An addendum to my comments on the posts on natalism. As I suggest below I think as a whole it is appropriate to model humans before 1800 as a conventional animal subject to Malthusian constraints. When a new crop (e.g., Champa rice, the potato) was introduced there would be a population increase, but that increase quickly reached a “natural” limit and growth would cease. On occasion disease (e.g., Black Death) or political disorder (e.g., the depopulation of Central Asia by the Mongol armies) would result in a population decrease. Interestingly, because of the Malthusian nature of the pre-modern world these societies in the wake of a population collapse would actually be more affluent per capita for several generations as the balance between labor and land would shift toward a surplus of the latter. It stands to reason then that I am highly skeptical of ideological pro or anti-natalist orientations within a culture. “Noble savage” populations regulated their population through birth spacing and infanticide not because they were ecologically conscious, but because their mode of production was such that the maximum number of humans supportable within their ecology was low. Large broods would be temporary as many children died of starvation.
On the other hand, I do suspect there may be elite driven cultural cycles which emerge from endogenous parameters within civilizations. I will here just refer you to Peter Turchin’s work. I do think usage of words like “vigor” may have some relevance to elite castes within pre-modern societies, though Turchin favors concepts which relate to social cohesion more precisely. But I doubt they are of particular relevance on a mass scale before the modern age. The average peasant was miserable, marginal and ignorant. The American farmer on the frontier was an exception, but that is because of the peculiar balance of the labor vs. land relationship in the New World until the “closing of the frontier.” By the time of American frontier had closed Western societies had to a great extent broken out of the Malthusian trap, so the history of the United States has never witnessed David Ricardo’s stationary state.