トーマス・ジェファーソンの人生中心主義的思想

In Atlas Shrugged, Dr. Robert Stadler finds it "outrageous" that a genius such as John Galt would have "performed a major revolution in the science of energy, just as a means to an end." "Why," Stadler demands, "did he want to waste his mind on practical appliances?" Dagny Taggart answers: "Perhaps because he liked living on earth."

That reply summarizes the attitude of the American Enlightenment, most especially the attitude of the man whose birthday we celebrate on April 13: Thomas Jefferson.

Jefferson is best known as the leading "classical liberal" in American history. As the author of the Declaration of Independence, he outlined the political principles that launched the new nation. As the framer of the Virginia Statute for Religious Liberty, he spearheaded early efforts to separate church and state. As president of the United States, he fostered the fledgling country's continental expansion, setting the stage for America to become a global power.

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Jefferson was America's first life-centered philosopher.

But Jefferson was much more than a philosopher and statesman of freedom. His omnivorous appetite for the facts of nature (including human nature) is reflected in his only book, Notes on the State of Virginia , which contains exhaustive observations on every aspect of his state's natural and social environment: its flora, fauna, populations, mountains, rivers, geology, manufactures, and laws.

Even as president, Jefferson conducted botanical expeditions on which "he would climb rocks, or wade through swamps to obtain any plant he discovered or desired and seldom returned from these excursions without a variety of specimens." In his Washington residence "we see him not only with his beloved flowers, plants, books, and pet mocking-bird, but also with carpenter's tools, garden implements, maps, globes, charts, a drafting board, and scientific instruments" (I. Bernard Cohen, Science and the Founding Fathers , New York: Norton, 1995, p. 64). The East Room was cluttered with a huge fossil collection, while on the lawn frolicked young grizzly bears brought back by Lewis and Clark.

But this is not to say Thomas Jefferson was a scientific dilettante or dabbler. Far from it. After all, Jefferson is surely the only president who read Newton's Principia in Latin and could correct the leading astronomer of his day on its interpretation. But Jefferson liked to live on earth, and whenever he writes of his scientific activities, one is struck by the predominantly practical rather than contemplative cast of his mind.

Thus, what one sees at Jefferson's Monticello estate is a powerful mind bent to practical difficulties. An indefatigable gadgeteer, Jefferson filled Monticello—which he himself designed—with mechanical innovations: a complex clock in the front hallway, dumbwaiters, a revolving bookstand, a portable writing table, an invention to duplicate letters as he wrote, even a special ventilation and cooling system. The surrounding grounds serve as an elegant showcase for his interests in botany and scientific agriculture.

This very Jeffersonian attitude—that knowledge should enhance human life—was more broadly an Enlightenment attitude. Thus, in the year of Jefferson's birth, Benjamin Franklin established a "philosophical" organization with a strikingly life-centered agenda: to conduct "all philosophical Experiments that let Light into the Nature of Things, tend to increase the Power of Man over Matter, and multiply the Conveniences or Pleasures of Life." In 1769, this scientific organization became the American Philosophical Society.

From Jefferson, the society received designs for new inventions, observations on establishing weights and measures, and correspondence on everything from meteorology to fossils. He was perfectly at home discussing the heavens or mechanics with David Rittenhouse, an ingenious inventor and America's foremost astronomer; medicine and anatomy with the peerless Dr. Benjamin Rush; flora and fauna with Benjamin Smith Barton, the nation's leading botanist and anthropologist; or chemistry, physics, and electricity with the renowned Joseph Priestley.

Jefferson came to be held in such esteem by these eminent scientists that he was elected the society's president in 1796, a post they then refused to let him quit for nearly two decades. Historian Daniel J. Boorstin writes that this "was simple recognition of his leadership in American intellectual life" ( The Lost World of Thomas Jefferson , Chicago: University of Chicago Press, 1948, p. 23).

Why did this generalist command the enduring respect of specialists? Why, as Boorstin puts it, was Thomas Jefferson "the human magnet who drew them together and gave order and meaning to their discrete investigations" (p. 23)? Because Jefferson "possessed a mind more catholic than theirs and better able to see nature as a whole. Being a statesman, he persistently demanded the human implications of their science" (p. 23).

It is precisely because of his concern with the "human implications" of intellectual pursuits that Thomas Jefferson became the leader of the American Enlightenment. In countless arenas—scientific, cultural, and political—he focused the thinking of the nation's best and brightest toward the task of advancing not pure reason, but human life as an end in itself.

So, on his birthday this month, let us remember him not just as a Founding Father, architect, inventor, or scientist. Thomas Jefferson was all that, and something more. He was America's first life-centered philosopher.

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