Darwin's Cathedral: Evolution, Religion and the Nature of Society [Paperback]

David Sloane Wilson first acknowledges that traits which promote us to sacrifice ourselves "for the good of the group" are unlikely to spread in a population. He find great value in fields like evolutionary psychology for finding innate human psychological traits that promote individual reproduction and survival. However, he also takes a thought provoking look at important transitions in evolutionary history and finds that under certain special conditions, individuals become united and begin to function in a very real sense as a larger organism. Genes become united into chromosomes, cells become organisms, organisms become hives.

None of this is new so far of course. What is unique is the claim that some of these transitions cannot be explained without having some form of competition between groups whose traits are widely divergent. The basic problem is that behavior that allows one group to fare better than another must also allow the individuals to survive and reproduce within their own group. So self-sacrificing behavior that makes a group of berzerkers unbeatable in battle against other groups has a hard time taking root _within_ the group of berzerkers unless it also serves them there. Wilson claims that the bias against seeing selection occurrring at multiple levels, especially by the way genetic fitness calculations are averaged, prevents most biologists from seeing "group selection" when it does occur. He then proposes that the missing piece is human moral systems themselves, which provide mechanisms that lower the cost of behavior "for the group" in terms of individual fitness.

For example, social controls such as rewards and punishments are known to strongly foster cooperation even though cooperation is very fragile otherwise. We have tended to see this either in terms of individual self-determination or entirely in terms of social pressure. Wilson's view allows a middle ground, of innate traits which social controls can leverage powerfully to produce cooperation. Wilson's main point is that such traits probably require a multi-level selection theory to explain.

Wilson uses scholarly study of religion from a variety of fields to illustrate how human behavior shows evidence of forming groups as adaptive units in the evolutionary sense. This was an idea that was proposed by Darwin (thus "Darwin's Cathedral") and seen as fundamental by many social scientists, but was roundly rejected for the difficulties it brings into population models of evolution. In addition, the recent critiques often brought to bear on social science sometimes tend to see social science concepts such as those of Emile Durkheim as something needing to be slashed and burned rather than just seen in a new light. Wilson takes a new look at Durkheim's functionalist view of society and the various critiques of it, and finds plenty of archaic ideas, but also notes that the central theme of religion serving to unify human groups remains out of the ashes.

In Darwin's Cathedral, Wilson compares his view of religion as something that unifies human groups with the competing views of religion as a collection of arbitrary Gouldian "spandrels" or byproducts of evolution, the view that religion is a form of catchy imagination, and the Dawkinsian view that religious beliefs are mental parasites, and makes his case very well. He is very careful in his analysis and pulls from a wide range of scholarly material to make his case that, provided we are very careful about how we measure Darwinian fitness and very careful not to look for group selection where behavior can be explained otherwise, we can explain aspects of human behavior that simply can't be explained in terms of inclusive fitness for the genes of our relatives or even by playing games of reciprocal altruism.

Wilson makes many of the same points as Pascal Boyer does in "Religion Explained," but seems to tie things together more neatly with his theoretical framework. Since he is not limiting himself to psychological adaptations that solely promote individual survival and reproduction, Wilson has the added flexibility to pose adaptations for punishment and reward that serve social ends, which makes for much more elegant and powerful theory that explains a wider range of phenomena such as the tendency of human beings to see themselves readily as members of groups, their willingness to punish defectors, the the joy most of us get out of finding that we've helped someone else.

The only problem with this book is that Wilson takes on too much of a task here for one slim volume. The data on human religion is massive. I'm reminded of Frazer's classic "Golden Bough" and how virtually no one has ever actually read it all the way through in its single highly condensed volume, much less the dozen or so volumes he originally wrote. And yet he makes his point. Wilson also makes his point, and then draws from the massive data but seems to suffer in trying to navigate it all. He spends a lot of time looking at Calvinism from various angles for example. Everything he reviews seems to help him support his theory of religion as adaptive and unifying, but there is so much more to look at that in the end it feels oddly incomplete.

This is wonderful interdisciplinary theoretical work that deserves much more followup than a single person can possibly give it.

To Wilson's credit, he has written carefully about both scientific and religious issues, and readers with an interest in either field will find that he has covered both fairly. His coverage of the science involved begins with an interesting history of "the wrong turn" evolutionary theory took fifty years ago, when it deliberately ignored the influence of group selection. Especially if one accepts that there is for our species not only an inheritance of genes, but also an inheritance of culture, evolutionary influence by and upon religious groups, especially in light of the examples Wilson discusses, now seems obvious. For instance, evolution often studies population changes due to gains and losses from births, deaths, and in the case of religion, conversion and apostasy. The early Christian church is shown to have made gains compared to Judaism and Roman mythology because of its promotion of proselytization, fertility, a welfare state, and women's participation. There is a temple system in Bali dedicated to the water goddess essential for the prosperity of the rice crops; "those who do not follow her laws may not possess her rice terraces." The religious system encompasses eminently practical procedures for promoting fair water use and even for pest control. Religious morality is shown to build upon the principles of the famously successful computer strategy Tit-for-Tat. There is a significant problem, of course, in religions' dealing with other groups; it is not at all uncommon for a religion to teach that murdering those who believe in other religions is different from murdering those inside one's own religion. There is a degree of amorality shown in such competition, no different from the amorality that governs the strivings of ferns, sparrows, and lions.

Wilson's many examples are fascinating and easy to take, but _Darwin's Cathedral_ is not light reading; although Wilson wanted to write a book for readers of all backgrounds, he has not "'dumbed down' the material for a popular audience," and admits that there is serious intellectual work to be done in getting through these pages. There is valuable and clear writing here, however, and a new way of looking at religion which may become a standard in scientific evaluation.