This course introduces students to the study of philosophy and to the understanding that ancient, Christian, and modern philosophers offer fundamentally different answers to important questions such as Who am I? and What is happiness? It takes seriously that people of every age seek the truth, and that it is “no accident that, when the sacred author comes to describe the wise man, he portrays him as one who loves and seeks the truth . . .” (Fides et Ratio). Part I provides an introduction to principles of classical philosophy in selections from Plato and Aristotle; Part II, an introduction to Christian teachings in selections from Aquinas; and Part III, an introduction to scientific method and behaviorism in selections from Descartes and Hume, and to nihilism, relativism, and historicism in selections from Nietzsche.