1. The Moral Judgement of the Child;Piaget,1965
2. Stage and sequence: the cognitive-developmental approach to socialization;Kohlberg,1969
3. The evolution of reciprocal altruism;Trivers;Q. Rev. Biol.,1971
4. How the Mind Works;Pinker,1997
5. ‘Any animal whatever’: Darwinian building blocks of morality in monkeys and apes;Flack,2000