The brain

Given the ingenuity of machine-makers, said Descartes in the 17th century, machines might well be constructed that exactly resemble humans. There would always, however, be ‘a reliable test’ to distinguish them. ‘Even the stupidest man’ is equipped by reason to adapt to ‘all the contingencies of life’, while no machine could ever be made with enough pre-set ‘arrangements’ to be convincingly versatile. But suppose it could? In 1950 Alan Turing proposed a test remarkably similar to Descartes’s. A computer and a human are asked questions, each being invisible to the questioner, and their respective responses compared. If the computer’s can be mistaken for the human’s, displaying equivalent versatility and apparent

The dust jacket of The Matter With Things quotes a large statement from an Oxford professor: ‘This is one of the most important books ever published. And, yes, I do mean ever.’ Can any contemporary work withstand such praise? The ‘intelligent general reader’ (the book’s target audience) should, however, not be discouraged, for Iain McGilchrist has to be taken seriously: a Fellow of All Souls, eminent in neurology, psychiatry and literary criticism, a thinker and — it’s impossible to avoid the term —a sage. His previous book, The Master and His Emissary, was admired by public figures from Rowan Williams to Philip Pullman. Some consider McGilchrist the most important non-fiction

Jesus is a Malteser. You might say I’m a liar or accuse me of the most egregious heresy, but the fact remains that Jesus is a Malteser. This is because I have a neurological quirk known as synaesthesia, commonly described as a fusing of the senses. Its most common manifestation prompts people to see colour when they hear music. But my version is the rare lexical-gustatory kind, which means that I can taste words; and so Jesus is a Malteser, Sam is tinned tuna and Donald is a rubber duck bobbing around in vinegar. This could seem nightmarish: life as a constant assault of rubber ducks and whiffy fish —