How is it that we are capable of transcendent kindness—and unspeakable cruelty? How do we explain people’s strongly held opinions about abortion, gay marriage, affirmative action, eating meat, and torture? How do evolution, culture, and religion conspire to shape our moral natures? These are among the most important—and exciting—questions around, and they are the focus of this course. We will explore the modern psychological science of moral belief and action from a range of sub-disciplines, including social-personality psychology, cognitive neuroscience, and developmental psychology. We will look at research from the lab, from the community, and from the battlefield; we will discuss babies, monkeys, and psychopaths; we will debate claims about moral differences between men and women, liberals and conservatives, Christians and Muslims. We will explore issues such as prejudice and bigotry, sexuality and purity, and punishment, revenge, and forgiveness.