World History Encyclopedia

Encyclopedie Frontispiece (by B.-L Provost/Charles-Nicolas Cochin II, Public Domain)

Encyclopedie Frontispiece

B.-L Provost/Charles-Nicolas Cochin II (Public Domain)

The Enlightenment (Age of Reason) was a revolution in thought in Europe and North America from the late 17th century to the late 18th century. The Enlightenment involved new approaches in philosophy, science, and politics. Above all, the human capacity for reason was championed as the tool by which our knowledge could be extended, individual liberty maintained, and happiness secured.

Origins of the Enlightenment

The Enlightenment is usually dated from the last quarter of the 17th century to the last quarter of the 18th century. During the Renaissance (1400-1600), when intellectuals and artists looked back to antiquity for inspiration, there arose the humanist movement, which stressed the promotion of civic virtue, that is, realising a person’s full potential both for their own good and for the good of the society in which they live. The ideas of the Enlightenment flourished from these roots and blossomed thanks to events like the Protestant Reformation (1517-1648), which diminished the traditional power of the Christian Church in everyday life. Most enlightened thinkers did not want to replace the Church, but they did want greater religious freedom and toleration.

The Enlightenment derives its name ‘light’ from the contrast to what was then seen as the ‘darkness’ of the Middle Ages. We now know that the medieval period was perhaps not quite as ‘dark’ as once thought, but the essential fact remains that religion, superstition, and deference to authority did permeate that period of human existence before philosophers began to challenge these concepts in the 17th century. It was no longer possible to simply accept received wisdom as truth just because it had been unchallenged for centuries.

Not for nothing were the enlightened philosophers also called ‘free-thinkers’.

In this new atmosphere of relative intellectual freedom, reason challenged accepted beliefs. Just like the practical experiments scientists were conducting in the Scientific Revolution to discover the laws of nature, so, too, philosophers were keen to apply reason to age-old problems of how we should live together in societies, how we can be virtuous, what is the best form of government, and what constitutes happiness. This was a battle of reason against emotion, superstition, and fear; its principal weapons were optimism for a better world and both the freedom and ability to question absolutely everything. Not for nothing were the new enlightened philosophers also called ‘free-thinkers’.

Pre-Enlightenment Thinkers

The Enlightenment was driven forward by philosophers, although given that many were also writers of non-philosophical works or even dabbled in politics, they might be better described today as intellectuals. These thinkers challenged accepted thought and, it is important to stress, each other, since there was never any consensus as to the answers to the questions everyone was trying to answer. What is sure is this process of examining and building knowledge was a long one, with different strands in different places. With hindsight, we can reconstruct the chain of ideas we collectively call the Enlightenment, but the participants at that time were aware that they were involved in a new movement of thought.

Leviathan Frontispiece

Leviathan Frontispiece

Abraham Bosse (Public Domain)

There is a group of thinkers who are often called ‘pre-Enlightenment’ philosophers since they established some of the key foundations upon which the Enlightenment was built. This group includes Francis Bacon (1561-1626), Thomas Hobbes (1588-1679), René Descartes (1596-1650), Baruch Spinoza (1632-1677), and John Locke (1632-1704).

Bacon stressed the need for a new combined method of empirical experimentation (i.e. observation and experience) and shared data collection so that humanity might finally discover all of nature’s secrets and improve itself. This approach was adopted by many enlightened philosophers. Bacon’s thoughts on the need to test our knowledge to see if it is actually true and his belief that we could build a better world if we all applied ourselves were also influential.

Hobbes, an English politician and thinker, proposed the idea of a state of nature, a brutish existence before we got together into societies. Hobbes believed that citizens must sacrifice some liberties in order to gain the security of society, and they do this when they form a social contract between themselves, that is, a collective promise to abide by certain rules of behaviour. He also believed, because of his pessimistic view of human nature, where people act entirely out of self-interest, that a very strong political authority was required, his Leviathan, named after the biblical monster. These ideas and Hobbes’ attempt to disentangle philosophy, morality, and politics from religion would all inspire Enlightenment thinkers, either in support or in providing alternative models.

