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European History Unit 4: Scientific, philosophical and political developments (c. 1648–1815)

The Scientific Revolution and Enlightenment applied reason and observation to nature and society.

Covers: The Scientific Revolution, the Enlightenment, enlightened absolutism, new ideas about society, the rise of global markets

Study guide

The Scientific Revolution replaced reliance on ancient authorities with observation and experiment. Copernicus proposed a heliocentric (sun-centered) universe; Kepler showed that planets move in elliptical orbits; Galileo used the telescope to support heliocentrism and was tried by the Church; and Isaac Newton's laws of motion and universal gravitation explained the universe as a machine governed by natural laws. Francis Bacon promoted empiricism and the inductive method, while René Descartes emphasized deduction and reason ('I think, therefore I am'). Together they shaped the scientific method.

The Enlightenment applied reason to government and society. Thomas Hobbes argued in Leviathan that people need a strong ruler to avoid a violent state of nature, while John Locke argued that government should protect natural rights and could be overthrown if it didn't. Montesquieu proposed separation of powers, Voltaire called for religious toleration and freedom of speech, Rousseau's Social Contract described the general will, and Mary Wollstonecraft argued for women's education and rights. Philosophes shared ideas through salons, coffeehouses and Diderot's Encyclopédie. Deism saw God as a clockmaker who created the universe but didn't intervene.

Some monarchs, called enlightened absolutists, adopted Enlightenment reforms while keeping full power. Frederick the Great of Prussia promoted religious toleration and education, Joseph II of Austria abolished serfdom, and Catherine the Great of Russia corresponded with philosophes but strengthened serfdom after Pugachev's rebellion. Adam Smith's Wealth of Nations (1776) criticized mercantilism and argued for free markets. Economic changes, including consumer goods like coffee and sugar, the growth of a middle class and the cottage industry, set the stage for industrialization.

Cesare Beccaria's On Crimes and Punishments (1764) argued against torture and the death penalty and for punishments that are swift, certain and proportionate to the crime. Andreas Vesalius corrected ancient anatomy through dissection, William Harvey showed that blood circulates, and Edward Jenner's smallpox vaccine (1796) later advanced medicine. Governments sponsored scientific societies such as England's Royal Society and the French Academy of Sciences to share and test discoveries.

Philosophes often criticized European customs indirectly, as in Montesquieu's Persian Letters, which views France through foreign eyes. Skeptics like David Hume questioned miracles and religious authority, and Kant defined Enlightenment as daring to think for oneself.

Key ideas

• The Scientific Revolution relied on observation and experiment.
• Newton described the universe as governed by natural laws.
• Enlightenment thinkers applied reason to government and society.
• Enlightened absolutists adopted some reforms while keeping power.
• Adam Smith argued for free markets over mercantilism.

Formulas and rules

Common mistakes

• Mixing up Hobbes (strong ruler needed) and Locke (government protects rights).
• Thinking enlightened absolutists gave up power; they kept absolute rule.

Words to know

Scientific Revolution

Shift to observation and experiment to understand nature.

Heliocentrism

The theory that Earth orbits the sun.

Copernicus

Astronomer who proposed a sun-centered universe.

Galileo

Scientist who used the telescope to support heliocentrism.

Isaac Newton

Scientist who described the laws of motion and gravity.

Empiricism

Gaining knowledge through observation and experience.

Francis Bacon

Promoter of the inductive, experimental method.

René Descartes

Philosopher who emphasized deductive reasoning.

Hobbes

Philosopher who argued people need a strong ruler.

Montesquieu

Philosopher who proposed separation of powers.

Voltaire

Philosophe who championed toleration and free speech.

Rousseau

Philosopher who wrote about the social contract and general will.

Mary Wollstonecraft

Writer who argued for women's rights and education.

Salon

A gathering where Enlightenment ideas were discussed.

Deism

Belief in a God who created the universe but doesn't intervene.

Enlightened absolutism

Absolute monarchs adopting Enlightenment reforms.

Sample practice questions

5 more questions like these, from level 1 to 5, are in the practice set.