Editors' Note: This article is part of the Public Square 2014 Summer Series: Conversations on Religious Trends. Read other perspectives from the Catholic community here.

Part 1 of my reflections on the new working document for the 2015 synod on the family focused on its pastoral emphasis, its "accent on mercy." In this next reflection I'd like to pay attention to how it reveals a foundational Catholic understanding of love and human relationships.

The document points to the concept of Natural Law, today an often misunderstood and highly controversial idea. Its authors observe that many find the concept "highly problematic, if not completely incomprehensible" (21) and even "an outdated legacy" (22). Nevertheless, its import for writings on marriage since antiquity has been incontrovertible. In its most simple form, it refers to the way that the Creator has made creation; the rules inherent in that creation; and the way that human beings, as rational creatures, can discern the structure of reality. Astrophysicists studying quarks, paleontologists studying dinosaur fossils, neuropsychologists studying the limbic system, historians studying the causes of World War I, and theologians asking questions about the discernment of desire are all iterations of belief in some form of Natural Law. To put it differently, another name for Natural Law is "reality," and in order to understand it, one must take a long, loving look.

The neuralgic question in the contemporary world—East or West, North or South—is not whether there is a Natural Law. The question is what constitutes it. Few today really want to argue that there is absolutely no structure to reality, no underlying truth about the world and the people in it. In the arena of sexuality, for example, the evidence is far too strong to hold that all things related to sex are fabricated by society. Such a position would undercut not only arguments for conservative positions on marriage and family, but also liberal positions on the rights of women, rape and incest, sexual trafficking, even consumerism. Some theory of Natural Law is necessary if there is ever to be a decent theory of justice that is more than an expression of a will to power. Citing a paper from the International Theological Commission, the document suggests,

The natural law responds thus to the need to found human rights on reason and makes possible an intercultural and interreligious dialogue. (20)

Indeed, some of the most compelling iterations of Natural Law over the past century have come in such forums as the Nuremberg Trials following World War II and the Universal Declaration of Human Rights, both of which sought to ground notions of human rights on something that transcends limited historical, cultural expressions. The Church does not claim an exclusive apprehension of the Natural Law; its foundation of universities in the Middle Ages rather testified to a deep belief that all human beings had access to it through the right application of reason.