The transition from Badiou and Meillassoux to Malabou leads us away from a host capacity and to a host substance, namely the human brain. Chapter 3 argues that Malabou manages to avoid a host capacity account of the human by laying out, in her reading of Hegel, a notion of plasticity not as a uniquely human trait but as the possible transformation of all traits. This position harbours an irreducible ambiguity, however, between an escape from the host capacities approach and its hyperbolisation, and according to this latter reading what Malabou offers us is nothing more than a host meta-capacity. Nevertheless, her notion of plasticity does allow her to develop a figure of the human that is universal, material, monist and immanent to itself. In the second half of Chapter 3 I explore Malabou’s determination to initiate a new plastic encounter between philosophy and neuroscience, eschewing both the ‘cognitivist’ position of neuroscientist Jean-Pierre Changeux and the ‘Continental’ resistance to neuroscience of Paul Ricœur, in order to elaborate what she calls her own ‘neuronal materialism’ (Que faire de notre cerveau? 162/What Should We Do with Our Brain? 69) in terms of ‘destructive plasticity’. In an attempt to develop this neuronal materialism in a way that avoids plasticity becoming one more defunct metaphor of the human, I offer a reading of Malabou’s self not as a metaphor but as a movement or tension of metaphoricity.