Karen Vaughn, who played a pivotal role in building the economics program at George Mason University, made important—though underappreciated—contributions to the history of economic thought, subjectivist economic methodology, thinking about social change and learning, and the political economy of morality. Among her key insights was that constitutional orders will be greatly shaped by moral attitudes and commitments. The maintenance of a free society may require restraining our impulses to use politics to eliminate all imperfections.