Answer
Greek and Roman philosophies have been the primary focus of Nussbaum's work. She has extensively studied the ethical and political thought of ancient Greek philosophers such as Socrates, Plato, and Aristotle, as well as Roman Stoics like Seneca and Epictetus. Nussbaum's research explores how these ancient philosophies can inform contemporary ethical and political debates, particularly regarding issues of justice, equality, and human flourishing.