Michael W Kraus, of the University of California, San Francisco, is one of a number of social psychologists who have recently been busy demonstrating that lower socioeconomic status (SES) is intricately linked to all sorts of prosocial behaviours. Everything else equal, the less wealth, education and employment status we have, the more charitable, generous, trusting and helpful we appear to become. In interactions with strangers, poorer people are more likely to use polite, attentive, respectful gestures. Most recently, in a paper just published in the prestigious journal Psychological Science, Kraus et al report that lower SES subjects show significantly greater empathy than their richer, better educated counterparts. He argues that this tendency to empathise may at least partly explain the other observations of prosocial behaviour.