Like globalist, cosmopolitan has become a freighted term, not least for its anti-Semitic undertones. On the right, it is an epithet for bleeding-heart liberals who support looser immigration policies, foreign aid, and multilateral efforts to confront climate change. On the left (and the nativist right), it is used to describe the Davos crowd and footloose capitalists. But as the philosopher Martha C. Nussbaum reminds us in The Cosmopolitan Tradition, cosmopolitanism has a rich history as a mode of political and ethical thought, one that “urges us to recognize the equal, and unconditional, worth of all human beings.”
The cosmopolitan tradition has its roots in the fourth century BCE, when Diogenes the Cynic declared himself a “citizen of the world” (kosmopolitês), and insisted on the dignity of all people, no matter their origin or rank. His example would go on to inform Greek and Roman Stoicism, conceptions of international and natural law and human rights, and much else in Western political philosophy. Yet as Nussbaum shows, cosmopolitanism, owing to its origins, has always been vulnerable to a critique from within. “Precisely because they are so determined to insist that the basis for moral duties is never effaced by life’s contingencies and hierarchies,” she writes, many exponents of cosmopolitanism refuse to acknowledge the extent to which penury can limit one’s capacity to exercise individual agency, moral or otherwise. As a result, to this day, cosmopolitanism—be it in the form of trade and capital market liberalization, the contemporary human-rights regime, or liberal internationalism—tends to make insufficient provision for the amelioration of poverty, inequality, malnutrition, and other socioeconomic deficiencies.
Nussbaum’s journey through the cosmopolitan tradition begins with Cicero, particularly his final treatise, De Officiis (On Duties), which she regards as a foundational contribution to the Western tradition of political philosophy. In that work, Cicero makes a distinction between “duties of justice,” which he sees as strict and universal, and “duties of material aid,” which are far more discretionary. In practical terms, duties of justice oblige us to prevent, punish, or otherwise object to crimes such as torture, rape, and murder wherever they occur; that is, we must not only avoid such unjust acts, but also intervene to prevent them if we are able. Duties of material aid imply merely that there are instances when we should extend assistance to the needy, but with a preference for those in our own family, tribe, or nation.