The Desire for Sexual Identity--One of the "Very Widespread Regularities" of Human Nature

When I first began studying political philosophy in the late 1960s as an undergraduate student at the University of Dallas, it seemed to me that political philosophy was the study of human nature as universal human propensities diversely expressed in the variable historical circumstances of human individuals and human societies. 

In 1975, as a graduate student at the University of Chicago, I first saw Ed Wilson's Sociobiology on the new book table at the Seminary Coop Bookstore.  I remember thinking, as I skimmed over his last chapter on human sociobiology, that a Darwinian science of human nature could illuminate and adjudicate debates over human nature in the history of political philosophy.  In 1978, a conference paper by Roger Masters persuaded me that a science of evolved human nature could support a new understanding of Aristotelian natural right.  In the 1980s and early 1990s, I saw the writing about evolutionary psychology coming from Leda Cosmides, John Tooby, and others as contributing to this new science of human nature that could sustain what I called "Darwinian natural right."

Sometime around 1986, I met David Hull, a philosopher specializing in the philosophy of biology.  When I spoke to him about my interest in applying a biology of human nature to political philosophy, he warned me that evolutionary biology would not support any conception of human nature, if that was understood as some unchanging human essence.  Darwinian science denied such "essentialist" thinking, he explained, by showing that all living beings--including human beings--are historically contingent and variable, and therefore there is no enduring human nature and no enduring moral or political standard for judging human life rooted in human evolution.  Later, I discovered that one of my colleagues at Northern Illinois University--David Buller--had studied under Hull at Northwestern University, and that Buller's dissertation had elaborated Hull's argument against a biological human nature as assumed by evolutionary psychology.  In 2005, Buller's dissertation was published as a book--Adapting Minds: Evolutionary Psychology and the Persistent Quest for Human Nature. 

As the title indicates, Buller was responding to Cosmides and Tooby's edited volume--The Adapted Mind: Evolutionary Psychology and the Generation of Culture.  "The Adapted Mind" might suggest a single mind fixed by evolutionary adaptation for all human beings, which would constitute a universal human nature.  "Adapting Minds" suggests multiple minds that are changing in response to changing circumstances, which would mean that there is no enduring human nature produced by evolution.  Indeed, Buller declares his agreement with Michael Ghiselin's claim that "human nature is a superstition."

As I have indicated in a previous post, I agree with Buller that the evolutionary psychologists sometimes seem to stress the uniformity of human nature in such a way as to ignore the individual diversity that manifests the psychological polymorphism that has emerged from evolutionary history.  I also agree with him that in claiming that we all today have a "Stone Age mind" adapted to the environment of Pleistocene hunter-gatherers, the evolutionary psychologists can seem to mistakenly assume that there has been no human evolution over the past 10,000 years.

But on the most crucial point--the very idea of human nature--I am on the side of the evolutionary psychologists.  If one defines human nature in a silly way (as Buller and Hull do), then human nature does not exist.  But if one defines human nature in a sensible way, then human nature surely does exist.

Buller's silly definition of human nature is that it would have to consist only of traits that satisfy three conditions--first, they must be unique to human beings and thus not shared with any other animals; second, they must be invariably and exactly the same for all human individuals everywhere; and, third, they must be eternal essences that are not historically contingent.  It is easy for Buller to argue that human evolution has not produced a human species with such traits.

But a sensible definition of human nature does not require these conditions.  We can define human nature as constituted by that suite of generally recurrent anatomical, physiological, and psychological traits that characterize the human species.  Buller implicitly concedes this sensible definition of human nature when he speaks of human anatomy, human physiology, and human psychology as realities that can be scientifically studied.  Buller says that "psychology may one day provide us with descriptions of some very widespread regularities among the minds of our conspecifics" (456).  Well, then, if we define human nature as constituted by "very widespread regularities" among human beings in their minds and bodies, then human nature exists.

Among those "very widespread regularities," I include the twenty natural desires that constitute the motivational basis for moral and political psychology.  Because of the variability in those desires and in the circumstances of action across individuals and across societies, we need prudence or practical judgment in deciding what is best for particular individuals in particular circumstances.  But the regularity in the human nature of those desires sets some general standards for moral and political judgment.

