Tom Stafford and Matt Webb were at Foyles on Charing Cross Road (London) on Wednesday night to publicize their book Mind Hacks (O’Reilly). They stepped through a few practical examples of the stuff from the book — why faded jeans make your legs look good; how eyes and the brain adapt to light and noise levels; why putting a pen in your mouth and pushing it back for three minutes makes you feel good — fairly successfully and made some jokes about leopards.