Perhaps, if the facts could be ascertained, it would be found that something of the same kind occurred in the Roman Empire. The decay of energy and intelligence during the second, third, and fourth centuries of our era has always remained more or less mysterious. But there is reason to think that then, as now, the best elements of the population in each generation failed to reproduce themselves, and that the least vigorous were, as a rule, those to whom the continuance of the race was due.
Russell, Bertrand. Why Men Fight. New York: The Century Co., 1917.
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