Diamond Closes the Loophole Boas Left Open

Boas, as Degler recounts, made a radical move for his era: observable differences between societies reflect "different histories, not different biological experiences." But notice what that argument leaves dangling. If histories explain the differences, what explains the different histories? An honest racist could concede Boas's whole point and simply push the biology back one step — sure, culture is proximate, but perhaps some peoples made more dynamic histories because of innate capacities. Boas's framework, on its own, doesn't foreclose that retreat.

Diamond's thesis is best read as the answer to precisely that follow-up question. Histories diverged "because of differences among peoples' environments" — the distribution of domesticable plants and animals, the orientation of continental axes, the accidents of geography. Diamond supplies the missing causal layer beneath Boas: not just culture, not biology, but geography, therefore culture. Together the two claims form a complete chain that leaves no gap where biological essentialism can re-enter.

But there's a cost worth naming. Boas's anti-racism came bundled with a deep contingency — cultures as particular, path-dependent, irreducible to any master variable. Diamond secures the anti-racist conclusion by installing a new determinism: geography as destiny. That's a real trade. The Boasian picture makes human societies free but leaves the door ajar for bad-faith biological explanations; the Diamond picture slams that door but risks making peoples mere expressions of their latitude and their local flora. One framework defeats racism with contingency, the other with a different necessity.

The deeper synthesis might be that both are doing the same rhetorical work at different scales: relocating the cause of human difference from inside people to outside them. Boas moves it from bodies to histories; Diamond moves it from histories to landscapes. Each step outward makes the explanation less flattering to winners and less damning to losers — which is perhaps why both arguments were experienced as morally radical, not just empirically novel.