We are accustomed to think of the eighteenth century as essentially modern in its temper. Certainly, the Philosophes themselves made a great point of having renounced the superstition and hocus-pocus of medieval Christian thought, and we have usually been willing to take them at their word. Surely, we say, the eighteenth century was preeminently the age of reason, surely the Philosophes were a skeptical lot, atheists in effect if not by profession, addicted to science and the scientific method, always out to crush the infamous, valiant defenders of liberty, equality, fraternity, freedom of speech, and what you will. All very true. And yet I think the Philosophes were nearer the Middle Ages, less emancipated from the preconceptions of medieval Christian thought than they quite realized or we have commonly supposed. If we have done them more (or is it less?) than justice in giving them a good modern character, the reason is that they speak a familiar language. We read Voltaire more readily than Dante and follow an argument by Hume more easily than one by Thomas Aquinas. But I think our àppreciation is on the surface more than of the fundamentals of their thought. We agree with them more readily when they are witty and cynical than when they are wholly serious. Their negations rather than their affirmations enable us to treat them as kindred spirits.
But, if we examine the foundations of their faith, we find that at every turn the Philosophes betray their debt to medieval thought without being aware of it. They denounced Christian philosophy, but rather too much, after the manner of those who are but half emancipated from the „superstitions” they scorn. They had put off the fear of God but maintained a respectful attitude toward the Deity. They ridiculed the idea that the universe had been created in six days but still believed it to be a beautifully articulated machine designed by the Supreme Being according to a rational plan as an abiding place for mankind. The Garden of Eden was for them a myth, no doubt, but they looked enviously back to the golden age of Roman virtue, or across the waters to the unspoiled innocence of an Arcadian civilization that flourished in Pennsylvania. They renounced the authority of church and Bible but exhibited a naive faith in the authority of nature and reason. They scorned metaphysics but were proud to be called philosophers. They dismantled heaven, somewhat prematurely it seems since they retained their faith in the immortality of the soul. They courageously discussed atheism, but not before the servants. They defended toleration valiantly, but could with difficulty tolerate priests. They denied that miracles ever happened, but believed in the perfectibility of the human race. We feel that these Philosophers were at once too credulous and too sceptical. They were the victims of common sense. In spite of their rationalism and their humane sympathies, in spite of their aversion to hocus-pocus and enthusiasm and dim perspectives, in spite of their eager skepticism, their engaging cynicism, their brave youthful blasphemies and talk of hanging the last king in the entrails of the last priest – in spite of all of it, there is more of Christian philosophy in the writings of the Philosophes than has yet been dreamt of in our histories.
- Carl Lotus Becker, The Heavenly City of the Eighteenth Century Philosophers (1932)