To achieve this, the PTCD curriculum is designed to be both philosophical and historical. Course readings range from Plato and the classical poets to contemporary political theory, literature, and U.S. Supreme Court decisions. The introductory course sequence is not a conventional survey of political theory, but introduces students to a theoretical way of thinking about politics and morality, tracking the development of Western political thought over time from its origins in ancient Greek city-state, its revival in the Florentine republic, and its coalescence into the modern liberal democratic consensus during the Enlightenment, which they can then use as a basis of comparison in analyzing the American experience. Other required "core" courses confront students with the most systematic justifications philosophers have offered for one or another conception of justice and also the most challenging, sometimes unorthodox objections to grand theories of justice, including those of Jean-Jacques Rousseau, Karl Marx, and Friedrich Nietzsche. In senior seminars, students can critically explore a focused topic in depth in such a way that many of the themes and questions that have been raised by the curriculum may be viewed in a new light. In addition, a wide range of electives, including courses on technology, religion and politics (including, recently, political Islam), the Supreme Court and African-American political thought, are available to allow students to pursue more specialized interests relevant to the general concerns of the field.