Further reading:

A
Darwinian Left: Politics, Evolution, and Cooperation
by Peter Singer |
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Is it rational to be ethical? Many
philosophers have wrestled with this most fundamental of questions, attempting to clarify
whether humans are well served by ethical rules or whether they weigh us down. Would we
really be better off if we all gave in to the desire to just watch out for our own
interests and take the greatest advantage to ourselves whenever we can? Ayn Rand, for one,
thought that the only rational behavior is egoism, and books aiming at increasing personal
wealth (presumably at the expense of someone elses wealth) regularly make the
bestsellers list.
Plato, Kant,
and John Stuart Mill, to mention a few, have tried to show that there is more to life than
selfishness. In the Republic, Plato has Socrates defending his philosophy against
the claim that justice and fairness are only whatever rich and powerful people decide they
are. But the arguments of his opponents that we can see plenty of examples of
unjust people who have a great life and of just ones who suffer in equally great manner
seem more convincing than the high-mindedness of the father of philosophy.
Kant
attempted to reject what he saw as the nihilistic attitude of Christianity, where you are
good now because you will get an infinite payoff later, and to establish independent
rational foundations for morality. Therefore he suggested that in order to decide if
something is ethical or not one has to ask what would happen if everybody were adopting
the same behavior. However, Kant never explained why his version of rational ethics is
indeed rational. Rand would object that establishing double standards, one for yourself
and one for the rest of the universe, makes perfect sense.
Mill also
tried to establish ethics on firm rational foundations, in his case improving on Jeremy
Benthams idea of utilitarianism. In chapter two of his book Utilitarianism,
Mill writes: Actions are right in proportion as they tend to promote happiness;
wrong as they tend to produce the reverse of happiness. Leaving aside the thorny
question of what happiness is and the difficulty of actually making such calculations, one
still has to answer the fundamental question of why one should care about increasing the
average degree of happiness instead of just ones own.
Things got
worse with the advent of modern evolutionary biology. It seemed for a long time that
Darwins theory would provide the naturalistic basis for the ultimate selfish
universe: nature red in tooth and claw evokes images of every man for himself,
in pure Randian style. In fact, Herbert Spencer popularized the infamous doctrine of
Social Darwinism (which Darwin never espoused) well before Ayn Rand wrote Atlas
Shrugged.
Recently,
however, several scientists and philosophers have been taking a second look at
evolutionary theory and its relationship with ethics, and are finding new ways of
realizing the project of Plato, Kant, and Mill of deriving a fundamentally rational way of
being ethical. Elliot Sober and David Sloan Wilson, in their Unto Others: the
Psychology and Evolution of Unselfish Behavior, as well as Peter Singer in A
Darwinian Left: Politics, Evolution and Cooperation, argue that human beings evolved
as social animals, not as lone, self-reliant brutes. In a society, cooperative behavior
(or at least, a balance between cooperation and selfishness) will be selected in favor,
while looking out exclusively for number one will be ostracized because it reduces the
fitness of most individuals and of the group as a whole.
All of this
sounds good, but does it actually work? A recent study published in Science by
Martin Nowak, Karen Page and Karl Sigmund provides a splendid example of how mathematical
evolutionary theory can be applied to ethics, and how in fact social evolution favors fair
and cooperative behavior. Nowak and coworkers tackled the problem posed by the so-called
ultimatum game. In it, two players are offered the possibility of winning a
pot of money, but they have to agree on how to divide it. One of the players, the
proposer, makes an offer of a split ($90 for me, $10 for you, for example) to the other
player; the other player, the responder, has the option of accepting or rejecting. If she
rejects, the game is over and neither of them gets any money.
It is easy
to demonstrate that the rational strategy is for the proposer to behave egotistically and
to suggest a highly uneven split in which she takes most of the money, and for the
responder to accept. The alternative is that neither of them gets anything. However, when
real human beings from a variety of cultures and using a panoply of rewards play the game
the outcome is invariably a fair share of the prize. This would seem prima facie evidence
that the human sense of fair play overwhelms mere rationality and thwarts the
rationalistic prediction. On the other hand, it would also provide Ayn Rand with an
argument that most humans are simply stupid, because they dont appreciate the math
behind the game.
Nowak and
colleagues, however, simulated the evolution of the game in a situation in which several
players get to interact repeatedly. That is, they considered a social situation rather
than isolated encounters. If the players have memory of previous encounters (i.e., each
player builds a reputation in the group), then the winning strategy is to be
fair because people are willing to punish dishonest proposers, which increases their own
reputation for fairness and damages the proposers reputation for the next round.
This means that given the social environment it is rational to be
less selfish toward your neighbors.
While we are
certainly far from a satisfying mathematical and evolutionary theory of morality, it seems
that science does, after all, have something to say about optimal ethical rules. And the
emerging picture is one of fairness not egotism as the smart choice to make.
Next Month: "Red
or Blue? What kind of life would you choose?"
© by Massimo Pigliucci, 2001
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