Student of Plato, tutor of Alexander the Great, founder of the Athenian Lyceum, Aristotle possessed a pedigree every bit as singular as his influence would prove to be. His ideas, instruments of investigation, and observations of nature both loom over and underlie much intellectual endeavor. His works had profound authority for medieval thinkers from Muslim mathematicians to Catholic scholastics such as Thomas Aquinas. To be honest, it’s not much fun to turn his pages. Whereras Plato is a pleasure to read, Aristotle is a chore. This is in large part because most of the texts that have come down to us are in fact Aristotle’s notes for the lectures he delivered in the Lyceum. Still, it’s well worth encountering Aristotle’s thinking at its source, and the best place is the Nicomachean Ethics, in which he asks what makes people happy and offers instruction on living a successful life. You might even go directly to books 2 through 5 in order to concentrate on the Aristotelian idea of the behavioral golden mean—the need to conduct oneself between extremes—and the philosopher’s annotated catalog of the necessary moral virtues—courage, temperance, generosity, magnanimity, gentleness, friendliness, truthfulness, charm—and how best to measure them in our own behavior.