Western political philosophy originates in the philosophy of ancient Greece, where political philosophy dates back to at least Plato. Ancient Greece was dominated by city-states, which experimented with various forms of political organization, grouped by Plato into four categories: timocracy, tyranny, democracy and oligarchy. One of the first, extremely important classical works of political philosophy is Plato's Republic, which was followed by Aristotle's Nichomachean Ethics and Politics. Roman political philosophy was influenced by the Stoics, including the Roman statesman Cicero.