The Enlightenment as Method: Rebirth, Science, Humanism, Reformation

On the long runway to take-off of the Enlightenment—and the modern world as we know it—were the intellectual movements of humanism, including the scientific revolution (late fourteenth and fifteenth centuries), the Renaissance (fourteenth to seventeenth centuries), and the Protestant Reformation (sixteenth and first half of the seventeenth centuries). Over roughly three centuries, human minds discovered experimental science and the lost Atlantis of classical culture and overturned the centuries-long monopoly of the Roman Catholic Church. 
The fuel of the scintillant historical sunrise of the Renaissance was the rediscovery of Greek and Roman thought, culture, and arts. This meant the rediscovery of man—the human being on earth as the natural, appropriate object of study and improvement, the first concern of thought. Man, not the divine, was the proper study of man. As the name suggests, humanism refocused thought on human matters. After centuries of utter preoccupation with the divine and supernatural, European thought returned to the primacy of human beings, their needs, and how reason might address human problems. 

Martin Luther
(1483–1546), German genius of the Protestant Reformation, sought truth not in the Catholic Church’s teachings but in “primary sources”—that is, the Bible. In a sense, both the Renaissance and Reformation sought truth in authority—the Renaissance in classical culture and the Reformation in the Bible. Both contributed to breaking up the monopoly of the Church of Rome. Luther, to say the very least, was no advocate of reason. Hatred for reason drips from his words. And the two most influential champions of reason in history?
“ ‘Aristotle is the godless bulwark of the papists. He is to theology what darkness is to light. His ethics is the worst enemy of grace.’ He is a ‘rank philosopher,’ an ‘urchin who must be put in the pig-sty or donkey’s stable,’ ‘a shameless slanderer, a comedian, the most artful corrupter of minds. If he had not lived in flesh and bones, I should not scruple to take him for a devil.’ As for St. Thomas, ‘he never understood a chapter of the Gospel or Aristotle. . . .  In short, it is impossible to reform the Church if Scholastic theology and philosophy are not torn out by the roots with Canon Law.’ ” 

The contribution of Luther to the Enlightenment, in a nutshell (no invidious pun intended), was to join in breaking the Church of Rome’s monopolistic authority in dictating “truth” on all matters. The alternative authority was one all Europeans knew: the Bible itself. The individual mind was empowered to seek its own truth in that “primary source.” One result was a proliferation of Protestant sects continuing to today. The “bottom line,” as accountants say, is that religion—not immediately, but in ensuing centuries—lost the power to command politics, law, education, science, social mores, publishing, theater, and much more.   

The Scientific Revolution

Humanism is identified with the experimental science of Francis Bacon (1561–1626), Nicolaus Copernicus (1473–1543), and Galileo Galilei (1564–1642) and the mathematical investigations of René Descartes (1596–1650), Gottfried Wilhelm Leibniz (1646–1716), and Isaac Newton (1642–1727). All except Newton are categorized as “precursors” of the Enlightenment because the achievements of natural science and mathematics earned for reason irresistible prestige across Europe (and later beyond). Sir Isaac Newton is viewed as the giant of the scientific revolution, with his seemingly “simple” mathematical laws to explain the movement of the earth and heavens; but he is deemed also a pillar of the Enlightenment. 

Empowering Reason with Methodology

The “agenda” of the Enlightenment became to identify how reason could be applied with the same success achieved by physics and mathematics to other fields, other questions. What method of reasoning carried with it built-in validity? Proof in science and mathematics depended upon logic—broadly, induction (observation and generalization) and deduction (deriving conclusions from accepted premises by syllogistic reasoning).

The early geniuses of the seventeenth century built on the work of Newton and a few philosophers to advance the idea of the world’s calculable regularity and prove that reasoning, which they sought to model on the ideal of mathematical reasoning, could enable men to achieve certainty about the world—certainty not requiring the guarantee of divine revelation.

Newton comments repeatedly on the proper application of reason as well as its conclusions: “As in Mathematicks, so in Natural Philosophy, the Investigation of difficult Things by the Method of Analysis, ought ever to precede the Method of Composition. This Analysis consists in making Experiments and Observations, and in drawing general Conclusions from them by Induction, and admitting of no Objections against the conclusions, but such as are taken from Experiments, or other certain Truths. For Hypotheses are not to be regarded in experimental Philosophy.” 