Descartes, a French rationalist philosopher, proposed that all knowledge must be subjected to doubt because our senses are unreliable, we may be dreaming, or we may be living in a deception created by an evil demon. Descartes’ conclusion of applying doubt to everything is his founding principle of indubitable truth Cogito, ergo sum ("I think, therefore I am"). From Decartes’ ideas came Cartesianism and the position that the mind and body (or matter) are two distinct things but, in some way that thinkers had yet to determine, they interact with each other. While some critics point out that Descartes’ hunting down of doubts can lead to absurdities and total scepticism, his strategy has importance for the Enlightenment since it demonstrates the value of questioning everything and not taking at face value knowledge we have inherited from previous generations – knowledge that may, in fact, turn out to be not knowledge at all but only belief.

René Descartes

René Descartes

Dedden (Public Domain)

The Dutchman Spinoza attacked superstition and challenged the traditional role of God in human affairs, suggesting God does not interfere in our everyday lives. Combining rationalism and metaphysics, Spinoza was greatly interested in science and believed that by using our reason and studying nature we could come to better know ourselves and the divine. He also called for greater religious toleration.

The Englishman Locke proposed that there should be limits on state power in order to guarantee certain liberties, especially the right to hold property, which he considered a natural right (i.e. it is not given by a government or law code). Locke’s perfect state has a separation of powers, and the government can only operate if it has the consent of the people. Further, citizens can overthrow a government if it does not perform its role of protecting their rights. Locke believed humans can work together for a common good. He believed that individuals are more important than institutions like absolute monarchs and the Church. He believed that all citizens are equal and the state should educate its citizens to be reasoned and tolerant citizens. More than any other thinker, perhaps, Locke’s ideas not only inspired other thinkers but also influenced real-world affairs.

There were many other thinkers that influenced the Enlightenment, but space precludes discussion of them here; men like the German polymath Gottfried Wilhelm Leibniz (1646-1716), who believed that all knowledge was interconnected. In short, a whole body of international thinkers had already come up with the essential playing cards of the Enlightenment game before it had even started. Later philosophers now reshuffled these, selected some, and rejected others in their search for the winning hand of just how humans should live and knowledge be acquired.

10 Key Enlightenment Thinkers

Having set the foundation, then, a new wave of thinkers set about building a new edifice of Western knowledge. Disagreeing just as often they agreed with each other, all of the thinkers had the common objective of finding a better world to live in.

Newton's Copy of Principia

Newton’s Copy of Principia

Andrew Dunn (Public Domain)

One of the first texts of the Enlightenment proper was the 1687 Principia Mathematica by Isaac Newton (1642-1727). Newton’s book is in many ways a culmination of the Scientific Revolution, and it presents the view that the world around us can be understood, and the best tool for that purpose is science, in particular, mathematics. In his discovery of the force of gravity (and others besides), Newton showed that empiricism and deduction were the best methods to increase knowledge. Philosophers took this approach in their own work. Newton also showed that there was harmony and order in nature, which was something that philosophers sought to recreate in human society.

The French philosophe Montesquieu (1689-1757) was mostly concerned with avoiding authoritarian government. Going beyond Locke, he researched the history of politics – essentially founding political science – and famously articulated a separation of powers between the executive, legislative, and judiciary. He is another thinker who advocates the protection of individual liberty through laws, non-government interference, and toleration. To give an idea of the battle with the Establishment many enlightened thinkers had to face, Montesquieu’s book The Spirit of the Laws was put on the Catholic Church’s Index of Prohibited Books in 1751.

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The French author Voltaire (1694-1778) "more than any other represented the Enlightenment to his contemporaries" (Chisick, 430). Less an original philosopher and more a destroyer of the old attitudes, Voltaire was critical of the power of the Catholic Church, he called for more individual liberty and religious toleration, and championed our power of reason and innate capacity for moral behaviour. Voltaire also chastised philosophers for not coming up with practical solutions to society’s problems.

David Hume (1711-1776) was a Scottish philosopher, who presented a positive view of human nature – we all possess a capacity for sympathy and a natural moral sense – but a sceptical view of religion’s usefulness. Hume believed knowledge comes only from experience and observation but also acknowledged there are some things we can never know such as, why is there evil in the world? Hume expanded the notion of reason to include emotion.

