Chapter Four – The theatre of the mind ‘The mind is a kind of theatre, where several perceptions successively make their appearance; pass, repass, glide away and mingle in an inﬁ nite variety of postures and situations.’ This is how the Scottish philosopher David Hume (1711-1776) described the mind, and certainly the idea of the mind as a theatre has a natural appeal. In Plato’s famous allegory of the cave, we humans do not directly see reality but are like prisoners in a dark cave who can watch only the shadows of people outside moving in front of a ﬁ re. Two thousand years later many psychological theories make use of the same metaphor. Yet Hume urged caution: ‘The comparison of the theatre must not mislead us,’ he said. ‘They are the successive perceptions only, that constitute the mind; nor have we the most distant notion of the place where these scenes are represented, nor of the material of which it is composed’ (Hume, 1739, section IV). In this chapter we will consider not just those places and materials but the lure, and the dangers, of the theatre metaphor.