Assertion: reciprocal altruism | /r/CapableOf | spread in human society
Facets:
value: widely
type: DEGREE
Source sentences:
text: Some scholars, such as Michael Taylor, Anatol Rapoport, Robert Keohane, Arthur Stein, Helen Milner and Kennth Oye, point out that reciprocal altruism widely spread in international relations and human society, and international reciprocity is the foundation of the international community.