In findings sure to gladden the heart of anyone who's ever wondered whether tiny acts of kindness have larger consequences, researchers have shown that generosity is contagious. Goodness spurs goodness, they found: A single act can influence dozens more. In a game where selfishness made more sense than cooperation, acts of giving were "tripled over the course of the experiment by other subjects who are directly or indirectly influenced to contribute more," wrote political scientist James Fowler of UC San Diego, and medical sociologist Nicholas Christakis of Harvard. Their findings, published March 8 in the Proceedings of the National Academy of Sciences, are the latest in a series of studies on the spread of behaviors through social networks.
