Suppose I get an A and my pair gets a C, then sure I get that initial payoff of 3, but unfortunately I can't sleep at night because I'm feeling so guilty.

假如我得到A我对手得C,没错我开始得到3单位效用,但我感到愧疚,我因良心受到谴责

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Perhaps feeling guilty about neglect of their families, perhaps remembering their own indulged childhoods, today's parents are too soft on their children, say some social critics.

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In other words, one of the reasons we cooperate with others is to avoid feeling guilty.

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