 Wong has developed this approach at length in more recent work (2006). His “pluralistic relativism” continues to emphasize that there are universal constraints on what could be a true morality. The constraints are based on a naturalistic understanding of human nature and the circumstances of human life. For Wong, given a variety of human needs and the depth of self-interest, morality’s function is to promote both social co-operation and individual flourishing. In addition, morality requires that persons have both effective agency and effective identity, and these can only be fostered in personal contexts such as the family. Hence, the impersonal perspective must be limited by the personal perspective. Any true morality would have to respect requirements such as these.