Thinking and Deciding

462 SOCIAL DILEMMAS: COOPERATION VERSUS DEFECTION
which option would make more money for the decision maker. In other words, those
subjects who showed a greater parochialism effect for contributing showed a greater
self-interest illusion when the gain for their group was a loss for the other group.
When subjects were forced to calculate the effects of their contribution on themselves
and others, the parochialism effect was reduced. Thus, parochialism is somewhat
labile. It may be possible, through reason, to understand the arbitrariness of
group boundaries. The more that people think of boundaries as arbitrary, the more
they can direct their non-self-interested concern at the greater good rather than the
parochial interests of their group.
Solutions to social dilemmas
By definition, cooperation is better for all, so it is something that we would want to
increase in general. First, it is clear that there is much we can do to maintain moral
norms that favor it. We can encourage thoughtfulness and altruism. Moreover, we
can discourage some of the motives that work against cooperation and that have little
useful purpose, such as competition and envy, when these motivate harm to others or
failure to cooperate.
Fear and greed, as we have defined them, are more complex. The goodness or
badness of each may depend on the situation. In some situations, cooperation is
most beneficial when few others are cooperating. An example is calling attention
to a hazard. In these situations, “greed” is harmless. But fear amounts to keeping
your mouth shut just because everyone else is doing the same. In other situations,
cooperation is most helpful when many others are cooperating, such as when the
goal is to keep a secret. Here, greed is insidious, but fear is harmless. Perhaps people
can learn to adapt their motives — or at least their behavior — to the situation.
What seems most interesting is the common tendency to rely on the behavior of
others as a guide. We cooperate when we think others are cooperating, and defect
when we think they are defecting. This happens, I have argued, for several reasons:
conformity, communication of social norms, fear (of being a sucker), the desire for
fairness, and retaliation for defections. Very often, however, the benefit of cooperation
for others, and the cost for ourselves, does not depend at all on the number of
other cooperators. Thus, cooperation is particularly lacking when people think that
few others are cooperating.
We can rely only so much on changes in human motives and habits. When selfinterest
is too strong, other solutions to social dilemmas must be considered. It is not
clear, for example, that altruistic concern for the growth of world population has had
any noticeable effect on decisions about childbearing in any countries.
Experimental approaches
Several experimental results provide suggestions about what does and does not affect
cooperation.