The dark side of the sighted watchmaker: How retrospective tinkering builds cultural traps.

Chater and Christiansen's social tinkering framework powerfully explains how directed, local innovations accumulate into complex cultural systems. However, the framework undertheorizes how the same cognitive and coordinative machinery systematically generates and entrenches maladaptive practices - magic, divination, taboo systems - that are socially coordinated and culturally cumulative yet instrumentally ineffective. I argue that retrospective causal reasoning under uncertainty, combined with the coordinative pressures central to social tinkering, predictably produces elaborate but materially costly cultural complexes.