Niccolò Machiavelli (Florence, 1469–1527), best known for his "Il Principe" was the founder of realist political philosophy, advocated republican government, citizen armies, protection of personal property, and restraint of government expenditure as being necessary to the liberties of a republic. He wrote extensively on the need for individual initiative—"virtu"—as an essential characteristic of stable government. He argued that liberty was the central good which government should protect, and that "good people" would make good laws, whereas people who had lost their virtue could maintain their liberties only with difficulty. His Discourses on Livy outlined realism as the central idea of political study and favored "Republics" over "Principalities".