One French judge's book talked the American founders into splitting power three ways

In The Spirit of the Laws (1748), Montesquieu argued that liberty survives only when legislative, executive, and judicial power sit in separate hands that can check one another, since concentrating all three produces tyranny. He pointed to England's mixed constitution as his working model. His framework went on to shape the US Constitution's system of checks and balances directly.

— Montesquieu, The Spirit of the Laws — 1748
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