تعادل شواهد و هنجارها در تکامل فرهنگی

Psychologists have long studied the ways in which individuals draw inferences from evidence in their environment, and the conditions under which individuals forgo or ignore those inferences and instead conform to the choices of their peers. Recently, anthropologists and biologists have given considerable attention to the ways in which these two processes intersect to jointly shape culture. In this paper I extend the BOP (“burden of (social) proof”; MacCoun, 2012) analysis of “strength in numbers” with a parallel account of “strength in arguments,” and examine ways the two processes might be linked. I compare these models to some leading accounts of individual learning and social transmission, suggesting opportunities for a closer integration of theory and research on cultural evolution across anthropology, biology, and psychology.

Cultures evolve through a balance of individual learning and social transmission (Boyd & Richerson, 1985). This is no less true in academic scholarship than in other cultural communities. Consider the cultural practice of null-hypothesis testing in social science. Most readers of this journal engage in this practice; we were taught the practice, given reasons for the practice, and completed problem sets that allowed us to explore the merits of the practice. But very few of us independently discovered the practice; we adopted it because the community had already adopted it, and we persist in the tradition even when editors try to nudge us into alternative practices (Fidler, Thomason, Cumming, Finch, & Leeman, 2004). And irrespective of one’s views of the evidence and logic behind null-hypothesis testing (see Cumming, 2014 for a recent overview), there is one feature we have adopted without any compelling mathematical or empirical reasons – the convention to set the critical rejection region at p = .05 (rather than, say, .02 or .20), as was proposed fairly arbitrarily by Fisher (1928, p. 45). Thus, null-hypothesis testing involves two issues: Where to place the threshold, and how strictly and uniformly to place the threshold. But at a meta-level, it illustrates the same issues with respect to two other thresholds – our epistemic and social thresholds for adopting that .05 threshold.