[Earlier episode: Part 1]
The Old Testament was familiar with the likes of George Pine: long-lived, polygamous survivors of disaster who founded new societies in bounteous and conveniently depopulated landscapes. In the Isle of Pines, for his part, Neville described a second Eden, “always clothed in green, and full of pleasant fruits, and variety of birds; ever warm”, where nuts the size of apples hung from the trees, shellfish were in plenty, and a herd of quasi-goats (who kidded twins, twice a year) practically leapt onto the spit by themselves. The sheer idleness this plenty allowed, in fact, was what first bred in Pine “a desire for enjoying the women”. Looking upon the results, his grandson insisted to Van Sloetten that a little of “the culture that skillful people might bestow on it” might yet make the island “a paradise”. But in the beginning, when need – of food, land, clothing, or even shelter much beyond what the island naturally provided – was a thing unknown, it was a paradise already.
In Neville’s day, the best-known examples of rapid population growth were biblical. The descendants of Jacob (who lived to 147) had “multiplied exceedingly” in Egypt, from seventy to several hundred thousand, if not over a million, two centuries later. (Early modern calculations, and there were many, varied.) Little could be proven about Adam and Eve, but the Great Flood seemed to imply that a global population must have existed by Noah’s time – if only to justify the global extent of the punishment. Given orthodox estimates of biblical chronology, Neville’s contemporary Edward Stillingfleet explained, this meant that the whole Earth had been “fully peopled” in just over 1,600 years. And then there was Noah. Alone in the world but for his three sons and their wives after the Flood subsided, he had the massive job of filling three (or was it four?) continents with cities and even empires – hopefully in time for the disturbingly lengthy historical records of increasingly well-known civilizations (Egyptian, Assyrian, Chinese) to make sense.
When it came to rapid reproduction, early modern biblical chronologists were not short of ideas. The Jesuit Denis Pétau (1583-1652; Dionysius Petavius to his friends), Stillingfleet noted, “supposeth that the posterity of Noah might beget children at seventeen, and that each of Noah’s sons might have eight children in the eighth year after the flood, and that every one of these eight might beget eight more”, and so on, each generation surviving and reproducing for hundreds of years. The unbelievably named Jean du Temps (Johannes Temporarius; c.1500-1570) pressed still harder on postdiluvian loins; he suggested that Noah’s descendants, anticipating Pine’s goats, might have borne twins every year from age 20 – “on which supposition… he undertakes to make it appear, that in the 102[nd] year after the flood, there would be of males and Females 1,554,420”. Others went even further, giving Shem, Ham, and Japheth ten sons each, for example. Virtually the only limits to such blue-sky obstetrics were the chronologist’s imagination and the reader’s faith.
But not only were non-European sources raising tricky questions by Neville’s time; the Bible itself was also subject to novel skepticism. Here the standout entry in Neville’s era was Isaac La Peyrère’s Prae-Adamitae, appearing in English in 1656 as Men before Adam. Curious, well-travelled to the point of flightiness, and wishing only to convert the Jews and spur Christ’s return, La Peyrère poked a variety of holes in the usual reading of Genesis. Some reflected new discoveries (where did Americans come from?), others logical inconsistencies in scripture (whom did Cain marry?). The upshot was that Adam was not the father of humankind but only of the Jewish nation; the Pentateuch was a national, not a universal history; and God had created not one but two races, Jews and Gentiles, independently. The horrendous possibilities of a polygenist hypothesis would unfold slowly, flowering in the nineteenth-century notion of a multi-sided, existential war between biologically distinct, color-coded races. (This in turn bred fears about comparative population growth that are still with us, as debates about multiculturalism, bilingualism, and immigration reveal.) But as far as early multiplication went, La Peyrère’s eccentric exegesis offered a simple way out of a tight spot.
Few took it; even La Peyrère recanted, moved by his time in a Belgian prison. Yet the cracks in sacred history were too many to ignore. To fill them, a motley band of scriptural apologists – some of them remembered as founders of geology, others as cranks or not at all – turned to recent developments in science. The result was a second round of retrospective demographic fantasy, but with a difference. Earlier chronologists had based their calculations on the patriarchs’ longevity, polygamy, and tumescent joy in God’s goodwill; writing after Graunt, by contrast, theorists of the ancient Earth tethered their projections – much as Neville tied Pine’s – to the environment and human biology.
The work that set the tone, Thomas Burnet’s Sacred Theory of the Earth (printed in Latin in 1681; Englished in 1684), said little about multiplication. But it did argue that the Flood – caused by an implosion of the earth’s surface, releasing waters hidden underground – had transformed a once smooth landscape blessed by perpetual spring into a rugged, inhospitable, and wildly variable environment. Newton’s acolyte William Whiston blamed a comet for starting the flood, but agreed that both the “State of external nature” and the “State of mankind” had both changed radically. Whiston quoted Graunt and his fellow political arithmetician William Petty at length as guides to normal human increase in modern times; given that the antediluvians lived, Whiston estimated, forty times longer than the moderns, it stood to reason that they had forty times as many children, whose own reproductive lives overlapped with other generations’ for longer than in the present. The causes must lie, he thought, in “The much greater fertility of the Antediluvian Earth”, which supported more plants, animals and people “even on the same space of Ground” than the modern. Naturally as well as morally, the early Earth had been an Isle of Pines, sheer bounty breeding numbers and vice. Then the Flood changed everything.
At this point, several paths present themselves. One leads through a series of earnest, if inadvertently entertaining, attempts to defend scripture scientifically, by fleshing out a distinctive antediluvian biology. Did people who lived hundreds of years still go through puberty in their early teens, or closer to age 100? (And if the latter, why did Abraham and Sarah – still young things of 100 and 90, respectively – laugh when promised a child?) Did mothers nurse children for longer than in later ages? If so, would infant mortality have been lower, or pregnancies less frequent? A second road follows the development of “medical arithmetic”: the empirical study of populations’ physical and moral health in the present (though not without reference to God or biblical experience). But a third possibility takes us across the Atlantic and forward to 1760, to perhaps the last and most influential person to take Van Sloetten’s discovery literally: “gentle Puritan”, theologian, and amateur demographer Ezra Stiles.
Set sail for the third (and final) part of “Return to Penis Island”…
 Exodus 1:5-7.
 Edward Stillingfleet, Origines Sacrae (London, 1662), 539.
 Jed Z. Buchwald and Mordechai Feingold, Newton and the Origin of Civilization (Princeton University Press, 2013), survey this thoroughly.
 Stillingfleet, Origines, 556.
 Two good books on this are Colin Kidd, The Forging of Races (Cambridge University Press, 2006) and David N. Livingstone, Adam’s Ancestors (Johns Hopkins University Press, 2008).
 As the Trump 2016 campaign grinds on, further references seem unnecessary.
 William Whiston, The New Theory of the Earth (London, 1696), 100, 174-81, 282-300.
 Genesis 17:17, 18:10-12.
 Patrick Cockburn, An Enquiry into the Truth and Certainty of the Mosaic Deluge (London, 1750), ch.2, §3, “Of the time allotted to the nursing of Infants in the first Ages of the World”. I’ve written about this sort of thing here.
 The best book on this is Andrea Rusnock, Vital Accounts (Cambridge University Press, 2002).