Both as cardinal and as Pope Benedict XVI, one of Josef Ratzinger’s consistent concerns has been the foundational moral imperatives of the natural law. In 2004, then Cardinal Ratzinger requested that the University of Notre Dame study the complex issues embedded in discussions about “natural rights” and “natural law” in the context of Catholic thinking. To that end, Alasdair MacIntyre provided a substantive essay on the foundational problem of moral disagreements concerning natural law, and eight scholars were invited to respond to MacIntyre’s essay, either by addressing his work directly or by amplifying his argument along other yet similar paths. The contributors to this volume are theologians, philosophers, civil and canon lawyers, and political scientists, who reflect on these issues from different disciplinary perspectives. Once the contributors’ essays were completed, MacIntyre responded with a closing essay. Throughout the book, the contributors ask: Can a persuasive case for a foundational morality be made etsi Deus daretur (as if God did not exist)? And, of course, persuasive to whom? The exchanges that take place between MacIntyre and his interlocutors result, not in answers, but in rigorous attempts at clarification. Intractable Disputes about the Natural Law will interest ethicists, moral theologians, and students and scholars of moral philosophy.