 3.94–416. the soul’s constitution. The soul consists of two parts. The ‘spirit’ (anima) is spread throughout the body, while the ‘mind’ (animus) is the command centre, located in the chest. The soul in both aspects can be shown to be corporeal, Lucretius argues. Its characteristic sensitivity and mobility are explicable by the special combination of atoms that constitute it: it is a blend of the types of atoms constitutive of air, wind and fire, along with a fourth, ultra-fine type unique to soul. Although modern readers will find the details of this physiology hopelessly outdated, they can usefully replace Lucretian ‘mind’ and ‘spirit’ with, respectively, the brain and nervous system, in order to appreciate the enduring relevance of what follows, Lucretius’ argument that our conscious selves cannot survive death.