Cultural homogeneity is anti-Bayesian. According to the Gospel of Bayes, evidence can only be used to update pre-existing beliefs. If we consider any individua

Cultural homogeneity is anti-Bayesian. According to the Gospel of Bayes, evidence can only be used to update pre-existing beliefs. If we consider any individual issue, no matter what beliefs we start with, sufficient evidence will move all of us toward a similar endpoint. So for example as infants we likely start with some pretty weird hypothetical ideas, and by a roughly Bayesian process move toward common notions like object permanence. Since it is provable that Bayesian updating is the only way of knowing that is consistent, there is no magic short-cut to optimal answers, which means that a population with diverse starting points is in general going to have a few members that reach optimality fairly promptly while the rest of us are still flailing around. If we view cultures as systems for solving problems, this implies that cultural diversity will tend to get us to better solutions to those problems sooner than homogeneity. Nor will the same culture always be the fastest to currently optimal solution: the recent upsurge in interest in Buddhist psychology is an example of a culture that achieved a pretty good understanding of the mind quite a long time ago. By giving us a framework in which to understand the value of cultural diversity--including linguistic diversity--while at the same time placing the universality of Bayes' Rule at the centre of the knowing subject's experience, Bayesianism allows us to resolve the tension in Enlightenment humanism between a) valuing the unique and diverse forms of human expression, culture, language, etc and b) insisting there are universal principles that unite all humanity.