Facts So Romantic

How Science Helped Write the Declaration of Independence

Benjamin Franklin kite key
Franklin Drawing Electricity from the Sky: Benjamin West

On July 4, 1776, representatives of thirteen colonies on the eastern shores of North America signed a Declaration of Independence from England. Winning independence was still a bloody war ahead, an unlikely outcome. Declaring independence was rashness, potentially carrying a death sentence for treason. Not, perhaps, what you would expect of well-educated men, many of them gentlemen steeped in the most sophisticated culture of their time. But steeped they were, and some of them really knew their philosophy and their science. The declaration they signed was no rough, back-woods piece of work.

The era was “The Enlightenment,” the “Age of Reason.” Science had become part of a cultured man’s way of thinking. Like their educated European contemporaries, signers of the Declaration, holding degrees from Harvard, Yale, Princeton, and William and Mary, regarded science as a wondrously valuable tool for acquiring knowledge, and viewed its achievements as the clearest manifestation of reason. Isaac Newton’s discoveries represented, for them, human intellect operating at its best.

Thomas Jefferson, only a few years out of university, was chosen by his more seasoned colleagues to draft the Declaration. They altered very little in his draft. During Jefferson’s seven years at William and Mary, beginning at age 16 in 1760, he had read law and also been mentored by a fine scientist, William Small. “It was my great fortune, and what probably fixed the destinies of my life that Dr. William Small of Scotland was then professor of mathematics, a man profound in most of the useful branches of science, with a happy talent of communication, correct and gentlemanly manners and an enlarged and liberal mind.” Jefferson had encountered Newton’s Principia and Opticks, and Newton’s calculus, in which he was to prove himself highly proficient. Jefferson played violin and cello and called music the “favorite passion of my soul,” but “the tranquil pursuits of science,” he wrote later, were his “supreme delight.” Public responsibilities left far too little time for them.

In the Declaration of Independence, Jefferson proclaimed, “We hold these truths to be self-evident….” In an earlier draft, he had written, “We hold these truths to be sacred and undeniable.” Whether it was Jefferson or Benjamin Franklin who introduced the change (scholars now favor Jefferson), “self-evident” sounds more blunt, more down-to-earth, as in, “It doesn’t take a rocket scientist to recognize that these things are true, King George.”

Pondering what “self-evident” meant to Jefferson, and why the words seemed appropriate to him, scholars have traditionally pointed to the influence of philosophers such as John Locke. The celebrated 20th-century science historian I. Bernard Cohen, in a book titled Science and the Founding Fathers, argued persuasively that we should look to science. In that context, “self-evident” suggests “axiom.” The encyclopedist John Harris (Jefferson had a copy of Harris’ encyclopedia in his personal library) spoke of science as founded on “self-evident principles.” Harris defined “axiom” as “such a common, plain, self-evident and received Notion, that it cannot be made more plain and evident by Demonstration.” Many of the educated founders (certainly Jefferson) studied Euclid, the ancient Greek known as the “father of geometry,” and encountered the words “self-evident” with regard to the “axioms” of geometry in the same textbook that Newton used. Locke himself wrote an essay on self-evident axioms in mathematics.

What did “self-evident” mean to Jefferson? Science historian I. Bernard Cohen argued persuasively that we should look to science.

However, since Euclid, the meaning of the word “axiom” had become less clear cut. By the time of Jefferson and his teacher William Small, people used “axiom” and “self-evident” in two senses, connoting either something like the “axioms” of geometry (unarguable Truth), or things that would be accepted as truth by people thinking in a new and corrected way. Thomas Aquinas in the 13th century had insisted that learned men can recognize some truths as self-evident that ignorant men cannot.

Nicolaus Copernicus, in the 16th century, promised his readers that if they would grant him “some postulates, which are called axioms” he could explain the apparent motions of the planets “with fewer and much simpler constructions than were formerly used.” Most scholars of Copernicus’ day regarded his “axioms”—such as, “all the spheres revolve about the sun as their mid-point, and therefore the sun is the center of the universe”—as anything but unarguable and self-evident. Johannes Kepler in the early 17th century used “axiom” for truths arrived at by experiment. One of Kepler’s axioms in his book Dioptrice was that “The refraction of crystal and of glass are very close to identical.” Unarguable, yes…but self-evident only to those who were aware of those experimental results. Isaac Newton, who studied these writings of Kepler, based his Opticks on eight “axioms” arrived at by experiment, not by basic, everyman observation. Thomas Jefferson surely had both meanings of the term “self-evident” in mind.

Most scholars of Copernicus’ day regarded his “axioms”—such as, “all the spheres revolve about the sun as their mid-point”—as anything but self-evident.

The Declaration does not say, “These truths are self-evident,” but, “We hold these truths to be self-evident.” King George certainly would have scoffed at the idea of Jefferson’s truths being self-evident! What do you and I make of the two meanings? Are equality and the rights to life, liberty, and the pursuit of happiness self-evident in the sense that they are unarguable by anyone’s standards? If not, then who or what are the corrected, enlightened beings—the we—who see them as such? It seems rather shockingly self-evident that neither Nature nor God (at least in this world) respects these ideals of equality and rights. People are not born physically or mentally equal. Their rights to pursue happiness are curtailed in ways that can’t be blamed on human activity alone.

The signers of the Declaration of Independence had high hopes that birthing their new nation could—like the leading-edge science of their age—represent human endeavor and reason operating at their best. That hope mirrored the optimism and newness of the age. The world is older now. Science and mathematics themselves have shown that “self-evident” truths of earlier science and mathematics are not Truth with a capital T. Euclid, so firmly established as bedrock, has yielded to non-Euclidean geometries. Different ancient religious traditions find that the received Truth of one does not agree with that of another. Post-modernism questions the possibility of objective truth.

We’ve left the world of “self-evident” and entered the world of “counter-intuitive.” Is anything self-evidently true…or good? Who will dare now shake a fist at rulers, nature, God, and ourselves, declaring, “We hold these truths to be counter-intuitive and not the way the world looks, but nevertheless true in some fundamental way, that all men and women are created equal, that they are endowed by their Creator with certain unalienable rights, that among these are life, liberty and the pursuit of happiness.” Do we believe that? If so, why do we so often leave this rhetoric hanging in the wind?

Kitty Ferguson is the author of eight books about astrophysics, the history of science, the lives of preeminent scientists, and the interface of science and religion. Her most recent book is Stephen Hawking: An Unfettered Mind/His Life and Work.

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