Spend any time in conservative intellectual circles these days and you’ll likely encounter the curious political philosophy known as “integralism”—the doctrine that all legitimate political power must be exercised under the auspices of the Roman Catholic Church. The integralists’ emergence, on Twitter and in magazines ranging from the Atlantic to First Things, has provoked indignation from those of a more liberal-democratic bent. Integralists—including Harvard Law School’s Adrian Vermeule, defender of the administrative state and bête noir of constitutional originalists—have been happy to respond in kind.

Thomas Crean and Alan Fimister’s new book, Integralism: A Manual of Political Philosophy, is a manifesto of sorts for the movement, with little time for engagement with competing perspectives or contrary views. There is no scholastic disputatio here, but rather a complex series of claims posited with transcendental confidence.

Father Crean—a friar of the English Province of the Order of Preachers—and Fimister—assistant professor of theology at Saint John Vianney Theological Seminary in Denver—begin by arguing that the city, understood as a collection of families, is the natural political community. The city is properly ordered toward the common good rather than private interests.