A Philosophically Conservative Rejoinder to What Is Marriage? What Is Marriage? Man and Woman: A Defense, authored by Ryan T. Anderson, Robert George, and Sherif Girgis, is widely recommended as the foremost defense of “one man/one woman” marriage based on natural law principles. The book has undoubtedly been influential, even to the point of being cited by Supreme Court Justice Samuel Alito in his United States v. Windsor dissent. Significantly, the book does not rely

“When the thinker thinks rightly, he follows God step by step; he does not follow his own vain fallacy.”1 Studying the Middle Ages is a complex process, not only for the plethora of information one must process in order to have a halfway-informed perspective into the period, but also for the multitude of ways in which contemporary—modern and postmodern—attitudes that illuminate Christian opinions of this important period of Christian history. One need look no further