356 THE MISMEASURE OF MAN
Most biologists would follow my argument in denying a genetic
basis for most behavioral differences between groups and for change
in the complexity of human societies through the recent history of
our species. But what about the supposed constancies of personal-
ity and behavior, the traits of mind that humans share in all cul-
tures? What, in short, about a general "human nature"? Some
biologists would grant Darwinian processes a substantial role not
only in establishing long ago, but also in actively maintaining now,
a set of specific adaptive behaviors forming a biologically condi-
tioned "human nature." 1 believe that this old tradition of argu-
ment—which has found its most recent expression as "human
sociobiology"—is invalid not because biology is irrelevant and
human behavior only reflects a disembodied culture, but because
human biology suggests a different and less constraining role for
genetics in the analysis of human nature.
Sociobiology begins with a modern reading of what natural
selection is all about—differential reproductive success of individ-
uals. According to the Darwinian imperative, individuals are
selected to maximize the contribution of their own genes to future
generations, and that is all. (Darwinism is not a theory of progress,
increasing complexity, or evolved harmony for the good of species
or ecosystems.) Paradoxically (as it seems to many), altruism as well
as selfishness can be selected under this criterion—acts of kindness
may benefit individuals either because they establish bonds of
reciprocal obligation, or because they aid kin who carry copies of
the altruist's genes.
Human sociobiologists then survey our behaviors with this cri-
terion in mind. When they identify a behavior that seems to be
adaptive in helping an individual's genes along, they develop a
story for its origin by natural selection operating upon genetic var-
iation influencing the specific act itself. (These stories are rarely
backed by any evidence beyond the inference of adaptation.)
Human sociobiology is a theory for the origin and maintenance of
specific, adaptive behaviors by natural selection*; these behaviors must
*The brouhaha over sociobiology during the past few years was engendered by this
hard version of the argument—genetic proposals (based on an inference of adap-
tation) for specific human behaviors. Other evolutionists call themselves "sociobiol-
ogists," but reject this style of guesswork about specifics. If a sociobiologist is anyone