But for many people, taking a pill to sharpen your mental faculties – a so-called “cognitive enhancer” – is a much easier deal. A large number of prescription drugs can indeed give you a little mental boost, including amphetamine and methylphenidate (more familiarly known by its brand name Ritalin). Both the use and the range of such drugs are on the rise and they seem capable of stimulating debate just as readily as they do the brain.

They have their medical uses; as Ritalin, methylphenidate is used to treat attention deficit hyperactivity disorder (ADHD) and, less commonly, narcolepsy. Even this is not without controversy, but the fact that they seem to have the same enhancing effects in healthy people opens