Jeffersonian republicanism, it is well known, was an attempt to instantiate irenic, self-sufficient government of and by an enlightened, mostly agrarian populus. He thought at times that the American confederation of states would eventually spread out and occupy the entire North American continent—perhaps even the South American continent—and prove itself an emulable model of governing for bellicose nations of the world across the Atlantic Ocean to follow. In that regard, Jefferson aimed to export his republicanism.

One large problem Jefferson faced apropos of exporting his republicanism—and it was a problem of which Jefferson was fully aware—concerned the avowed climatic inferiority of the New World and its effects on America’s biota. It was generally conceded even by many who lived in the New World that its climate was inferior to that of Europe. Given climatic inferiority, it was not unreasonable to assume also that its biota, affected by climate, could not thrive. There was, after all, no animal in the Americas comparable to the Old World elephant, there was the uncivilized state of Native Americans, and there was the yellow-fever epidemic that struck Philadelphia in 1793 and decimated its population.

The world’s foremost naturalist George Louis Leclerc, better known as Comte de Buffon, had much to say about differences in the climates of the Old World and New World in his 36-volumes Natural History (1749–1800). In effect, Buffon argued for the defectiveness of America’s biota, due to the inferiority of its climate. Jefferson quotes Buffon on nature’s impotency in the Americas, “La nature vivante est beaucoup moins agissante, beaucoup moins forte” (Living nature is much less active, much less forceful [in America]).

All forms of life were smaller—animals being “four, six, eight, and ten times” so—and less robust in the New World than in the Old World. Where Buffon tread scientifically, others—e.g., Corneille de Pauw, Abbé Raynal, and William Robertson—followed. Raynal even claimed that people or animals transported to America would degenerate over time. These scientists were challenging Jefferson’s claim that America would ever be taken seriously as a model of government of and for the people for European nations eventually to follow.

The problem for Jefferson was essentially this. If the confederation of states should ever be taken seriously as a model of just republican governing, one would have to show at least that the Americas, compared to European nations, were not climatically deficient. The New World, he would have to show, was teeming with minerals, plants, and animals no less, or if not more, than the Old World.

That in gist is a large part of Query VI of Jefferson’s Notes on the State of Virginia. Having discussed the minerals and vegetables in Virginia and to a lesser extent in other lands nearby, Jefferson turns to a discussion of animals.

Jefferson, just prior to discussion of Buffon’s thesis, begins with a sockdolager, which is doubtless aimed at Buffon: the curious remains of an enormous animal, resembling in some respects an elephant and in other respects a hippopotamus, but much larger than both—“six times the cubic volume of the elephant” and “the largest of all terrestrial beings.” That in itself intimates that “both sides of the globe are “warmed by the same genial sun,” have soil of the same chemical composition, and have fruits and grains that yield the same “rich chyle.” If there are differences in species of animal in the two hemispheres, they are not due to climate, but due to their creator. “Every race of animals seems to have received from their Maker certain laws of extension at the time of their formation. … Below these limits they cannot fall, nor rise above them. What intermediate station they shall take may depend on soil, on climate, on food, on a careful choice of breeders. But all the manna in heaven would never raise the Mouse to the bulk of the Mammoth.”

Jefferson then turns directly to Buffon, who asserts that animals common to the Old and New Worlds are smaller in the latter; that animals endemic to the New World “are on a smaller scale”; that animals domesticated in both have degenerated in the New World; and that the New World has fewer species of animal. The explanation for Buffon is “that the heats of America are less, that more waters are spread over its surface by nature, and fewer of these are drained off by the hand of man.” In effect, Buffon argues that “heat is friendly, and moisture adverse to the production and development of large quadrupeds.” Thus, the superiority of the climate of the Old World is the result of its hotness and dryness.

On supposition of the truth of Buffon’s hypothesis—“we are not furnished with observations sufficient to decide the issue”—how is it, asks Jefferson, that vegetables thrive in hot and wet climates? And do not animals thrive where vegetables thrive? Moreover, if the New World is cold and wet, how is it that the skeletal remains of an animal of such bulk as the Mammoth is to be found there and not in the Old World?

Jefferson next turns to three tables, in which animals of the Old World are compared to those of the New World. Concerning the former, Jefferson uses animals dissected by Buffon and D’Aubenton, “and are of such subjects as came casually to their hands for dissection.” Concerning the latter, Jefferson is clear that his samples are often biased—viz., that he often chooses samples marked by an asterisk “deemed among the largest of their species” in order to challenge Buffon’s thesis. For instance, under “Aboriginals of Both,” the American bear is listed *410 pounds as compared to the European bear at 153.7 pounds, while under “Domesticated in Both,” the American cow is listed at *2500 pounds, while the European cow is 763 pounds. Jefferson’s reasoning is that even if Buffon’s sample is of an average bear or cow, or even of one slightly below average, one should not find instances of American bears or cows so much exceeding those of Europe, given the declared climatic inferiority of
America. That is why Jefferson concludes that the aim of his tables is “not to produce a conclusion in favour of the American species, but to justify a suspension of opinion until we are better informed, and a suspicion in the mean time that there is no uniform difference in favour of either.”

Yet Jefferson is not finished with the great European naturalist. So rash are Buffon’s conclusions concerning the inferiority of American animals that “it does not appear that Messrs. de Buffon and D’Aubenton have measured, weighed, or even seen those of America.” If their observations have come from “some travellers [sic],” he asks, were they natural historians, did they merely judge American animals by sight, and were they even acquainted with animals of their own country? “A true answer to these and other such questions would probably weaken their authority.” The rule of philosophy, Jefferson, following Newton, sums, is to ascribe “like effects to like causes,” and so any inferiority of size in one part of the globe or another is not to be ascribed to any “imbecility or want of uniformity in the operations of nature.”

Finally, Jefferson turns to Buffon’s trump card: Native Americans. Buffon, conceding that such savages are “about the same height as man in our world,” states that they are weak in body and mind, of small reproductive organs, glabrous, passionless when it comes to their women, driven only by the basest impulses, and fainéant, inter alia.

Jefferson—confining himself to the aboriginals of North America, as “of the Indian of South American I know nothing—then calls into question nearly everything Buffon has claimed apropos of Native Americans. They are, pace Buffon, affectionate with their children, capable of strong friendships, of keen sensitivity, vivacious, and intelligent, among other things. How is it that nature, for Buffon, seems to suspend its “operation as to the physical man of the new world,” and focus its activity on retarding his moral faculties? If we suspend judgment till more facts are gleaned and allow for their circumstances, says Jefferson, “we shall probably find that [Native Americans] are formed in mind as well as in body, on the same module with the ‘Homo sapiens Europaeus.’”

It is unsurprising that Jefferson would direct his attention at Buffon somewhere in Query VI, titled “Productions Mineral, Vegetable and Animal.” Fulfillment of his dream of an empire for liberty—whether continental, hemispheric, or global in scope—would require not merely some response to what was doubtless the received view—the American climate and, thus, biota, were deficient compared to those of Europe—but a vigorous, cogent response to it. Jefferson in Notes on the State of Virginia gave just that, and thereby removed a major scientific impediment to the view that the United States could be a model of Jeffersonian republicanism for the rest of the world to emulate.