Read Book VI of Aristotle's Nicomachean Ethics.
In Book II, you learned that Aristotle divides virtue into two sorts that correspond to the rational and non-rational parts of the soul. The rational part is that which has reason within itself or is reason "through-and-through", while the non-rational part is capable of being influenced by reason. Book VI of the Ethics first addresses the non-rational part of the soul, which is integral to Book X and the transition made from the Ethics to Aristotle's Politics. Here, we first address the intellectual virtues applied to the non-rational parts of the soul in Book VI, or the virtues of thought associated with our emotions, feelings, dispositions, and actions, before turning to Book X.