An old and recurring theme in human relationships, jealousy has been captured in myth, drama, literature, dance, sculpture, and painting, as well as in the popular press. Jealousy is also a major cause of murder, spousal violence, and marital breakdown. It has been estimated that up to 20% of all murders involve a jealous lover, and, in a nation-wide survey of marriage counselors, jealousy was cited as a (if not the) major focus of treatment for about...