Political theory is about ideas, including freedom, equality, and justice. Political ideas matter because we act on them; they inform our institutions of governance. They matter too because we debate our future using them; they tell us what is to be done. This course explores the ideas that inspired the world in which we live and the ideas that might direct our future. It focuses in particular on ideologies which contain ideas about what the world is like, why it is as it is, and what it might become. After a brief examination of the nature of political theory and ideology, the course looks successively at liberalism, conservatism, socialism, nationalism, feminism and environmentalism.