can be sustained
if such individuals can accurately signal their
quality by making substantial
cooperative contributions to public goods.
For example millionaires
might donate an recreational or an art center
to their community.
Similarly, the same reputational
and sanctioning mechanisms
that can stabilize cooperation
can also sustain maladaptive practices
such as consuming the brains of dead relatives,
flattening the foreheads of infants,
or binding the feet of young girls.
There are actually a multitude of stable equilibria,
only some of which are cooperative.
The first, and perhaps the most intuitive,
is that rational, forwardlooking individuals
recognize the long-term payoffs
available at stable cooperative equilibria,
assume others are similarly sensible,
and choose the cooperative state.
The second approach is based
on the stochasticity inherent in any