Karl Popper, the eminent philosopher of science, wrote, "It is imperative that we give up the idea of ultimate sources of knowledge, and admit that all knowledge is human; that it is mixed with our errors, our prejudices, our dreams, and our hopes; that all we can do is to grope for truth even though it is beyond our reach."
Four centuries after Galileo, the world is still beset by those who claim access to an ultimate source of knowledge -- divine revelation through holy books or prophets. If there is a fundamental way to divide people in the world today it is into gnostics and agnostics, those who Know and those who grope. The former are still in the overwhelming majority, while the latter have meanwhile patiently created the scientific and technological infrastructure of modernity.
It was my pleasure once to visit Thomas Jefferson's home at Monticello. Everywhere one saw books, inventions and the other paraphernalia of a curious mind. Jefferson was an architect, horticulturist, paleontologist, archeologist, author and musician. Among his correspondents and friends were such scientists of the time as Joseph Priestly, Georges Louis Leclerc de Buffon, Edward Jenner, and, well, almost anyone else you'd care to name. He understood well the connection between science and democracy, as articulated by Jacob Bronowski: "The society of scientists must be a democracy. It can keep alive and grow only by a constant tension between dissent and respect, between independence from the views of others and tolerance for them."
With others of like mind, Jefferson laid the foundations of a new political paradigm, one not beholden to ultimate sources of knowledge or the "divine rights" of kings. It was a noble experiment, by and large successful, one that must be continuously defended against those who Know. As I toured the beautiful precincts of Monticello, it was clear I was in the company of a groper, a man by no means perfect, who knew that the perfection of truth was a noble human enterprise, not to be completed in his lifetime, if ever.