Today, let's help the prisoner sort out his
dilemma. The University of Houston's College of
Engineering presents this series about the machines
that make our civilization run, and the people
whose ingenuity created them.
Scholars invent a shorthand
for the great problems of human behavior. They talk
about Hobson's Choice, Occam's Razor, and Gresham's
Law. One of the most disturbing of these conundrums
is the Prisoner's Dilemma.
Two prisoners have committed a crime. Now they're
held in separate cells. Each can either confess and
plead for a light sentence or claim innocence and
blame the other.
If one blames and one confesses, the blamer fares
well and the confessor suffers. If each blames the
other, it goes hard for both. In aggregate, they do
best when each confesses.
Now: You and I are those prisoners. Oh, we may not
be in jail, but the same moral dilemma comes up all
the time in everyday life. I think of times I've
seen two students turn in identical tests. How do
people really behave in such moments?
The Prisoner's Dilemma is mired in questions of
honesty and compassion -- as well as self-interest.
And remember: Most participants have to deal with
each other afterward. Since the pair does best when
both confess, the Dilemma blurs the line between
the best interests of the individual and of
Philosophers, psychologists, and mathematicians
have all wrestled with implications of the
Prisoner's Dilemma. Now computer modelers and
animal behaviorists are in the act. They set up a
dizzying array of games, tests, and simulations to
see how both people and animals react to such a
Those experiments make some things clear. The
long-range behavior in society is imitative. You
imitate what works. You go for cooperation. You
confess. But when you do, you lay society open to
the one person who exploits things to his own
advantage. He poses a terrible threat to
cooperative behavior. Both animal populations and
computer models for human behavior show that we'd
better punish him. If we don't, we're in trouble.
If you let me get away with condemning you, while
you confess, then you undermine the learning that
sustains cooperative behavior. The computers say
that if you let me blame you twice, you get what
you deserve the second time. In that sense, I hold
society together by keeping you alert to my evil.
Still, the computers cannot capture all the
dimensions of human behavior. They don't account
for backbiting and vendetta. Anger can lead people
to seek revenge and damn the personal cost. But we
also transcend simple tests with the power of
We violate simple cause and effect. We defy the
calculus of behavior. We negate that logic in the
very act of letting the Prisoner's Dilemma touch
our conscience -- and disturb our sleep.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds