Enlightenment Thinkers

The Enlightenment was a broadly based intellectual movement across many countries that had an enormous impact. Enlightenment thinkers offered new ideas and perspectives on the sciences, philosophy, and politics. What we most often remember this movement for today is the contribution it made to our ideas of democratic government and the revolutions it inspired, such as U.S. Independence and the French Revolution. Learn about the broad trends and main ideas of the most famous Enlightenment thinkers here.

Enlightenment Thinkers – Definition

To devise a sound Enlightenment thinkers' definition, let's first consider the definition of the Enlightenment. Enlightenment thinker Immanuel Kant defined Enlightenment as the "human being's emergence from his self-incurred immaturity."¹

Kant suggests that being Enlightened meant learning to reason and then daring to use your full potential to think, learn, and understand the world around you. The origins of the Enlightenment grew out of the Scientific Revolution. With the triumphant explanation of much of the natural phenomena in the world through science, reason, observation, and experimentation, some Enlightenment thinkers now sought to explain human behavior, society, and institutions scientifically.

Therefore, we arrived at a definition of Enlightenment: an intellectual movement from approximately the 1680s to 1820s that emphasized reason as primary knowledge to explain human behavior and the world. So, the most suitable Enlightenment thinkers' definition is the group of intellectuals who used reason to guide their philosophy. For politics, this meant critiquing existing institutions and proposing alternatives.

Enlightenment Thinkers – Timeline

As noted above, the Enlightenment is usually considered to run from approximately the 1680s to the 1820s. See some of the critical events and fundamental works by Enlightenment thinkers on the timeline below:

Fig. 1 - Enlightenment Thinkers Timeline. Made by the Author Adam McConnaughhay, StudySmarter Originals.

Most Famous Enlightenment Thinkers

The list below includes some of the most famous Enlightenment thinkers. See a summary of some of the Enlightenment thinkers' ideas below or click the links to see more detailed explanations of their lives and ideas.

• Thomas Hobbes
• René Descartes
• John Locke
• Denis Diderot
• Voltaire
• Jean-Jacques Rousseau
• Montesquieu
• Immanuel Kant
• Adam Smith
• David Hume
• G.W.F. Hegel
• Jeremy Bentham
• Mary Wollstonecraft
• Francois Quesnay

This list is far from exclusive, and there were many more philosophers, writers, scientists, and poets that could be considered necessary Enlightenment thinkers. Still, these are often considered some of the most famous Enlightenment thinkers and certainly the most influential!

Fig. 2 - Portrait of John Locke

Enlightenment Thinkers' Ideas

The most famous Enlightenment thinkers proposed many influential ideas. They contributed many ideas to philosophy, behavioral sciences, and natural sciences.

However, for our purposes of studying history, it's best to focus on their political ideas that helped shape events in their day and continue to be influential today. Enlightenment thinkers proposed several noteworthy political concepts.

Enlightenment Thinkers on Government

Debating the Social Contract: Hobbes, Locke, and Rousseau

One of the most influential ideas of the Enlightenment thinkers on government was the idea of the social contract. This came to define the relationship between government and its citizens, defining the duties for each.

Rousseau, therefore, proposed a new social contract based on his idea of the general will where the good of the collective guided government rather than the good of the individual or specific social classes.

All three of these ideas are influential.

• Hobbes's idea that we must give up our freedom and let government enforce order lends itself to government agents such as police ensuring our safety.
• Meanwhile, Locke's idea that government should primarily protect the rights of individuals and when they don't it should be replaced is also generally accepted.
• Rousseau was somewhat ambiguous on how government should be structured, but the idea that it generally should reflect the will of the people as a collective and not serve to the benefit of one class over another is also important to our ideas of democracy.

Fig 2 - Title page of Rosseau's Social Contract.

Montesquieu and the Separation of Powers

Montesquieu is one of the most influential Enlightenment thinkers on government. He argued for the separation of powers, where government authority was vested in three equally powerful branches, each with checks and balances on the other to prevent abuses. This idea has been implemented in most western democracies today.

Enlightenment Thinkers on Religious Toleration and Freedom of Expression

Most Enlightenment thinkers on government also expressed strong ideas of religious toleration and freedom of expression. In this regard are Locke, Rousseau, and the French philosopher Voltaire, who was highly critical of established institutions like the Church and what he considered a tyrannical monarchy in his native France.

Enlightenment Thinkers on Slavery and Women

One of the most significant critiques of the Enlightenment relates to the seemingly hypocritical views of Enlightenment thinkers on slavery and women.

Enlightenment Thinkers on Slavery

While many of the most important Enlightenment thinkers on government called for liberty, they were often silent at best and at times contradictory on their views of slavery.

In the Thirteen British Colonies of North America that became the United States, some Enlightenment thinkers, such as U.S. Declaration of Independence author Thomas Jefferson, were themselves enslavers even while they called for liberty. German Enlightenment thinker Immanuel Kant expressed views of a racial hierarchy where Blacks and indigenous peoples were lesser than whites.

However, other Enlightenment thinkers, such as Rousseau and Benjamin Franklin, were publicly hostile to slavery and condemned it, even if they were not as outspoken on it as they were on other issues. The French Revolution, largely inspired by the Enlightenment, led to the abolition of slavery and the ideas of its Declaration of the Rights of Man helped spark the Haitian Revolution even if the reactionary regime of Napoleon temporarily reinstated it.

Another more positive view of the Enlightenment thinkers on slavery is that the ideals they espoused helped lead, at least in part, to the Abolitionist movement. Ultimately, the hypocrisy of calls for liberty, equality among citizens, and free speech proved to be incompatible with slavery, and as the ideas of the Enlightenment became more widespread and influential, they would come to be powerful weapons against the institution of slavery.

Fig 3 - Mary Wollstonecraft

Women

Another important critique of the Enlightenment thinkers was their exclusionary view towards women. Many of the most famous Enlightenment thinkers held opinions that were consistent with the traditional gender roles of women.

However, the Enlightenment salons and coffee houses where ideas were discussed often became new forums where women could participate and share their ideas. Some became outspoken critics. For example, the Olympe de Gouges wrote a direct response to the Declaration of the Rights of Man with her Declaration of the Rights of Woman. Mary Wollstonecraft's A Vindication of the Rights of Woman advocated for equality for women and more educational opportunities.

These critiques and the newfound space for women to participate eventually led to more equality and representation. Similar to the issue of slavery, the Enlightenment thinkers may not have always fully lived up to their ideals at the time, but those ideals were eventually influential in bringing about positive change.