The final chapter draws together some of the themes in Parts II and III. Locke, with his notion of ‘the same life’ and ‘the same consciousness’, which seems to be more than the mere succession of causally connected things, represents an almost Aristotelian organic account of the unity of substances. Both Hume and Plotinus thought that unity would have to be something more than this, but the latter believed in it and the former did not. Nevertheless, Plotinus did not think that physical objects were true unities, but that it was a projection of the unity that belonged to the self. This shares important features with Hume’s conventionalism, except that Hume did not believe in the unity of the self was there to be projected – substantial unity is, for him, pure convention or fiction. With the conclusions drawn in Part III we can see that the Plotinian view fits the facts.