturally from one another: the first being contingent on the strategic debates of early-twentieth-century social democracy; the second reflecting the dialectical mate-rialist vision of history given sanction by Engels's imprimatur. In the era of classical Marxism, the deployment of Hegel's notion fulfilled the goal of defending the compatibility of revolution and evolution against the gradualism advocated by Eduard Bernstein (1961). When Bernstein sought to emphasise the slow evolution of the socialist movement, condemning Marx's and Engels's revolutionism as a Blanquist throwback out of step with the practice of the German Social Democratic Party, Kautsky and Plekhanov defended the revolutionary imperative by reference to the Hegelian metaphysics of quantity-quality leaps.