reasoning was largely speculative, and his ideal system ended up looking a bit like modern fascism or communism. Plato's student, Aristotle, on the other hand, was the first empirical political scientist and sent out his students to gather data from the dozens of Greek city-states. With these data, he constructed his great work Politics. Both Plato and Aristotle saw Athens in decline; they attempted to understand why and to suggest how it could be avoided. They thus began a tradition that is still at the heart of political science: a search for the sources of the good, stable political system. Aristotle was not shy about identifying what worked best, as in this passage from Politics: