The cosmopolitan political tradition in Western thought begins with the Greek Cynic Diogenes, who, when asked where he came from, said he was a citizen of the world. Rather than declare his lineage, social class, or gender, he defined himself as a human being, implicitly asserting the equal worth of all human beings.

Martha Nussbaum pursues this "noble but flawed" vision and confronts its inherent tensions. The insight that politics ought to treat human beings both as equal and as having a worth beyond price is responsible for much that is fine in the modern Western political imagination. Yet given the global prevalence of material want, the conflicting beliefs of a pluralistic society, and the challenge of mass migration and asylum seekers, what political principles should we endorse? The Cosmopolitan Tradition urges us to focus on the humanity we share rather than on what divides us.