I think it is best if we look at these issues in terms of human psychology and how it is important for political philosophy.<p>In order to decide what is the best society, we need to know what is good for human beings, and this depends in part on human psychology. Furthermore in order to have such a good society, we need to get people to behave well, and in order to decide how to most effectively attempt to do that we need to understand why people behave in good or bad ways, and again this depends in part on human psychology.<p>The question then is what is human psychology, including what is universal about it and in what ways it varies, as from person to person or culture to culture, all as relevant to the questions of what is good for human beings and why they behave as they do, good or bad.<p>These are complicated matters, but I think they are considerably answered by looking at basic human needs, such as Maslow's need theory, and also basic human cognitive abilities.