Hegel occupies a peculiar temporal position in Marxism. From entering as an antagonist against whom Marx theorised the state (Marx 1975c), to being presented as an ambiguous methodological ally in Marx's Capital (Marx 1976b: 102–3), to the way he has received a full-blown resuscitation by thinkers from Georg Lukács (1971) to Slavoj Žižek (2012b), one is never sure whether to place Hegel at the origin or cutting edge of Marxist thought. To make things more difficult, the pivotal moment defining Hegel's influence arguably lies at neither end and can be located with the publication of Engels's Anti-Dühring in 1877 – the text which introduced Hegelian metaphysics to Marxist thought and which was pivotal for the interpretation of the doctrine by key theorists of the Second International such as Karl Kautsky and Georgi Plekhanov. The fact that Engels borrowed directly from Hegel the idea of quantity-quality leaps therefore compels us to begin this book with Hegel's philosophy itself. I thus save situating the idea of quantity-quality leaps with respect to the strategic and economic debates of early-twentieth-century Marxism for the following chapter. For the majority of this chapter, the focus is almost entirely philosophical in nature. We ask whether the idea of quantity-quality leaps escapes the philosophical commitments that Althusser (2005) and Colletti (1973) identify with the continuous, cumulative, and historicist structure of Hegel's dialectic.

In order to address this question, we turn to Hegel's Science of Logic. In particular, we observe those chapters concerned with grounding the idea of quantity-quality leaps in an attempted dialecticisation of the mathematical infinite. Given that these sections are among the most difficult of Hegel's already intimidatingly dense logico-ontological text, it should not come as a surprise that this transition has not been followed up systematically by Marxist thinkers.