Convergent Abstraction Hypothesis

Tl;dr Convergent abstraction hypothesis posits abstractions are often convergent in the sense of convergent evolution: different cognitive systems converge on the same abstraction, when facing similar selection pressures and learning in similar environments. It is a less ambitious alternative to 'natural abstractions hypotheses' and, in my view, likely to be true. Convergence may be real, useful, and empirically robust, while still being contingent and fragile under changes in architecture