Consider, for example, the natural desire for sexual identity.  Human beings generally desire to identify themselves as male or female. Sex is the single most important characteristic of personal identity.  It is the first question we ask about a newborn infant.  It is the first thing we notice about a person and the last thing we forget.  In all human societies, sex terminology is fundamentally dualistic.  Male and female are the basic sexes.  Others are either a combination of the basic sexes (hermaphrodites) or a crossover from one to the other (men who act as women or women who act as men).  All human societies have some sexual division of labor.  And although different societies assign somewhat different sex roles, thee are some recurrent differences that manifest a universal bipolarity in the pattern of human desires.  For instance, women in general (on average) tend to be more nurturing as manifested in a greater propensity to care for children, and men in general (on average) tend to be more aggressive as manifested in a greater propensity to violence.  Yet while these average differences are true for most men and women, for some individuals it is not: some women have manly desires, and some men have womanly desires.

Sanderson might say that I am confusing sex with gender.  Sex refers to the biological differences in anatomy and physiology between males and females.  Gender refers to the social roles of boys and men, on the one hand, and girls and women, on the other hand.  Moreover, Sanderson claims that while nonhuman animals show the sexual differences between male and female, only humans have gender.  And yet while Sanderson sees gender as different from sex, he does not see it as detached from sex.  Biological sex constrains but does not determine cultural gender.

The links between sex and gender are manifest in the universals of gender differences shaped by human evolution.  Sanderson surveys the evidence for at least six universals that we can identify as "very widespread regularities" of human nature.

(1) "Everywhere men display more aggressiveness."
(2) "Everywhere men are more competitive."
(3) "Everywhere men monopolize political leadership."
(4) "Everywhere women do the majority of the parenting."
(5) "Everywhere men and women display different kinds of cognitive skills."
(6) "Everywhere men and women have a strong sense of gender identity."

(1) Everywhere men on average are more aggressive than women, in the sense of a stronger propensity to physical violence.  As reviewed by John Archer and others, hundreds of studies using a wide variety of methodologies have shown in all societies greater aggressiveness on average for boys and men than for girls and women.

As is true for all six universals in gender, Sanderson (like me) stresses that the difference here is on average, which recognizes that some individuals depart from the average pattern.  Some women are more aggressive than some men.  Girls with above average levels of testosterone are more aggressive than girls with average levels of testosterone.  On average, most men have higher levels of testosterone than most women, but this is not true for all individuals.

The average gender difference in aggressiveness is connected through evolutionary adaptation to differences in bodily size and strength.  On average, men are taller, heavier, stronger, and more muscular than women.

Because of this difference in aggressiveness, war has always been an almost exclusively male activity.  The recent decision of the U.S. Department of Defense to open combat positions to women is a fascinating experiment.  Very aggressive women will be attracted to do this.  It is a safe prediction, however, that war will never be a predominantly female activity.

(2) Everywhere men are on average more competitive than women, in that men are more inclined to fight for high status and resources.  In every human society, there tends to be more men than women in the positions of highest status.  The best explanation for this is sexual selection: in evolutionary history, men have competed with other men for access to the resources necessary to attract high-quality mates, and women tend to prefer men with resources and high status.

(3) Everywhere the highest positions of political leadership are held predominantly by men.  Even in foraging bands, where there are no formal positions of political leadership, there is some informal leadership by men.  There is no clear evidence that any society has ever been a matriarchy, in which women hold all or most of the highest positions of leadership.

In modern industrial societies, the legislative, executive, and judicial branches of government are largely male dominated.  In recent decades, a growing number of women have entered the political realm.  The Scandinavian countries have an average of about 40 percent of the parliamentary seats filled by women.  As heads of state (presidents or prime ministers), men hold 95 percent or more of these positions around the world.

But, again, many individual women show high political ambition.  A Margaret Thatcher or a Hillary Clinton shows the ambition of high-testosterone women.

