With meticulously researched and tightly argued responses to every major counterargument, What Is Marriage? is an indispensable contribution to the most pressing cultural question of our time. Until very recently, the institution of marriage was universally understood as a union between a man and a woman. The authors of What Is Marriage? delve into the reasons behind this long-standing consensus and argue that redefining civil marriage to encompass anything other than the union of a husband and wife is a misguided endeavor. Initially published in the Harvard Journal of Law and Public Policy, this book's central argument swiftly rose to become the most widely read and debated essay of the year on the premier scholarly network in the social sciences. Since its publication, scholars and activists worldwide have referenced and contested it as the most formidable defense of the traditional definition of marriage ever written. Now, in its revamped, expanded, and enhanced form, What Is Marriage? is poised to make a profound impact on the ongoing conversation. Sherif Girgis, Ryan T. Anderson, and Robert P. George present a compelling critique of the notion that equality necessitates redefining marriage, emphasizing the need for both sides to first define what marriage truly is. They argue that marriage, as a holistic union of mind and body oriented towards family life, is inherently a union between a man and a woman, and demonstrate the social benefits of enshrining this principle in law. Most notably, they illustrate that recognizing same-sex civil marriage would logically lead to the recognition of every relationship describable in polite language, including polyamorous unions, thereby further eroding the norms of marriage and the common good. Finally, the authors provide meticulous and well-reasoned responses to common objections, including claims that the traditional view is rooted in bigotry, that it disregards people's needs, and that it is an unreasoned religious perspective. With its comprehensive and tightly argued responses to every major counterargument, What Is Marriage? is an indispensable contribution to the most pressing cultural debate of our time.