Enlightenment Ideas and Religion

Riding, above all, on the enormous reputation of Newton—and later of Thomas Hobbes (1588–1679), John Locke (1632–1704), Voltaire (1694–1778), Denis Diderot (1713–1784), and a few others—men in the seventeenth century and later in the eighteenth looked directly and with unconstrained minds at God, reason, nature, human thought, human societies and governments, and principles of production and trade—as well as at superstition, faith and dogma, the claims of all “authorities,” strictures of neoclassicism in the arts, what universities taught and with what justification, and the pretensions of “power.”

Nothing, in fact, was viewed by Enlightenment man as beyond questioning. But that unrestrained questioning brought down on them and their ideas laws, edicts, censorship, exclusion from “established” institutions, pillories, prisons, scaffolds, banishment and “transportation,” and social exclusion. 

In an age erected on religious faith and its establishments, the new methodology of reason inevitably sought justification of doctrines of faith in reason and nature. Its first product, initially in England and France, then America, was deism, not so much a movement or cult as a few fundamental convictions. One God, the architect and mechanic of the orderly and calculable world—not the personal God of Christianity—had created for mankind rewards and punishments and an obligation to practice piety and virtue. All men, the deists maintained, could perceive these truths and agree without divine revelation, holy books, or a church to mediate their relationship with God. In America, leaders of the Enlightenment, men like Ethan Allen (1738–1789), Thomas Jefferson (1743–1826), Benjamin Franklin (1706–1790), and Thomas Paine (1737–1809) were deists. So, too, were many later French revolutionaries; but by then, reason’s application to religion had yielded positions like skepticism, atheism, and materialism.

Industrial, Political, and Romantic Revolutions 

The Enlightenment produced intellectuals and new institutions in every field and in countries across Europe, then beyond. Broadly, in addition to creating modern philosophy, psychology, ethics, and natural and social sciences—to name but a few—the Enlightenment gave birth to the Industrial Revolution, political revolutions, and the Romantic revolution. In each, the methodology of reason dominated, setting standards of proof for truth, knowledge, and certainty.


Historians see the curtain on the Enlightenment in Europe as the French Revolution (1789–1799), which first thrilled men as the brilliant and infinitely promising triumph of Enlightenment theory and its application—and then, with the Terror and the Napoleonic Wars, shattered their confidence in reason, rational men, rational systems, humanism, and progress itself. 

Certainly, the spectacle of “Paris gone mad” (Edmund Burke), still under the banner of reason, ended the decades of unlimited confidence in reason and progress. The Enlightenment, of course, did not end; it lived on in the industrial, political, and Romantic movements; the momentum of the sciences; and the philosophy of the late Enlightenment in Germany, in particular.

In America, the nation born of the Enlightenment, its impact continued long into the nineteenth century. 

Modern or Postmodern?

The Enlightenment had changed the world with its tenets of reason, secularism (including separation of church and state), science, political freedom, economic liberalism (including free trade), and far more. They remain foundational ideas of modernity, although, for more than a century, they have come increasingly under attack by counter-Enlightenment philosophy (originating and maturing in Germany) and its latest manifestation, postmodernism.

Professor Stephen Hicks, author of the modern classic Explaining Postmodernism: Skepticism and Socialism from Rousseau to Foucault, summarizes postmodernism: “Postmodernism became the leading intellectual movement in the late twentieth century. It has replaced modernism, the philosophy of the Enlightenment. For modernism’s principles of objective reality, reason, and individualism, it has substituted its own precepts of relative feeling, social construction, and groupism. This substitution has now spread to major cultural institutions such as education, journalism, and the law, where it manifests itself as race and gender politics, advocacy journalism, political correctness, multiculturalism, and the rejection of science and technology.”

Do not count on the future to be “modern.”  That is an assumption easy to make because despite a century or more of anti-Enlightenment philosophy, and now postmodernism, the powerful methodology of reason that defined the Enlightenment—and won for us the modern world—has demonstrated its value almost beyond argument. But “argument”—reason, logic, evidence, and open debate—is not the method of postmodernism, which is the anti-Enlightenment.