Jean-Jacques Rousseau Portrait

Jean-Jacques Rousseau Portrait

Maurice Quentin de La Tour  (Public Domain)

The Swiss thinker Jean-Jacques Rousseau (1712-1778) contributed with his mixing of Hobbes and Locke in stating that humans in a state of nature are free, equal, and have two basic instincts: a sense of self-preservation and a pity for others. The people must gather in a community based on consent and with the ultimate objective of that society being the common good. For Rousseau, the general will is a compromise where individuals sacrifice complete liberty to achieve the next best option: a restriction on liberty in order to avoid a situation of no liberty at all. Whatever the general will turns out to be, that is the right one. Rousseau does recognise the need for a system of laws and strong government to guide the general will of the people when it might inadvertently err and to protect property, for him, an unfortunate creation of society. Rousseau was also concerned with ridding society of its obvious inequalities and injustices by having the state encourage its citizens through education to adopt a less self-interested approach to community life.

The thoughts of the Frenchman Denis Diderot (1713-1784) may be summarised as a humanistic belief in individual autonomy and the positive use of modern, non-religious, and, if possible, scientific arguments and methods to challenge age-old knowledge based on faith and superstition alone. Diderot was editor of the multivolume Encyclopedia, often described as the ‘Bible of the Enlightenment’ and summarised by N. Hampson as "an anthology of ‘enlightened’ opinions on politics, philosophy, and religion" (86). Diderot spent time advising both Catherine the Great (empress regent of Russia, 1762-1796) and Frederick the Great in Prussia (l. 1712-1786), examples of so-called ‘Enlightened despots’.

Adam Smith (1723-1790) was a Scottish philosopher and economist. He believed that economics is a science and follows certain laws, what he called the ‘Invisible Hand’. These laws, like any laws of nature, can be discovered through the use of reason. Smith called for free trade and limited interference in markets by governments, for which he is seen as the founder of liberal economics. A. Gottlieb describes Smith’s The Wealth of Nations as "the founding text of modern economics" (198).

The German philosopher Immanuel Kant (1724-1804) challenged the dominance of empiricism and rationalism in Enlightenment thought as he believed that some knowledge must be independent of sensation, examples given include our concepts of space and time. These things are a priori knowledge, things that we can think about without ever experiencing them directly. Consequently, Kant shifted the focus of philosophy to an examination of general concepts and categories. In ethics, Kant stated that moral worth comes from a person’s intentions and not from the results of their actions, which could be accidental. Good actions spring from following rules without exceptions like "never tell lies", what he called categorical imperatives. Kant also stressed the need for toleration, education, and cooperation between nations.

Immanuel Kant, c. 1790

Immanuel Kant, c. 1790

Unknown Artist (Public Domain)

Edmund Burke (1729-1797) stated that any nation and its institutions, including religious ones, were a product of a rich and long history, and so one particular generation should not simply cast away such time-tested guardians of our safety and liberty. Burke also thought that intuition and imagination were just as important tools as reason in understanding our world.

Thomas Paine (1737-1809), in his pamphlet Common Sense, famously called for the American colonies to rebel against British rule. Paine denounced slavery, was opposed to any form of privilege, believed all men are equal and should have the right to vote, and he called for a system of progressive taxation that could fund a fairer society.

Here we have considered only ten enlightened thinkers, but there were, of course, many more, but, unfortunately, space precludes their mention. The trend to apply enlightened thought to practical everyday problems was continued. Cesare Beccaria (1738-1794) called for prison reform and the end of excessive punishments for criminals. Mary Wollstonecraft (1759-1797) called for equal education opportunities for men and women and stressed the benefits to society of improving the situation of women. Jeremy Bentham (1748-1832) offered a way to measure the success of new laws with his utilitarianism and its "greatest happiness of the greatest number principle". Thinking about a better world had been the priority of the Enlightenment, but as the 18th century wore on, actually making one became the new priority.

