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Separation of Powers

Disciplines:
political philosophy
law/constitutional law

Summary

The constitutional doctrine, developed by Montesquieu, that political liberty requires dividing governmental power among separate institutions (legislative, executive, judicial) so each can check the others.

Core Contribution

Against concentrated power: Montesquieu's observation of the English constitution (somewhat idealized) — power is divided; tyranny arises when it is concentrated. Three branches: legislative (makes law), executive (implements law), judicial (interprets law). Checks and balances: each branch has tools to limit the others. The American Founders — particularly Madison — adopted and extended the principle. The Federalist No. 51: 'Ambition must be made to counteract ambition.' One of the foundational principles of liberal constitutionalism.

Historical Influences

Locke Roman Republic

Intellectual Lineage

Republicanism Natural Law Theory

Allied Works

The Spirit of the Laws Federalist No. 51Constitutional Government and Democracy

Contemporaries & Peers

Popular Sovereignty Absolute Sovereignty

Minds Influenced

US Constitution Modern Constitutional DesignAdministrative Law

Intellectual Posterity

Constitutional Democracy Administrative Law International Law

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