Who is best known for the theory of checks and balances in government?

Montesquieu is best known for the theory of checks and balances in government, which he articulated in his influential work "The Spirit of the Laws." In this text, he explored how separating governmental powers into distinct branches—namely the executive, legislative, and judicial—could prevent any single entity from becoming too powerful and thereby safeguard individual liberties. Montesquieu's ideas significantly shaped modern democratic governance and influenced the framers of the United States Constitution, who incorporated a system of checks and balances to ensure that power would be distributed and regulated among different branches of government. Thus, Montesquieu’s theories address the necessity of mutual oversight among branches to maintain a stable and fair government, establishing him as a key figure in the development of political thought regarding the separation of powers.