With scientists mapping our neurons in ever greater detail, and programmers creating ever more humanlike artificial intelligence, the gap between brain and machine seems to be rapidly shrinking — throwing the question of consciousness, one of the great philosophical mysteries, back into the heart of scientific debate. Will the human mind — that ineffable tangle of private, first-person experiences — soon be shown to have a purely physical explanation? The neuroscientist Steven Novella certainly thinks so:

‘The evidence for the brain as the sole cause of the mind is, in my opinion, overwhelming.