Ideas shape the world we live in—from why we get married, to what we believe will happen after we die, to why we support a particular political party, to what we believe will make us more prosperous. These ideas have histories. What we believe is not the same as what other people in other places and other times have believed. Why is this the case? Why have some ways of knowing come to dominate in some periods and places, and not in others? Why have certain notions about politics, economics, culture, and the natural world pushed aside competing claims? What roles have intellectuals played in creating and disseminating important ideas? How do particular frames of reference shape our understandings of history? What is the relationship between material conditions and the development of a robust intellectual culture? There are many ways to approach the history of ideas, ideologies, and intellectuals. Yale’s history department offers courses that focus on the history of philosophy, science, religion, and political and economic thought, as well as broader social ideas. Some courses focus on intellectuals and the development of particular schools of thought; others seek to put the realm of ideas into a range of social, economic or political contexts. Yale undergraduates can select from a range of courses focusing on ideas from the ancient to the contemporary, and from China to the Americas.