This bone of contention is more interesting. Peterson claims that C-16 is based on the postmodern ‘Marxist’ idea that everything is socially constructed. Humans are born ‘blank slates’ which then accrue socially-fabricated identities. Peterson opposes this with a combination of Darwinian biologism (he’s fixated on evolved dominance hierarchies) and Jungian archetypes (which, following one of Jung’s tendencies, he roots in our deep socio-biological history).