Back of the Envelope

This is an old but interesting article (hat tip to Mark Steyn in the Corner), although not everyone may like its conclusion:

Throughout the broad sweep of human history, there are many examples of people, or classes of people, who chose to avoid the costs of parenthood. Indeed, falling fertility is a recurring tendency of human civilization. Why then did humans not become extinct long ago? The short answer is patriarchy.

Patriarchy does not simply mean that men rule. Indeed, it is a particular value system that not only requires men to marry but to marry a woman of proper station. It competes with many other male visions of the good life, and for that reason alone is prone to come in cycles. Yet before it degenerates, it is a cultural regime that serves to keep birthrates high among the affluent, while also maximizing parents' investments in their children. No advanced civilization has yet learned how to endure without it.

Through a process of cultural evolution, societies that adopted this particular social system -- which involves far more than simple male domination -- maximized their population and therefore their power, whereas those that didn't were either overrun or absorbed. This cycle in human history may be obnoxious to the enlightened, but it is set to make a comeback.

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Patriarchal societies come in many varieties and evolve through different stages. What they have in common are customs and attitudes that collectively serve to maximize fertility and parental investment in the next generation. Of these, among the most important is the stigmatization of "illegitimate" children. One measure of the degree to which patriarchy has diminished in advanced societies is the growing acceptance of out-of-wedlock births, which have now become the norm in Scandinavian countries, for example.

Under patriarchy, "bastards" and single mothers cannot be tolerated because they undermine male investment in the next generation. Illegitimate children do not take their fathers' name, and so their fathers, even if known, tend not to take any responsibility for them. By contrast, "legitimate" children become a source of either honor or shame to their fathers and the family line. The notion that legitimate children belong to their fathers' family, and not to their mothers', which has no basis in biology, gives many men powerful emotional reasons to want children, and to want their children to succeed in passing on their legacy. Patriarchy also leads men to keep having children until they produce at least one son.

Another key to patriarchy's evolutionary advantage is the way it penalizes women who do not marry and have children. Just decades ago in the English-speaking world, such women were referred to, even by their own mothers, as spinsters or old maids, to be pitied for their barrenness or condemned for their selfishness. Patriarchy made the incentive of taking a husband and becoming a full-time mother very high because it offered women few desirable alternatives.

To be sure, a society organized on such principles may well degenerate over time into misogyny, and eventually sterility, as occurred in both ancient Greece and Rome. In more recent times, the patriarchal family has also proved vulnerable to the rise of capitalism, which profits from the diversion of female labor from the house to the workplace. But as long as the patriarchal system avoids succumbing to these threats, it will produce a greater quantity of children, and arguably children of higher quality, than do societies organized by other principles, which is all that evolution cares about.

As you see, the basic idea is that the patriarchy, defined as the societal model where children are seen as part of the father's family, is the most successful when it comes to producing a large number of children. There are several reasons for this. The first is that this gives men an incentive to invest in their children, and frowns on illegitimacy. So marriage is highly encouraged, and women with children are better supported and thus having more children is less of a burden. Which is the positive way of putting it. The negative way of looking at this is that women are stigmatized for any lifestyle which does not produce children. I think that this social structure has both good and bad qualities. The author of the article does not attempt to make any moral judgement on patriarchy as a system, although he points out that it does not have to be oppressive. Instead, his premise is not moral but statistical: non-patriarchal societies tend to be overtaken by patriarchal ones, simply because over several generations, non-patriarchal societies simply cannot keep up population-wise. Mixed societies, such as the US, tend to become more patriarchal over time, as the less patriarchal elements are eventually outnumbered. In the US, where the patriarchal elements are Christian conservatives, this won't destroy American society, despite the paranoid fears of "theocracy" professed by many liberals. In Europe, where the patriarchal elements are increasingly radical Muslims, there's a much greater risk that European society a hundred years from now will bear little resemblence to its current state.