A POSITIVE CONCLUSION 359
engendered controversy. The contentious subjects are specific
behaviors that distress us and that we struggle with difficulty to
change (or enjoy and fear to abandon): aggression, xenophobia,
male dominance, for example. Sociobiologists are not genetic
determinists in the old eugenical sense of postulating single genes
for such complex behaviors. All biologists know that there is no
gene "for" aggression, any more than for your lower-left wisdom
tooth. We all recognize that genetic influence can be spread dif-
fusely among many genes and that genes set limits to ranges; they
do not provide blueprints for exact replicas. In one sense, the
debate between sociobiologists and their critics is an argument
about the breadth of ranges. For sociobiologists, ranges are narrow
enough to program a specific behavior as the predictable result of
possessing certain genes. Critics argue that the ranges permitted
by these genetic factors are wide enough to include all behaviors
that sociobiologists atomize into distinct traits coded by separate
genes.
But in another sense, my dispute with human sociobiology is
not just a quantitative debate about the extent of ranges. It will not
be settled amicably at some golden midpoint, with critics admitting
more constraint, sociobiologists more slop. Advocates of narrow
and broad ranges do not simply occupy different positions on a
smooth continuum; they hold two qualitatively different theories
about the biological nature of human behavior. If ranges are nar-
row, then genes do code for specific traits and natural selection can
create and maintain individual items of behavior separately. If
ranges are characteristically broad, then selection may set some
deeply recessed generating rules; but specific behaviors are epi-
phenomena of the rules, not objects of Darwinian attention in their
own right.
I believe that human sociobiologists have made a fundamental
mistake in categories. They are seeking the genetic basis of human
behavior at the wrong level. They are searching among the specific
products of generating rules—Joe's homosexuality, Martha's fear
of strangers—while the rules themselves are the genetic deep struc-
tures of human behavior. For example, E. O. Wilson (1978, p. 99)
writes: "Are human beings innately aggressive? This is a favorite
question of college seminars and cocktail party conversations, and
one that raises emotion in political ideologues of all stripes. The