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The leading theory in the social sciences is cultural determinism. Yet, it lacks plausibility as a scientific theory. It is often untestable. When tested, it frequently fails. Such failures are widely ignored because social scientists cannot conceive of a plausible alternative. Evolutionary social science1 may fit that bill.
Cultural determinism is based on cultural relativity—the notion that growing up in one society is so different from growing up in another that they cannot be properly compared. It is as though a resident of one country operates in a different reality from a resident of another because they speak a different language, believe a different religion, and so on. So societal differences are attributed to “cultural” differences. The problem with this “parallel universes” approach is that it flies in the face of scientific method and natural science (physics, chemistry, biology, etc.) that expects the same laws to hold good everywhere.
Up to now, evolutionary psychologists challenged cultural relativism by arguing that genetic influences cut across rearing environments—men being more physically violent in every society, for instance—but they had little to say about why societies are different, a sin of omission that surrendered much of the subject matter of the social sciences to cultural relativism. This is a pity because a natural-science approach to topics such as different forms of marriage (e.g., monogamy vs. polygamy) can be surprisingly successful whereas cultural determinism fails to explain the worldwide distribution of marriage forms.
Cultural determinism in a nutshell
Societal variation (or diversity) is the subject matter of cultural determinism. For sociologists and social psychologists, the key differences are attitudes to women and minorities, and class differences. Anthropologists focus on bodily decoration, marriage, sexuality, warfare, home construction, religion, language, subsistence economy, and so forth.
Such variation is commonly viewed by cultural determinists as ironclad evidence that societal differences are caused by “cultural” differences. A person imbibes the ideas of their society and goes on to behave much like everyone else there, whether they happen to live in a developed country or belong to an indigenous tribe.
In this vein, members of a society somehow come up with a set of rules about how to behave, rules that get passed on first by oral tradition, and subsequently by writing and electronic media in developed countries. Over time these rules change due to accumulated thoughts, such as religious traditions and bodies of law, as well as via random copying error, or drift, as illustrated by regional dialects of a language.
What is wrong with cultural determinism as science
Viewed as a scientific project, cultural determinism encounters several crippling problems. Its explanations are mostly circular. For instance, violent crime is attributed to a culture of violence. We never learn what causes some societies to be more violent in the first place. Instead, the outcome is used to explain itself—an exercise in circular reasoning that lacks scientific validity2.
The key explanatory constructs are generally moralistic (e.g., racism, sexism, lookism, imperialism). They take sides and prevent researchers from maintaining the sort of objectivity that is the key to good science.
Finally, cultural determinists assume that humans belong to a different scientific realm than all other evolved species on this planet. The upshot is that cultural determinism truly explains very little and the sciences that are infected by it make little or no progress.
Some of these problems may be illustrated by the issue of polygamous marriage that was the subject of a recent post. In accounting for the presence of polygamy in some societies, cultural determinists point to patriarchal attitudes, ignorance, and oppression of women. Yet, there is no evidence in favor of any of these moralistic explanations.
The evidence does, however, support exactly the same adaptive reasons for human polygamy as for polygynous mating systems of birds3. They are: a scarcity of males; the capacity of males to defend good territories (mirrored by wealth inequality); and the need of females to acquire disease-resistant genes for their offspring.
This is not to say that we can know everything we need to know about our own species by studying birds. What it is saying is that a cross-species comparative perspective can be enormously rewarding for understanding ourselves.
Judging from the empirical success of this evolutionary approach in explaining cross-societal differences in polygamy and the abysmal failure of cultural determinism, the future may belong to adaptationism. This is not the jaded concept of universals but an active scientific engagement with the great diversity of human societies.
1. Barber, N. (2008). The myth of culture: Why we need a genuine natural science of societies. Newcastle-upon-Tyne: Cambridge Scholars Press.
2. Barber, N. (2008) Evolutionary social science: A new approach to violent crime. Aggression and Violent Behavior, 13, 237-250.
3. Barber, N. (2008). Explaining cross-national differences in polygyny intensity: Resource-defense, sex ratio, and infectious diseases. Cross-Cultural Research, 42, 103-117.
