AP European History Unit 4 Essentials: Key Terms & Big Ideas

CID — Cultural & Intellectual Developments

Enlightenment thinkers applied reason and empirical methods to challenge traditional political and religious authority

Building on Newton's scientific method, philosophes like Voltaire and Diderot argued that reason and observation — not tradition, revelation, or royal decree — should be the basis for understanding government, religion, and society. This intellectual confidence directly undermined the ideological foundations of absolutism and the unquestioned authority of the Church.

Newton Voltaire Reason

SP — States & Other Institutions of Power

Social contract theory provided new justifications for both limiting and exercising state power

Hobbes argued that people surrendered their rights to an absolute sovereign in exchange for order, while Locke argued that government existed only by the people's consent to protect natural rights — and could be overthrown if it failed. Montesquieu and Rousseau extended this debate, providing competing blueprints for how political power should be structured and checked.

Locke Hobbes Rousseau

ECD — Economic Development

Adam Smith's critique of mercantilism laid the groundwork for free-market economic theory

In The Wealth of Nations, Adam Smith argued that economies flourished most when individuals pursued their own self-interest in a free market guided by an "invisible hand," rather than through state-controlled mercantilist policy. This laissez-faire critique, echoed by the physiocrats, marked a major break from the economic thinking that had dominated absolutist states.

Adam Smith Laissez-Faire Physiocrats

SP — States & Other Institutions of Power

Enlightened absolutist rulers selectively adopted Enlightenment reforms while preserving centralized authority

Frederick the Great of Prussia, Catherine the Great of Russia, and Joseph II of Austria embraced legal reform, religious toleration, and patronage of the arts and sciences — but only to the extent that these changes strengthened, rather than weakened, their own centralized control. Enlightened absolutism was reform from the top down, not a transfer of power to the people.

Frederick the Great Catherine the Great Joseph II

🔍

Isaac Newton & the Scientific Revolution

Newton's Principia Mathematica (1687) synthesized earlier discoveries into a unified theory of universal gravitation, completing the Scientific Revolution and establishing the scientific method as the model for acquiring reliable knowledge.

Science

John Locke & Natural Rights

English philosopher who argued in his Two Treatises of Government that people possess natural rights to life, liberty, and property, that government exists by the consent of the governed, and that the mind begins as a tabula rasa (blank slate) shaped by experience.

Political Theory

Thomas Hobbes & Leviathan

English philosopher whose Leviathan (1651) argued that life in the state of nature was "nasty, brutish, and short," so people rationally surrendered their rights to an absolute sovereign in exchange for order and security — a pessimistic alternative to Locke's social contract.

Political Theory

Voltaire

French philosophe famous for his sharp satire and his advocacy of religious tolerance, freedom of speech, and separation of church and state, frequently criticizing the corruption and intolerance of the Catholic Church.

Enlightenment

Montesquieu & Separation of Powers

French philosophe whose The Spirit of the Laws (1748) argued that government power should be divided among separate legislative, executive, and judicial branches to prevent tyranny — a model that directly influenced later constitutional governments.

Political Theory

Jean-Jacques Rousseau & the General Will

Philosophe whose The Social Contract (1762) argued that legitimate political authority rests on the "general will" of the people, and that true freedom means submitting to laws a community has collectively chosen for itself.

Political Theory

Denis Diderot & the Encyclopédie

French philosophe who edited the Encyclopédie, a massive multi-volume compilation of Enlightenment knowledge on science, politics, and the arts, designed to spread reason and challenge traditional authority across Europe.

Print Culture

Salons & the Republic of Letters

Salons hosted by wealthy, often female patrons brought philosophes together to debate new ideas, while a transnational "Republic of Letters" of pamphlets, journals, and correspondence spread Enlightenment thought across national borders.

Print Culture

Enlightened Absolutism

A pattern of rule in which monarchs such as Frederick the Great of Prussia, Catherine the Great of Russia, and Joseph II of Austria adopted Enlightenment-inspired reforms — legal codification, religious toleration, support for the arts — while still preserving centralized, autocratic power.

Politics

Adam Smith & Laissez-Faire

Scottish economist whose The Wealth of Nations (1776) argued that free markets, driven by individual self-interest and an "invisible hand," generate more wealth than state-controlled mercantilist policy — the founding text of modern free-market economics.

Economics

Physiocrats

A group of French economic thinkers who argued that land and agriculture, not gold or trade, were the true source of national wealth, and who favored minimal government interference in the economy — an important precursor to Adam Smith's laissez-faire theory.

Economics

Deism & Religious Skepticism

Many Enlightenment thinkers adopted deism, the belief in a distant, rational creator-God who set natural laws in motion but does not intervene in human affairs, reflecting growing skepticism toward traditional, revelation-based religious authority.

Religion