When it comes to the crunch, how does one know what other people are thinking, feeling etc? One way — the classical modern-philosophical way — of dealing with this question is to say that one knows what others are thinking etc. from analogy with one’s own case. Another way, however, is to go back to the Aristotelian conception of the soul as form of the body — which rules out radical scepticism about other people’s minds. In comparison with the Platonic story, at any rate, Aristotle’s view seems like plain common sense. On the other hand, the imaginative power of the Platonic story is so immense that liberation from it cannot be easily achieved. It is possible to read Wittgenstein’s Philosophical Investigations as an intervention in this long debate. By resorting to St Augustine’s picture of how (why) an infant acquires language, as he does at the beginning of the Investigations, isn’t Wittgenstein inviting his readers to learn to tell a different story about the soul from the one that is so entrenched in the Christian spiritual tradition?

Scepticism about our knowledge of other people’s minds, feelings, etc., may thus be met by the argument that one infers the existence of such hidden entities from analogy with one’s own case. But this concedes far too much to scepticism. This argument remains under the spell of the myth of the homunculus peeping suspiciously through the eyelet-holes of his face-mask at the surrounding horde of similarly masked creatures, all no doubt engaged in equivalent inferences. One alternative to this radically paranoid-solipsist conception is to return to the relatively ‘physicalist’ approach to be found in Aristotle (and perhaps, by qualified extrapolation, in Thomas Aquinas).