THE CHALLENGE OF EVOLUTIONARY ETHICS little practical cost. In a hostile environment, those small tribal groups populated by altruists and co-operators would have a decided advantage. Cheating would not likely become wide spread, since the advantage would be quite small and the possible cost quite high (e.g., ostracism of the individual or death of the tribe). Under such circumstances group selection, especially on tribes laced with relatives, might well become a force to install virtuous behavior. For an analysis of the problematic assumptions of most group selection models, see Wade (1978). 3 This is largely the objection of Marshall Sahlins to the sociobiology of human behavior (1976). 4 Playing on the apparent reduction of altruistic behavior to genetic selfishness and then to selfishness simply, Lewontin et al. complain: 'by emphasizing that even altruism is the consequence of selection for reproductive selfishness, the general validity of individual selfishness in behaviors is supported ... Sociobiology is yet another attempt to put a natural scientific foundation under Adam Smith" (1984, p. 264). 5 In an early discussion of evolutionary ethics, Ruse (1979, pp. 199-204) affirmed that any evolutionary ethics must commit the naturalist fallacy, and admitted that the two characteristics mentioned in the text produce the most potent objections to evolutionary ethics: without begging the question, we would have no way of specifying what trends or what aspects of the evolutionary process should constitute the moral standard. ' For a consideration of inference principles of the kind mentioned, see Carnap (1956, pp. 222-32), Sellars (1948), and McCawlcy (1981, p. 46). 7 Gewirth (1982, pp. 82-3) endorses the following criteria as establishing a motive as moral: the agent takes it as prescriptive; he universalizes it; he regards it as over-riding and authoritative; and it is formed of principles that denominate actions right simply because of their effect on other persons. These criteria are certainly met in altruistic behavior described by RV.
What is "evolutionary ethics"? A quick answer might be: it is the type of ethics put forward by E. O. Wilson in On Human Nature. Richards' proposal, which attempts to review and complete this ethics, is obviously construed in this way. But I shoud like to delve further into what is meant by "the ethics in On Human Nature". Let us turn to what is probably the most meaningful chapter on the subject, chapter VII, which deals with