  Ancient philosophy did not, of course, end with classical Stoicism, or indeed with the Hellenistic period, and neither did ancient theorizing about the soul. The revival of interest in the works of both Plato and Aristotle beginning in the second half of the second century B.C.  prominently included renewed interest in Platonic and Aristotelian conceptions of the soul, sparking novel theoretical developments, such as, for instance, Plotinus' argument (directed in particular against the Stoics) that the soul could not be spatially extended, since no spatially extended item could account for the unity of the subject of sense-perception (see Emilsson 1991).  Christian writers such as Clement of Alexandria and Gregory of Nyssa were heavily indebted to philosophical theories of soul, especially Platonic ones, but also introduced new concerns and interests of their own. Nevertheless, these and other post-classical developments in every case need to be interpreted within the framework and context furnished by the classical theories that we have been considering in some detail.