Original: Montesquieu's philosophy that "government should be set up so that no man need be afraid of another" reminded Madison and others that a free and stable foundation for their new national government required a clearly defined and balanced separation of powers.
Simplified: It was Montesquieu's philosophy that "government should be set up so that no man need be afraid of another" that prompted the creators of the Constitution to divide the U.S. government into three separate branches.