A Great Mixing of Ideas

For ideas to spread and take root, there needed to be interaction between intellectuals, and this was achieved (beyond merely physically visiting each other) by several new means. The printing press allowed not only books to be distributed relatively cheaply but also treatises, pamphlets, and magazines. Never before had so much paper been passed across Europe. Ideas, and perhaps even more importantly, critical reaction to those ideas, and so the stimulus for yet more ideas, could be spread faster than ever before.

Salon of Madame Geoffrin

Salon of Madame Geoffrin

Anocet Lemonnier (Public Domain)

Another means for intellectuals to interact was the rise of academies and societies, where papers were published in in-house magazines, and meetings and debates were held. People also met in coffee houses to discuss new ideas. Yet another means of spreading ideas was the salon, particularly in Paris, although soon the idea caught on everywhere. These salons, so often managed by women, further aided the transmission of ideas not only between intellectuals but also different sections of society. For the first time, perhaps, philosophers, artists, politicians, and business people were able to meet together informally. Further, there was even some mixing of different levels of society in salons since the intellectuals and artistic creators could now meet aristocrats and those with great wealth, a meeting that often led to patronage, and so yet more ideas could be created.

The Impact of the Enlightenment

A key idea of enlightened thinkers was the belief that human existence could be improved through human endeavour. Developments in science and technology as well as progressive thinking in political philosophy meant that a better standard of living could be achieved for everyone. Reforms were championed that reduced society’s inequalities and diminished the impact of such negative but all-too-present phenomena as famine, disease, and poverty. Reformers called for real change in education so that more young people could attend school and become better citizens by developing their natural ability to reason. Just as individuals were to be left to pursue their own liberty and happiness in the new politics of liberalism, there developed the idea of laissez-faire economics, that is, minimising government interference to let the economy develop as the markets dictated it should. Modern liberal democracies then are based on the Enlightenment idea that some areas of life are no business of the state, a marked difference to societies of the Middle Ages.

To these general consequences of the Enlightenment, there can be added definite practical ones. As the Enlightenment specialist N. Hampson notes, the danger of studying the Enlightenment only in intellectual terms can lead to the conclusion that "the Enlightenment was everything in general and nothing in particular" (Cameron, 296). Some practical particulars include the end of the persecution of heretics, no more witches being burnt at the stake, serfdom coming to its final stage, and torture being removed from judicial processes. There were powerful movements to end slavery and the death penalty. The Church was formally separated from the state in some places, notably France. More universities and libraries were founded. Greater fairness was achieved in electoral systems.

The impact of the progress in science would be seen in the British Industrial Revolution (1760-1840) and its counterparts across the world. Many enlightened thinkers also foresaw the darker side of ‘progress’, such as an unrestrained individualism opposed to the common good and minority-controlled technological development that alienated large groups of people and destroyed the environment.

An Allegory of the Revolution

An Allegory of the Revolution

Nicolas Henri Jeaurat de Bertry (Public Domain)

It was not just the intellectuals who believed they could shape a better future. It took a long time for the high ideas of intellectuals to filter down to the lower classes, but descend they eventually did. Ordinary people of all classes now considered taking direct action to improve their lot in life and the political systems in which they lived. The two clearest examples of this action for a better world are the French Revolution and the American Revolutionary War. Revolutionaries in both events were inspired by and frequently quoted the works of enlightened philosophers; their revolutionary documents like the French Bill of Rights and the US Declaration of Independence were replete with the language these philosophers were using such as "inalienable rights" and "pursuit of happiness".

In some areas like the arts, there was a reaction to the Enlightenment and the new dominance of reason. This reaction was seen most clearly in the movement we call Romanticism (1775-1830), where, in literature and art, emphasis was given to new forms and modes of emotional and spontaneous expression.

Into the 21st century, the achievements of the Enlightenment, particularly liberty, freedom of thought, and toleration are still in existence in many places, but certainly not everywhere. As the historian H. Chisick points out these freedoms are not immune to ever-present threats like racism, political extremism, and religious fanaticism:

Apparently, the key values of the Enlightenment are not acquired once and for all. Rather, they must be appropriated by each generation and each culture in turn, or they will be submerged and lost. (160)

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Mark Cartwright

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