There is actually a human algorithm in the cooperate/defect space—which is to distrust anyone who seems to spend a long time making a cooperate decision. Anyone who has a really quick, simple way of deciding to cooperate is OK—anyone who takes a long time is thinking about whether you will defect, or whether they should defect—and you should probably find someone else to trust. This is one of the good things about Tit for tat—it passes this test.
There is actually a human algorithm in the cooperate/defect space—which is to distrust anyone who seems to spend a long time making a cooperate decision. Anyone who has a really quick, simple way of deciding to cooperate is OK—anyone who takes a long time is thinking about whether you will defect, or whether they should defect—and you should probably find someone else to trust. This is one of the good things about Tit for tat—it passes this test.