(4) Among many animals, males contribute little or no parental care for offspring.  Human fathers generally contribute more to parental care than is characteristic of over animals.  Even so, fathers on average contribute much less to parenting than do mothers.

This manifests the sexual division of labor in which women tend to engage in those activities that are compatible with extensive care for their children, while men on average have more freedom to enter roles that take them away from extensive parental care.

(5) There is plenty of evidence that all of the sex differences in motivation between men and women are connected to differences in their cognitive skills.  Mental testing shows that women on average are better than men in verbal ability, remembering the location of objects, and in reading facial expressions, while men on average are better in spatial ability, mental rotation of objects, maze running, and route finding.  These differences are magnified at puberty when testosterone levels increase in males.  These differences have been found among foraging bands and in some other mammalian animals.

There are two theories to explain the evolution of these sex differences in cognitive skills.  According to the sexual selection theory, males need good spatial skills to navigate large territories in searching for mates, which would be true especially for polygynous species, where males have larger navigational ranges than females.  According to the hunter-gatherer theory, the sex differences arise from the sexual division of labor, so that the cognitive skills necessary for hunting animals have evolved more prominently among males, and the cognitive skills necessary for gathering plants have evolved more prominently among females.  There is some evidence for both theories.

(6) In all human societies, men and women have a strong sense of their identity as male or female.  There is some evidence that this is correlated with differing prenatal levels of testosterone.  So that women who had high prenatal levels of testosterone during their development in the uterus are more masculine in their gender role identity.  Since men usually have had much higher levels of prenatal testosterone than women, this would partially explain why they generally have a more highly masculine identity in contrast to the more feminine identity of women.

All of this suggests that, as Sanderson says, "a completely degendered society is not possible" (225).  And thus we should expect that experiments in completely abolishing gender identity and creating androgynous societies will fail.

If sexual identity were a purely social construction, as many social scientists have assumed, then, as Sanderson indicates, we would have to make two kinds of predictions.  First, we would have to predict that the patterns of gender identity vary arbitrarily and randomly across societies, so that we would see the entire range of possible variation.  We might expect that in about one-third of societies, women would be more aggressively violent than men, and men would be the primary caregivers for infants and children.  In another one-third of societies, we might expect to see no sex differences at all in these traits, And, finally, in another one-third of societies, we would expect to see the pattern that is most familiar to us--men being more aggressive than women, and women being more inclined to child-care than are men.  But this prediction of totally arbitrary and random variation is not what we see.

The second prediction of the social construction theory is that those people who are born as genetic males could be successfully reared to have a female gender identity, and those who are born as genetic females could be successfully reared to have a male gender identity.  This experiment has been tried and failed.  The most famous case is that of the Canadian Bruce/Brenda/David Reimer.  This was the boy whose infant circumcision was so badly botched that he was castrated.  His parents were advised by John Money to remove the baby's testicles and rear him as a girl.  He predicted that socialization as a girl could turn Bruce into Brenda.  And for many years, psychology textbooks reported this as proof that gender identity was purely a social construction.  But Brenda never felt like a girl, and she was tormented by this.  When her parents finally revealed to her as a teenager what they had done, she insisted on turning herself back into a boy--David Reimer.  But David remained tormented by the effects of what he had suffered, and finally he committed suicide.

And yet, of course, gender identity is to some degree socially constructed, in that some patriarchal societies try to magnify the differences between the sexes in ways that allow men to totally dominate women, while other more egalitarian societies try to minimize the differences so that women have some freedom of opportunity to chose how they live, and to attain a social status equal to men.  In modern liberal societies, with gender equality of opportunity, there isn't much difference in the way  boys and girls are socialized, and as a result, sex differences are not a pronounced as they are in patriarchal societies. 

In such liberal societies, men and women are free to satisfy their natural desire for sexual identity and all their other natural desires in ways that conform to their individual propensities and abilities.  That's why liberal societies can be judged superior to illiberal societies, because liberal societies are more compatible with human nature.

Other posts on sexual identity and the debate over whether human nature includes more than two sexes can be found here, here, here, here, here, and here.