The constitution has divided the powers of government into three branches, Legislative, Executive and Judiciary, lodging each with a distinct magistracy. The Legislative it has given completely to the Senate and House of Representatives. It has declared that the Executive powers shall be vested in the President, submitting special articles of it to a negative by the Senate, and it has vested the Judiciary power in the courts of justice, with certain exceptions also in favor of the Senate.
Thomas Jefferson, Henry Augustine Washington (1859). “The Writings of Thomas Jefferson: Correspondence. Reports and opinions while secretary of state”, p.465