We di...

Henrich and Boyd (2002) were the first to propose a formal model of the role of attraction in cultural evolution. They came to the surprising conclusion that, when both attaction and selection are at work, final outcomes are determined by selection alone. This result is based on a determistic view of cultural attraction, different from the probabilistic view introduced in Sperber (1996). We defend this probabilistic view, show how to model it, and argue that, when both attraction and selection are at work, both affect final outcomes. Two naturalistic research programmes relevant to the explanation of cultural phenomena that started in the 70s — the evolutionary approach of Boyd and Richerson (1985, Richerson and Boyd 2005), and their collaborators, and the cognitive approach of Atran (1990, 2002), Boyer (1994, 2001), Hirschfeld (1996), Sperber (1996), and their collaborators — have to a certain extent converged over the years, the first, more evolutionary programme going into greater detail into the cognitive bases of cultural evolution, and the second, more cognitive programme paying an ever increasing attention to the evolution of mind and culture. Part of the reason why this relative convergence went almost unnoticed is the fact that these programmes were generally pursued in mutual ignorance with no discussion of the work in the other tradition, or, worse with misrepresentation, as when Sperber extended his criticisms addressed to Dawkins and memeticists to the work of Boyd and Richerson without attending to the relevant differences between these two approaches. In their article “On modeling cognition and culture,” Henrich and Boyd (2002) open a serious discussion of the cognitive approach. They overestimate, however, the points of divergence: we happen to agree with much of what they present as objections. Let us, to illustrate this point, add comment in square brackets and in italics to their concluding paragraph: The crux of Sperber, Atran and Boyer’s position is that the transmission of culture requires domain specific cognitive mechanisms [yes, with qualifications], and that therefore population dynamic models of culture 1 We thank Rob Boyd for veryuseful comments on an earlier version of this article. 2 We discuss the views of Boyd and Richerson in greater detail in Sperber and Claidière (in press).