Like many members of the animal kingdom, people will readily lend a hand to immediate family and relatives. But humans alone extend altruism beyond kin, frequently helping perfect strangers for no obvious personal gain. Whether we live in large or small groups, in the global network of the New Economy or in the most isolated Yanomami reservation along the border between Venezuela and Brazil, human cooperation in the absence of family ties is widespread across cultures.
On what is this largehearted behavior built? Does each of us possess an inner samaritan who is selfless and community-minded, as philosophers have sometimes proposed? Or--as many sociobiologists have suggested--are actions that are seemingly done for the benefit of others really motivated by veiled economic calculations and selfishness or by egoism, with an eye to the very long term?
This article was originally published with the title The Samaritan Paradox.