Jefferson’s Science and the Science of Temporizing

Jefferson ultimately found the Voltaire conjecture that mountains had once been under the seas unsatisfactory, for it appeared indemonstrable. He did not reject it any more than he rejected other unproven theories. Whether the deposit of shell fossils was the result of volcanic uplifts, or of ancient deluges, or of both was a matter that he could not resolve. He resorted to sarcasm cloaked in terms of theology. “How many millions of years it has cost Vulcan or Neptune to produce what the fiat of the Creator would effect by a single act of will, is too idle to be worth a single hour of any man’s life,” he wrote in the year of his demise. Was Jefferson in the end neither a Vulcanist nor a Neptunist, but a Creationist? Or was he simply demonstrating in his eighty-third year that he remained a temporizing ironist.

By temperament, he was far too inquisitive to consider any reasonable speculation a complete waste of time. By temperament he was also skeptical, and he possessed a continuing love of sarcasm until the final months of his life. But his skepticism and sarcasm masked his persistent theological creationism. For whether he invoked the Creator literally, or as a metaphor for Nature, he always relied on preconceptions about what constituted natural law. His position on the shell fossils is a good illustration of how Jefferson’s scientific mind functioned. Postponement of judgment in the absence of evidence was an idea that he understood. His position on the fossils allows us to witness his careful postponement of judgment for more than forty years—from the age of forty until three months before his death.

In the fifty years between 1786 and 1826 Jefferson’s theologically dependent scientific framework did not evolve. He wrote, to Charles Thompson. Paris, December 17, 1786, dismissing the brilliant and painstaking work of John Whitehurst, An Inquiry into the Original State and Formation of the Earth (1778). Whitehurst, a self educated man of humble origins, was a vastly superior scientist to Jefferson, both in terms of his methods and his technical accomplishments. Eventually elected to the Royal Society, he came from the artisan class that Jefferson despised, a mere maker of watches and compasses. But his competency in these realms was also superior to Jefferson’s. Whitehurst’s theory, which was based on scrupulous collection of data, far beyond Jefferson’s patience, was prophetic. His nascent thesis, that the Earth had undergone vast changes over the course of history, has stood the test of time. Jefferson’s response to Whitehurst was not to challenge his method or his evidence, but to engage in theological babble:

“I give one answer to all these theorists. That is as follows. They all suppose the earth a created existence. They must suppose a creator then; and that he possessed power and wisdom to a great degree. As he intended the earth for the habitation of animals and vegetables, is it reasonable to suppose, he made two jobs of his creation, that he first made a chaotic lump and set it into rotatory motion, and then waited the millions of ages necessary to form itself? That when it had done this, he stepped in a second time, to create the animals and plants which were to inhabit it? As the hand of a creator is to be called in, it may as well be called in at one stage of the process as another. We may as well suppose he created the earth at once, nearly in the state in which we see it, fit for the preservation of the beings he placed on it.”

The ideas Jefferson expressed to John P. Emmett, May 2, 1826 were similarly superstitious. Although by the 1780s, not only Whitehurst, but also James Hutton, were advancing theories of a changing geological universe. These were on the road to acceptance, with the rising influence of Charles Lyell, seven years after Jefferson’s death. But Jefferson rejected on theological grounds, both the emerging and ultimately dominant concepts of geological evolution and biological evolution. He died a few years too early either to accept or reject the contemporary theories that eventually stood the test of time. He discomfort with scientific speculation, revealed not only his theism, but a temperamental disposition that was not unknown in his politics — caution and temporizing. Elsewhere in the Notes he exercised this same prudence and on matters he considered momentarily unsolvable, he postponed judgment.

Jefferson’s notorious postponement of scientific judgment with respect to human equality occurs in every edition of the Notes. He could not prove it, but he argued systematically for the inequality of Sub-Saharan Africans with respect to the rest of the human race. He advanced it “as a suspicion only,” that black people of African origin “are inferior to the whites in the endowments of both body and mind.”