The arrangement of features in the human face largely reflects sensory, dietary and linguistic considerations, so all faces look more or less the same. This means that minor variations can effectively convey social signals and information about identity. This is why natural facial disfigurements have such a profound effect on people's lives. It also explains the disturbing effect of artistic violations of the face, such as this striking painting, Le Viol (The Rape) by René Magritte. Or so argue Vicki Bruce and Andy Young in In the Eye of the Beholder: The Science of Face Perception (Oxford University Press, £25). They bring together science and art to explain the importance of the face, how we extract the information it contains, and reveal what it all means