An Age of Enlightenment

1. If it is now asked, "Do we presently live in an
enlightened age?"
the answer is, "No, but we do live in
AN AGE OF ENLIGHTENMENT."
- “What is Enlightenment?”
Immanuel Kant, 1784

2. Late 1300s-1500s:
Renaissance and Reformation 
rediscovery of ancient learning and challenges to traditional thinking
+
Late 1400s-1600s:
Age of Exploration  discovery of new lands, people, flora, and fauna
=
Mid-1500s-1700s:
questioning authority + new explanations of nature 
Scientific Revolution
+
Late 1600s-Early 1800s:
laws of physical nature  laws of human nature?
Scientific Revolution  the Enlightenment

3. • Geocentric model: Ancient Greek philosopher Ptolemy put Earth at center of universe with
heavenly bodies in orbit around Earth.
• Heliocentric theory: Nicholas Copernicus, On the Revolution of Celestial Spheres (1543), put
Sun at center of universe with heavenly bodies including Earth in orbit around Sun.

4. Clockwork Universe
• Isaac Newton established laws of motion and universal gravitation.
• rational, predictable, mathematical Nature → clockwork mechanical universe; God = divine
watchmaker
• If reason explained Nature, Enlightenment philosophers believed it could also explain
human nature

5. Scientific Method
• Francis Bacon (New Atlantis, 1627) developed the
scientific method of experimentation and inductive
reasoning.
• René Descartes used deductive reasoning to prove
his existence. "I think, therefore I am"
(Meditations, 1641).
• Bacon’s inductive reasoning + Descartes’s
deductive reasoning = scientific method

6. Scientific Method
• Robert Boyle (Sceptical Chymist, 1661) founded
modern chemistry.

7. Renaissance-Era Medical Advances
• Andreas Vesalius conducted dissections to produce the well-illustrated anatomy book
On the Fabric of the Human Body (1543) and was court physician to Charles V.

8. Renaissance-Era Medical Advances
• William Harvey mapped the circulatory system was physician to English kings James I and
Charles I.

9. Renaissance-Era Medical Advances
• Anthony van Leeuwenhoek developed the microscope.

10. Later Medical Advances
• Edward Jenner
developed a smallpox
vaccine in 1796.

11. The Enlightenment
• Philosophical counterpart to the
Scientific Revolution
• Mid-1700s centered in France but
through Europe and to Americas
• Influenced the American Revolution
(1775-1783) which in turn influenced
the French Revolution (1789-1815),
Haitian Revolution (1791-1804), and
Latin American Revolutions (1808-
1833)

12. • Enlightenment  new political, religious, and economic theories
• Scientific principles were applied to resolving social problems and organizing
social institutions.
• Political theorists questioned the divine right of kings and challenged
political authorities with new theories based on the natural rights of man
and the right to rule coming from the consent of the governed.
• Theories of natural religion and religious toleration challenged religious
establishments (Catholic Church).
• Economists questioned state-controlled mercantilism and argued for free
market capitalism.

13. Enlightenment philosophers, called philosophes, believed humanity could be
changed for the better through never-ending progress guided by human reason.
Philosophes
• studied the social contract
• identified natural rights
• questioned social inequality
• espoused egalitarianism
• wanted reformed government
• desired legal equality and fair justice
• promoted science
• sought human progress through education
• encouraged religious tolerance

14. Enlightenment is man's emergence
from his self-imposed immaturity
[which is the] inability to use one's
understanding without guidance
from another.
- “What is Enlightenment?”
Immanuel Kant, 1784

15. Literate Public
• The Enlightenment was possible because of increased literacy.
• Printing  widely available texts on religion, history, science, and literature
• 1600s: Over 500,000 books published
• 1605: First newspaper published
• 1663: First literary periodical published
• 1700s: Nearly one million books published
• Political censorship was widespread, especially in France. Sweden (1766) and
Denmark-Norway (1770) were first to guarantee freedom of the press.

16. Literate Public
• Increased literacy  public opinion
• General public = educated elites
• The people = illiterate masses
Above:
High class aristocratic public
Left:
Low-class masses of people

18. The Social Contract - Thomas Hobbes
• Leviathan (1651): State of nature before formation of
human societies was "continual fear and violent death"
and "solitary, poor, nasty, brutish, and short.“
• The state receives absolute sovereignty from social
contract rather than God.
• Individuals surrender personal liberty to the state in
return for collective security.
• reflected the results of the English Civil War (1642-1651)
• King Charles I, defender of divine right, was defeated by
the republican Commonwealth which acted as a military
dictatorship under Lord Protector Oliver Cromwell.

19. The Social Contract - John Locke
• In An Essay Concerning Human
Understanding (1689) and Two Treatises of
Government (1689) argued humans are
born as tabula rasa (blank slate)
• Good or bad behavior mirrors how people
are treated; can improve through education
and environment.

20. The Social Contract - John Locke
• State sovereignty is received from the
consent of the governed.
• Individual rights are not surrendered in the
social contract.
• The role of the state is preservation of
natural rights to life, liberty, and estate
(private property).
• If the state fails, citizens are entitled to
revolt.
• Heavily influenced the American Declaration
of Independence.

21. The Social Contract - John Locke
• Reflects results of English Glorious Revolution (1688)
• Catholic King James II was overthrown at behest of
Protestant Parliamentary leaders. William III and
Mary II then signed the English Bill of Rights (1689)
• Created constitutional monarchy with limited royal
power and guaranteed individual rights

22. Baron de Montesquieu
• Spirit of the Laws (1748) called for
constitutional government
• Separation of executive, legislative, judicial
powers and due process of law including fair
trial, presumption of innocence; freedom of
thought, speech, and assembly; and an end to
slavery.
• Heavily influenced the U.S. Constitution.

23. The Social Contract - Jean-Jacques Rousseau
• The Social Contract (1762): Argues for small, direct
democracies in which state authority is derived from
popular sovereignty and reflects the general will of the
people.
• Rousseau advocated education to develop character and
moral virtue through use of reason

24. The Social Contract - Jean-Jacques Rousseau
• Rousseau heavily influenced Jacobin phase of French Revolution, and later, totalitarian
regimes that claimed to represent the general will, including the German Nazis and Soviet
Communists.

25. The Free Market
• Adam Smith’s Wealth of
Nations (1776) was anti-
mercantilism manifesto.
• Smith argued for laissez-
faire free market
capitalism guided by an
“invisible hand” and
value-added wealth
creation.