This lecture is devoted to an analysis of the first book of the Nicomachean Ethics. This is the proper place to begin our study of Aristotle’s political philosophy, above all because Book I offers a penetrating account of our longing for happiness, the final end of all our strivings; it speaks with great precision and great beauty of what we mean when we give voice to our deepest hope for happiness. It also offers a remarkable sketch of the serious alternatives available to us in our attempts to find happiness. The order of topics taken up in this lecture will mirror very closely the parts of Aristotle’s own argument in Book I of the Ethics. We will turn first to his introductory discussion of happiness and the good; then follow out his exploration of the meaning of the term “happiness”; and then finally explore some of the questions that Aristotle’s challenging account of happiness leaves for us to ponder, chief among them the sway that chance or fortune holds over our lives.