The Age of Enlightenment, sometimes called the Age of Reason, refers to the time of the guiding intellectual movement, called The Enlightenment. It covers about a century and a half in Europe, beginning with the publication of Francis Bacon’s Novum Organum (1620) and ending with Immanuel Kant’s Critique of Pure Reason (1781). From the perspective of socio-political phenomena, the period is considered to have begun with the close of the Thirty Years’ War (1648) and ended with the French Revolution (1789).
The intellectual leaders of the Enlightenment regarded themselves as a courageous elite who would lead the world into progress from a long period of doubtful tradition and ecclesiastical tyranny.
The Enlightenment was an intellectual movement, developed mainly in France, Britain and Germany, which advocated freedom, democracy and reason as the primary values of society. It started from the standpoint that men’s minds should be freed from ignorance, from superstition and from the arbitrary powers of the State, in order to allow mankind to achieve progress and perfection. The period was marked by a further decline in the influence of the church, governmental consolidation and greater rights for the common people. Politically, it was a time of revolutions and turmoil and of the overturning of established traditions.

THE EARLY ENLIGHTENMENT: 1685-1730
The Enlightenment’s important 17th-century precursors included the Englishmen Francis Bacon and Thomas Hobbes, the Frenchman Renee Descartes and the key natural philosophers of the Scientific Revolution, including Galileo, Kepler and Leibniz. Its roots are usually traced to 1680s England, where in the span of three years Isaac Newton published his “Principia Mathematica” (1686) and John Locke his “Essay Concerning Human Understanding” (1689)—two works that provided the scientific, mathematical and philosophical toolkit for the Enlightenment’s major advances.
Locke argued that human nature was mutable and that knowledge was gained through accumulated experience rather than by accessing some sort of outside truth. Newton’s calculus and optical theories provided the powerful Enlightenment metaphors for precisely measured change and illumination.
There was no single, unified Enlightenment. Instead, it is possible to speak of the French Enlightenment, the Scottish Enlightenment and the English, German, Swiss or American Enlightenment. Individual Enlightenment thinkers often had very different approaches. Locke differed from Hume, Rousseau from Voltaire, Thomas Jefferson from Frederick the Great. Their differences and disagreements, though, emerged out of the common Enlightenment themes of rational questioning and belief in progress through dialogue.
Although they saw the church – especially the Roman Catholic Church – as the principal force that had enslaved the human mind in the past, most Enlightenment thinkers did not renounce religion altogether. They opted rather for a form of Deism, accepting the existence of God and of a hereafter, but rejecting the intricacies of Christian theology. Human aspirations, they believed, should not be centered on the next life, but rather on the means of improving this life. Worldly happiness was placed before religious salvation. Nothing was attacked with more intensity and ferocity than the church, with all its wealth, political power, and suppression of the free exercise of reason.
THE HIGH ENLIGHTENMENT: 1730-1780
Centered on the dialogues and publications of the French “philosophes” (Voltaire, Rousseau, Montesquieu, Buffon and Diderot), the High Enlightenment might best be summed up by one historian’s summary of Voltaire’s “Philosophical Dictionary”: “a chaos of clear ideas.” Foremost among these was the notion that everything in the universe could be rationally demystified and cataloged. The signature publication of the period was Diderot’s “Encyclopédie” (1751-77), which brought together leading authors to produce an ambitious compilation of human knowledge.
It was an age of enlightened despots like Frederick the Great, who unified, rationalized and modernized Prussia in between brutal multi-year wars with Austria, and of enlightened would-be revolutionaries like Thomas Paine and Thomas Jefferson, whose “Declaration of Independence” (1776) framed the American Revolution in terms taken from of Locke’s essays.
In music, the sumptuous baroque music exemplified by the works of Johann Sebastian Bach and George Frideric Handel gave way to the clarity, structure and technical brilliance of composers such as Wolfgang Amadeus Mozart and Franz Joseph Haydn. In painting, artists expressed realism through allegory and social criticism. Works that exemplified this trend were the court portraits of the Spaniard Francisco Goya and the English painter William Hogarth’s street scenes of London. Gradually, the realism of the Enlightenment gave way to a period of romanticism in the arts.
THE LATE ENLIGHTENMENT AND BEYOND: 1780-1815
The French Revolution of 1789 was the culmination of the High Enlightenment vision of throwing out the old authorities to remake society along rational lines, but it devolved into bloody terror that showed the limits of its own ideas and led, a decade later, to the rise of Napoleon. Still, its goal of egalitarianism attracted the admiration of the early feminist Mary Wollstonecraft and inspired both the Haitian war of independence and the radical racial inclusivism of Paraguay’s first post-independence government.
~ Courtesy History.com
The heliocentric theory of Nicolaus Copernicus (1473-1543) started what historians call the “Scientific Revolution.”
Based on experimentation and reason, questioning previously held truths and searching for new answers, the scientific method transformed society by using science and reason rather than political or religious dogma to explain natural phenomena.
Galileo Galilei (1564-1642) made the first systematic studies of uniformly accelerated motion and improved astronomical observations, which helped to support Copernicanism. Edmond Halley (1656-1742) discovered the proper motion of stars and the periodicity of comets. Other significant scientific advances followed, including Isaac Newton’s (1643-1727) systematic application of algebra to geometry, which synthesized a workable calculus applicable to scientific problems.
The more notable figures in the Enlightenment were French thinkers known as philosophers:
- Voltaire, pen-name for François-Marie Arouet, the preeminent member of this group was a writer, historian, and poet. He emerged as the Enlightenment’s chief critic of contemporary culture and religion.
- Jean Jacques Rousseau, whose writings greatly influenced the political thinking of the time.
- Charles, Baron de Montesquieu challenged the idea of rule by a monarch and championed individual freedom.
- The philosopher Denis Diderot, in collaboration with Jean D’Alembert, founded the multivolume Encyclopédie designed to include all realms of knowledge. Many of the entries were written by other philosophes.
In German-speaking countries:
- Philosophers Gotthold Ephraim Lessing and Moses Mendelssohn championed the ideas of the Enlightenment.
- Immanuel Kant, Philosopher and physicist, wrote on ethics and morals and prescribed a politics of Enlightenment.
- Johann Gottfried von Herder, Theologian and Linguist, proposed that language determines thought.
In Britain included:
- Adam Smith, philosopher and economist
- David Hume, philosopher and historian
- Jeremy Bentham, philosopher
Enlightenment figures in North America included Thomas Jefferson, Benjamin Franklin, and Thomas Paine, all Deists.
Several monarchs during this period, including Frederick the Great of Prussia, Catherine the Great of Russia, and Joseph II of Austria,
were known as enlightened despots because they supported
many ideas of the Enlightenment.