Breaking the Spell: Religion as a Natural Phenomenon

Jared Diamond’s Guns, Germs, and Steel (1997) is an eye-opening exploration of very specific effects of geography and biology on the early development of agriculture in different parts of the world at different times. When the first agriculturalists domesticated animals, they naturally began living in close proximity to them, and this enhanced the likelihood of species-jumping by the animals’ parasites. The most serious infectious diseases known to humanity, such as smallpox and influenza, all derive from domesticated animals, and our farming ancestors lived through a horrific pruning in which untold millions succumbed to early versions of these diseases, leaving only those fortunate enough to have some natural immunity to reproduce. Many generations of this evolutionary bottleneck guaranteed that their later descendants would be relatively immune to, or have a high tolerance for, the descendants of those virulent strains of parasite. When these grand-offspring, living mainly in Europe, developed the technology to cross the oceans, they brought their germs with them, and it was the germs, more than the guns and steel, that wiped out large fractions of the indigenous populations they encountered. The role of agriculture in spawning infectious diseases, and the relative immunity to them that had evolved among the peoples who had lived through the ravages of the early days of agriculture, can be studied with some precision now that we can extrapolate backward from the genomes of existing species of plants, animals, and germs. Accidents of geography gave European nations a head start that goes a long way to explain why they were the colonizers rather than the colonized in later centuries.

Diamond’s Pulitzer Prize–winning book is deservedly well known, but not alone. There is a new generation of interdisciplinary researchers working to put together the biology with the evidence gleaned by centuries of work by historians, anthropologists, and archeologists. Pascal Boyer and Scott Atran are anthropologists who have done extensive fieldwork in Africa and Asia but who are also trained in evolutionary theory and cognitive psychology. Their recent books, Religion Explained: The Evolutionary Origins of Religious Thought (Boyer, 2001) and In Gods We Trust

(Atran, 2002), develop largely harmonious accounts of the major steps into the swamp that they and others have been taking. Then there is David Sloan Wilson, an evolutionary biologist who has been devoting himself in recent years to analyses that systematically exploit the Human Relations Area File, a database of all the world’s cultures compiled by anthropologists. His recent book Darwin’s Cathedral:

Evolution, Religion, and the Nature of Society (2002) makes the best case to date for the hypothesis that religion is a social phenomenon designed (by evolution) to improve cooperation within (not among

!) human groups. According to Wilson, religion emerged by a process of group selection, a controversial wrinkle in evolutionary theory that is dismissed by many evolutionary theorists as at best a marginal process whose conditions for success are unlikely to arise and persist for long. There are deep reasons to be skeptical about group selection, especially in our species, and precisely because Wilson’s thesis—religion as a cooperation-enhancer—is deeply attractive to many people, we need to brace ourselves to avoid wishful thinking. It is quite generally agreed among his critics that he has not (yet ) succeeded in making the case for his radical thesis of group selection, but even a roundly refuted scientific theory can make a major contribution to the steady accumulation of scientific understanding if the evidence marshaled for and against it has been scrupulously gathered. (For more on this point, see appendix B.) Here I will introduce the main points of agreement, as well as acknowledging the continuing points of contention, packing off most of the controversial details into the endnotes and appendixes, where those with a taste for them can (begin to) pursue their own deeper consideration of them.