Predictive social science does not exist. Indeed, it seems to me that it cannot ever exist, since the behaviour to be predicted reacts to and is part… - William Hardy McNeill

Painting responded to the plague-darkened vision of the human condition provoked by repeated exposure to sudden, inexplicable death. Tuscan painters reacted against Giotto's serenity, preferring sterner, hieratic portrayals of religious scenes and figures. The "Dance of Death" became a common theme for art; and several other macabre motifs entered the European repertory.

Details of early domestications remain unclear. One must assume a process of mutual accommodation between humanity and various domesticable species. This involved rapid and sometimes far-reaching change in the biological character of domesticated plants and animals as a result of both accidental and deliberate selection for particular traits. Conversely, one can assume that a radical, if rarely deliberate, selection among human beings occurred as well. Individuals who refused to submit to laborious routines of farming, for instance, must often have failed to survive, and those who could not or would not save seed for next year's planting, and instead ate all they had, were quickly eliminated from communities that become dependent upon annual crops.

Birth control may in time catch up with death control. ...But for the present and the short-range future, it remains obvious that humanity is in course of one of the most massive and extraordinary ecological upheavals the planet has ever known. ...a sequence of sharp alterations and abrupt oscillations in existing balances between microparasitism and macroparasitism can therefore be expected in the near future as in the recent past.