From Sam Edge, Ringwood, Hampshire, UK
I enjoyed David Robson’s advice to the reader who worried about being gullible. He is right to point out that we are generally unable to tell if someone is lying in casual conversation. The reader might also be reassured by research showing that even those whom we might expect to be better at this, like law enforcement personnel, are equally hopeless even after supposedly science-based interrogation training. Operators of the non-scientific “lie detector”, or polygraph, test have also been shown to be mistaken – with both false positives and false negatives – so often as to make their conclusions virtually worthless(10 May, p 43).
