Enlightenment

Montesquieu

1689–1755

When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty.
The Spirit of the Laws, XI.6

Charles-Louis de Secondat, Baron de Montesquieu, was a French jurist and man of letters. classifies governments by their nature and by the principle that animates them: virtue in republics, honor in monarchies, fear in despotisms. He relates laws to climate, commerce, religion, and manners, and argues for a distribution of powers that checks arbitrary rule. The American founders read him carefully. Constitutional thought still works with his vocabulary of spirit, form, and separation of powers.

In the Conversation

15 of the Great Ideas

Ethics

Politics

Government

Liberty is preserved by the separation of powers. Government must be divided against itself.

Law

Laws must suit the spirit, climate, and character of a people. Liberty requires separation of powers.

War and Peace

War arises from the existence of separate societies, not from individual human nature.

Democracy

Democracy requires virtue as its principle, and separation of powers as its safeguard.

State

The structure of the state varies with climate, custom, and commerce; liberty requires the separation of powers.

Wealth

Commerce softens manners and binds nations in mutual dependence; the spirit of trade naturally promotes peace and moderation.

Revolution

The separation of powers prevents the concentration that breeds tyranny and revolution; moderate government is the best safeguard.

Tyranny

Despotism rules by fear without fixed laws; the separation of powers is the structural remedy against tyranny.

Citizen

Each form of government requires a different kind of citizen: the republic demands civic virtue, the monarchy honor, and despotism only fear.

Slavery

Slavery is contrary to nature and corrupts both master and slave; no argument in its favor withstands scrutiny.

Constitution

Liberty depends on the separation of legislative, executive, and judicial powers; when any two are united, freedom is lost.

Monarchy

Monarchy is government by one person according to fixed and established laws, sustained by the principle of honor.

Aristocracy

Aristocratic republics survive through moderation; the nobles must restrain themselves or destroy the state.

Oligarchy

When moderation abandons an aristocracy and wealth becomes its sole principle, the republic dies.