Xenophon's Socrates also has different philosophical positions from Plato's Socrates, such as his interpretations of Socrates' belief that virtue is knowledge: Xenophon's Socrates is more practical and defends his own views more often than Plato's Socrates. But by and large, both Plato and Xenophon characterize Socrates as the great mind who criticized the Athenian social and political system.