Robert Trivers makes another significant contribution to evolutionary and behavioural biology in his latest book about deceit and self-deception (Nature 478, 314–315; 2011).

The idea that self-deception is beneficial because it makes it easier to deceive others has also been noted by other observers of human nature. Writer Mark Twain declared: “When a person cannot deceive himself, the chances are against his being able to deceive other people,” and author Elizabeth Bear more recently advised: “The secret to getting away with lying is believing with all your heart.”