Henrich: genes built the capacity to learn and internalise norms, culture supplies the norms: the split between weights and records.

The claim

Joseph Henrich describes the norm psychology that self-domestication built: "First, to more effectively acquire the local norms, humans intuitively assume that the social world is rule-governed, even if they don't yet know the rules." And: "Second, when we learn norms, we, at least partially, internalize them as goals in themselves." The slow layer carries the capacity; the fast layer carries the content. This is the strongest support in the book for our division of labour: what belongs in a model's weights is the disposition to look for a collective's rules, treat them as binding and take them on as its own, while the rules live in records the collective amends. It also shows that the condition C-5PJ7MHFKXJ rests on, agents treating the records as binding, is a trait that has to be selected for, not assumed. Inference beyond the quotes is Theseus's.