At First Things today, I review The Church of Saint Thomas Paine, a new history of 19th-century American rationalists. The book offers interesting and sometimes amusing portraits of these men and women, one of whom turns out to be my great-granduncle, M.M. Mangasarian (left), who founded his own rationalist congregation in Chicago in 1900. Mangasarian had initial (and unusual) success, but his “Independent Religious Society” ultimately failed, for the same reason all the rationalist societies failed: an inability to resolve basic incoherencies in the movement. Plus, the religion of science is a hard sell for Americans, who tend to believe in transcendent reality, even if they are skeptical of organized religion.

Here’s an excerpt:

Inspired by the French positivist Auguste Comte and the American transcendentalist Ralph Waldo Emerson, and taking the eighteenth-century freethinker Thomas Paine as a kind of patron saint, a small group of Americans attempted to found a rationalist “religion” with science as its highest authority. They started congregations in cities like New York, Chicago, and Portland; they held meetings on Sunday mornings to compete with Christian rivals; they even wrote catechisms and ran Sunday Schools to indoctrinate new members. All confidently believed they were the vanguard of a new, secular religion that would displace Christianity and promote human progress.

But the new religion failed. The congregations attracted few followers; typically, as one British humorist wrote, these were churches “of three persons, but no God.” Most fizzled out or merged with larger groups like the Unitarians. Other than cranks who seemed as credulous as the believers they mocked, Americans had little interest in Comte’s wedding and funeral ceremonies or the relics of secular saints. (In 1905, after a long quest, a small group of freethinkers placed something they claimed to be a piece of Thomas Paine’s brain, sold to them for five pounds by an obscure London bookseller, in a monument in New Rochelle.)

Schmidt shows that rationalist congregations failed because organizers never resolved basic inconsistencies. Rationalism valued science and rejected metaphysics. Why, then, collect relics and meet weekly for thinly disguised worship services? Moreover, rationalism “made intellectual independence and the displacement of all religious authorities foundational to its platform.” Paine himself had railed against organized religion, famously declaring, “my own mind is my own church.” Similarly, although Emerson had prophesied a new religion with “science” for its “symbol,” he insisted on individual spiritual autonomy: “I go for Churches of one.” What, then, was the point of joining a new religion, even a rationalist one? People who share only a commitment to radical individualism and an opposition to religious orthodoxy are unlikely to form an enduring community.

You can read the whole review here.