There are two consequences of forming the political space as if it is a market where economic demands are met. First, justice is abstracted from its moral context and confined to distribution, rights, taxation, actors, and entitlement. Second, the relationship between authority and citizens is reduced to voting and benefiting from public services. The source of the problems such as populism, propaganda, manipulation, violence, relativism, post-truth, value pluralism and skepticism that political philosophers are currently trying to analyze and solve is the transformation of politics into a market place. Being aware of these problems of contemporary political philosophy, Mary M. Keys published her book, Aquinas, Aristotle and the Promise of the Common Good, to reconcile the obvious contradiction between the individual good and the common good of the community, and to bring politics and morality together on the normative and universal level, and then to offer solutions to the contemporary problems of political philosophy. Having presented comparatively the role of the common good in the thought system of Aristotle and Aquinas, she lays a bridge between the medieval philosophy and contemporary political thought by suggesting the possible contributions of the common good to political philosophy. What makes this book unique is that it brings together political philosophy, ethics and theology in the context of the common good.