Tamar Gendler opens her Yale course on human nature by laying out its interdisciplinary approach, drawing on philosophy, psychology, behavioral economics, and literature. She previews the course's three main strands, happiness and flourishing, morality, and political philosophy, and illustrates the kind of questions ahead with three worked examples: Plato's Ring of Gyges and whether people would act morally if invisible, the trolley problem and its variants on when it is permissible to cause harm, and the psychology of procrastination as a case of acting against one's own interest. She closes by explaining what sets this course apart from a standard philosophy survey: treating empirical findings about how people actually think and behave as evidence relevant to philosophical argument, not just as illustration.