Economic historian Deirdre McCloskey observed that liberalism is the mother of the 3,000% increase in material abundance that the world has enjoyed over the past 2 1/2 centuries. Because liberalism acknowledged the dignity of the common person, it tapped humanity’s creativity, ingenuity and productive capacity, ushering in dramatically improved conditions, longer lifespans and more elbow room for economic, scientific and cultural experimentation. Liberalism shifted political control from a narrow band of autocrats and landed elites to a body of self-governing citizens. By supporting the open exchange of ideas, liberalism makes us partners in discovery and truth-seeking, which in turn pushes out the boundaries of knowledge and human progress.