A monthly e-column by Massimo Pigliucci
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 else’s wealth) regularly
make the bestsellers list.
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.
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.
also tried to establish ethics on firm rational foundations, in his case
improving on Jeremy Bentham’s 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 one’s own.
got worse with the advent of modern evolutionary biology. It seemed for a long
time that Darwin’s 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.
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.
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.
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 don’t appreciate the math behind the
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 proposer’s reputation for the next round. This means that—given
the social environment—it is rational to be less selfish toward your
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?"
Stuart Mill on the Internet
Encyclopedia of Philosophy
by Plato, complete text online
theory and evolutionarily stable strategies, an interactive website
Skeptic & Humanist Web