The ethologically oriented method of social analysis developed by Edward Westermarck is applied to the subjects of charitable behavior, the welfare ethic, and the link between them. Westermarck dealt with these topics, but not in the depth he accorded the subjects of incest aversion, the incest prohibition, and the connection between them. Westermarck's approach to analyzing incest behavior and regulating institutions is also useful in the case of charitableness and the welfare ethic. Westermarck would have analyzed the welfare ethic as an institution derived from human nature--secundam naturam--in addition to an authoritative discipliner of behavior as proposed by Freud. Evidence is presented that this is the case with the welfare ethic in modern societies. This evidence includes the sensitivity of welfare to ethnic diversity. The latter decreases public altruism, whether expressed as charitableness to beggars, national charities, or public goods. The parochial leaning of charity and the welfare ethic is allowed for by Westermarck's empirically grounded ethics. Despite the passage of nearly a century, Edward Westermarck can still be an instructive guide to the biosociological enterprise. This continuing relevance shows what could have been, and can still be, done with the conceptual tools offered by an evolutionarily informed sociology.