In Adaptation and Natural Selection, Williams said that when doing favors there should be no motive involved (Wright 1994). It is necessary for the help that you provide due others to sometimes be returned if the whole process is to be favored by natural selection, and the giver or the receiver does not need to be aware of this. The person that takes full advantage of their friendship and minimizes their aggression will have an advantage evolutionary wise (Wright 1994). The selection should favor the people that promote the good personal relationships. Williams's basic point is one that we have heard before. Animals and people often use evolutionary logic not really thinking about it, but just going by their feelings. Williams suggested that these feelings may include compassion and gratitude. Gratitude is what can get people to repay favors without giving much thought to what they are doing. But if compassion is stronger feeling for some people then it could leave us unaware of the fact to repay kindness (Wright 1994).
Williams's ideas were put into one big theory by Robert Trivers. In 1971, one hundred years after Darwin's ideas on reciprocal altruism were in The Descent of Man, Trivers published a paper that was called "The Evolution of Reciprocal Altruism" In The Quarterly Review of Biology (Wright 1994). In the paper's abstract he talked about how friendship, dislike, moralistic aggression, gratitude, sympathy, trust, suspicion, trustworthiness, aspects of guilt, and some forms of dishonesty and being hypocrites can be important adjustments to keep altruism in control (Wright 1994). .
Game Theory.
Game Theory was developed in the 1920's and thirties as a way to study decision making. Game theorists manage to make the study of human behavior neat and clean, but do pay a high price in realism (Wright 1994). They assume that what people do in life can be summarized in a single psychological phrase such as pleasure, happiness, or utility.