Bryan Caplan has initiated a series of posts where he will critique some aspects of Greg Clark’s book A Farewell to Alms. Caplan starts by disputing Clark’s implication that the Four Horsemen can increase per capita income simply by reducing population. I would say he makes some good points, but he does leave an opening:
…A plague might do the trick – it kills some outright, and weakens the rest. In the long-run, the survivors will have a higher material level of living. But this hardly makes the plague a “friend of mankind.” All it means is that after mass death, the frail, disfigured survivors will get to eat some extra calories beside the graves of their families. With friends like this, mankind doesn’t need enemies.
The after effects of disease vary quite a bit from pathogen to pathogen and person to person. Additionally, to some extent plague might be a partly exogenous variable, on occasion cutting through populations like a scythe for a few short years and then abating mysteriously for decades. I think this is why the conditions after the Black Death are a good case study which probably leans toward Clark’s contention. 25% of Europe’s population disappeared, but the survivors were not 25% less healthy or productive. In any case, add Econlog to your RSS to keep track of the debate.
Update: Arnold Kling is feeling Clark more than Caplan.