{"id":9258,"date":"2019-01-09T15:25:39","date_gmt":"2019-01-09T14:25:39","guid":{"rendered":"http:\/\/cognitionandculture.local\/?p=9258"},"modified":"2023-07-24T15:05:00","modified_gmt":"2023-07-24T13:05:00","slug":"a-matter-of-taste","status":"publish","type":"post","link":"https:\/\/cognitionandculture.local\/blogs\/hugo-mercier\/a-matter-of-taste\/","title":{"rendered":"Blind imitation or a matter of taste?"},"content":{"rendered":"
For some varieties of cassava, complete detoxification is an effortful, complex, unintuitive process. Joe Henrich famously argued that the practice could only spread through blind, conformist imitation. But what if cassava just tastes better that way?<\/p>\n
***<\/p>\n[This post was co-written by Hugo Mercier and Olivier Morin]\n
In The Secret of our Success <\/em>(2015), Joe Henrich offers a grand tour of the best insights gene-culture coevolution theory has to offer. One of this theory’s longest-standing claims is that the collective ingenuity of cultural traditions often goes a long way further than individual creativity. Culture is good for our species. Another, much less intuitive claim, is that humans are predisposed to copy utterly opaque traditions blindly and uncritically. One of the most popular case studies supporting this view is certainly the processing of cassava, discussed in chapter 7\u2014On the origin of faith<\/em>\u2014of Henrich’s book.<\/p>\n Cassava (manioc) can be a great nutrient, \u201ctasty and filling,\u201d but some varieties contain a toxic amount of cyanide. If cassava is not properly processed, the cyanide creates immediate harm or, more insidiously, accumulates to generate long term damage, resulting in goiter or neurological problems. Fortunately, some South-American populations\u2014who first domesticated cassava\u2014have figured out a long and effortful process that makes cassava perfectly safe to eat.<\/p>\n Darna Dufour and her colleagues, on whose research Henrich relies here, have measured the cyanide content in cassava at its various stages of processing, and shown that it drops at each stage, until it reaches negligible quantities. Even though we now have a decent understanding of the underlying chemical reactions that allow this detoxification, the Tukanoans possess no such knowledge.<\/p>\n Why do they do it then? After all, this is a very effortful process: \u201cTukanoan women spend about a quarter of their day detoxifying manioc.\u201d<\/p>\n Regarding the first steps of the process\u2014up to and including boiling\u2014the answer is easy. As these steps remove the bulk of the cyanide, they have two obvious effects: they make the product less bitter, and they prevent cassava from causing immediate and violent sickness. Coming up with these techniques is nothing trivial, of course, and this makes the first point of gene-culture coevolution theory: culture is good for our species. It passes down intuitive, sensible, useful techniques that would be tricky for a single individual to invent.<\/p>\n But what about the second point? Is cultural transmission, in this instance, a matter of sheer faith? The last stages of cassava processing, in Henrich’s view, suggest as much. Once the cassava is boiled and its bitterness removed along with most of its toxicity, a tiny cyanide residual is left that may cause severe problems in the long run. Letting the manioc rest for a few days gets rid of this. How would Tukanoans know about this? As Henrich points out, they \u201cwould have rarely, if ever, seen anyone get cyanide poisoning, because the techniques work. And even if the processing was ineffective, such that cases of goiter (swollen necks) or neurological problems were common, it would still be hard to recognize the link between these chronic health issues and eating manioc.\u201d<\/p>\n Henrich\u2019s answer is that Tukanoans, like all humans, are endowed with a conformity bias, a tendency to follow what the majority of the people from their group does, even when that means engaging in apparently nonsensical, effortful behaviors. In his words, \u201csuch complex adaptations [as manioc processing] can emerge precisely because natural selection has favored individuals who often place their faith in cultural inheritance\u2014in the accumulated wisdom implicit in the practices and beliefs derived from their forebearers\u2014over their own intuitions and personal experiences.\u201d<\/p>\n This has convinced many readers. Indeed, cassava processing is becoming the go-to example for the role of blind faith in cultural transmission\u2014and the unimportance of individual cognition:<\/p>\n