Darwin's Dangerous Idea - Evolution and the Meaning of Life

456 ON THE ORIGIN OF MORALITY
transfer, language. In Rawls' thought experiment about how a society ought
to be formed, we are to imagine a time, at the birth of society, when its
inhabitants gather to consider what sort of design their society shall have.
They are to reason together about this until they achieve what Rawls calls
"reflective equilibrium"—a stable agreement that cannot be upset by further
consideration. In this regard, Rawls' idea is like Maynard Smith's idea of an
evolutionarily stable strategy or ESS, but with a major difference: these are
people doing die calculation, not birds or pine trees or other simple
competitors in the games of life. The key innovation in Rawls' scenario, designed
to ensure that undue selfishness among the participants in this exercise
in reflection cancels itself out, is what he calls the "veil of ignorance."
Everyone gets to vote on a favored design of society, but when you decide
which society you would be happy to live in and give your allegiance to, you
vote without knowing what your particular role or niche in it will be. You
may be a senator or a surgeon or a street-sweeper or a soldier; you don't get
to find out until after you have voted. Choosing from behind the veil of ignorance
ensures that people will give due consideration to the likely effects,
the costs and benefits, for all the citizenry, including those worst off.
Rawls' theory has received, and deserved, more attention than any other
work in ethics in this century, and, as usual, I am presenting an oversimplified
version of the issues. My point is to draw attention to the placement of
this work, and all the work that it has provoked and inspired, relative to
Darwinian thinking in general, and "evolutionary ethics" in particular. Note
especially that, whereas Hobbes presented a rational reconstruction of
something that actually happened—something that must have happened—
Rawls presents a thought experiment about what, if it did happen, would be
right. Rawls' project is not speculative history or prehistory, but an entirely
normative project: an attempt to demonstrate how ethical questions ought to
be answered, and, more particularly, an attempt to justify a set of ethical
norms. Hobbes hoped to solve the normative problem about what ethics
ought to be—Rawls' problem—but, greedy reductionist that he was, he tried
to kill two birds with one stone: he also wanted to explain how such a thing
as right and wrong came into existence in the first place, an exercise of
imagination in the Darwinian mode. Needless to say, life is more complicated
than that, but it was a nice try.
Hobbes' account in the Leviathan has a fine Panglossian ring to it—in both
exapted senses of that popular word. First, by presupposing the rationality (or
Prudence, as he called it) of the agents whose mutual solution society is
supposed to be, he viewed the birth of society as dictated by reason, a forced
move, or at least strongly endorsed by reason, a Good Trick. In other words,
Hobbes' tale is an adaptationist Just So Story—and none the worse for it.
But, second, by appealing as it does to our sense of the good of our own
species, it is apt to lull us into overly sanguine models of how it must have
come about—and this is a serious criticism. It may occur to us
E Pluribus Unum? 457
that, however it came about, the birth of morality was a good thing for us,
but we should try not to indulge in that sort of reflection. No matter how true
it may be, it cannot explain how these practices, for which we are
retrospectively so grateful, came into existence and persisted. Group rationality
may not be assumed, any more than we may assume that since we
have benefited mightily from the eukaryotic revolution, it is thereby explained.
Group rationality, or cooperation, has to be achieved, and that is a
major design task, whether we are considering alliances of prokaryotes or
alliances of our more recent ancestors. In fact, much of the best work in
ethics in recent years has concerned precisely this issue (e.g., Parfit 1984,
Gauthier 1986, Gibbard 1985).
Before looking more closely at the human predicament in this regard, we
might consider more cautiously the metaphor that Hobbes invites us to take
seriously, helping ourselves to the improved perspective provided by the
Darwinian Revolution that has intervened. In what regards is a society like a
giant organism, and in what regards is it different?
Multicellular organisms have solved the problem of group solidarity. One
never hears tales of a person's thumbs rising up in civil war against the
neighboring fingers, or of an eagle's wings going on strike, refusing to work
unless some concession can be wrung from the beak or (more to the point)
the gonads. And now that we have the genes-eye perspective from which to
look at the world, this can strike us as something of a puzzle. Why don't
these rebellions happen? Each cell in a multicellular organism has its own
strings of DNA, a complete set of genes for making a whole organism, and if
genes are selfish, why do the genes in the thumb cells or wing cells so
docilely cooperate with the rest of the genes? Don't the DNA copies in the
thumbs and wings count as genes? (Are they denied the vote? Why do they
put up with it?) As the biologist David Sloan Wilson and the philosopher of
biology Elliot Sober (Wilson and Sober 1994) have suggested, we can learn
a lot about our social problems of defection (e.g., promising and then
reneging on the promise) and Hardin's tragedy of the commons (see chapter
9) by considering how our ancestors, going back to the first eukaryotes,
managed to achieve "harmony and coordination of their parts." The lessons
to be learned are tricky, however, because the cells that compose us belong
to two very different categories.
An average human is normally host to billions of symbiotic organisms
belonging to perhaps a thousand different species.... His phenotype is not
determined by his human genes alone but also by the genes of all the
symbionts he happens to be infected with. The symbiont species an individual
carries usually have a very varied provenance, with only a few being
likely to have come from his parents. [Delius 1991, p. 85.]
Am I an organism, or a community, or both? I am both—and more—but
there is a tremendous difference between the cells that are officially part of