An old, cynical adage holds that ‘if all you’ve got is a hammer, everything looks like a nail’. I remembered that aphorism while reading the new book by Simon Baron-Cohen, one of the world’s leading authorities on autism, in which he unpicks the instincts and processes that have driven human progress. His conclusion? The great engine of our advancement as a species has been autistic behaviour. It’s a bold, rather startling claim. In this intriguing volume, the author explains that it is the habitual pattern-seekers who are responsible for human invention. These are people who display what he calls ‘the Systemising Mechanism’, which developed in humans around 70,000-100,000 years ago.