The sociologist Rodney Stark’s controversial new book “Discovering God” resurrects, if you will, the notion that truths about God can be discovered through the application of reason. Let the vociferous atheists holler, he says at the outset; the marketplace of ideas is exactly like any other marketplace, and the best, most authentic ideas about God will triumph and endure. Four hundred pages later he unveils his conclusion, one that comes as no surprise to those who know Stark’s previous work. Quickly dispensing with Hinduism, Buddhism, Jainism, Taoism and Confucianism, as well as the religions of Sumer, Egypt, Greece, early Rome and Mesoamerica, Stark states that Christianity offers the most “complex and nuanced” vision of God and the most “comprehensive doctrine of salvation.” Judaism comes in second. Islam is not, as he puts it, an “inspired” faith. “I accept that Muslims will condemn this judgment,” he writes. “And of course it is merely my judgment, upon which matters of taste and faith intrude.”

Leaving aside the flaws in his rational framework (a third of Americans believe in astrology—evidence that not just the “fittest” ideas survive), as well as the disingenuousness of setting out to “prove” what he clearly already believes as a matter of faith, Stark’s retelling of the origins of the world’s great religions is fascinating and excellent. Especially resonant is his chapter on the early Roman Empire, which contains provocative parallels to our contemporary world. Romans who sought a more intimate experience of God than the bland state religion could provide were free to experiment with any number of cults and sects; these included Judaism and Christianity, but also religions devoted to the gods Cybele, Isis and Bacchus. All were ultimately viewed as threatening and disruptive to the social order, evidence that true religious pluralism is a fragile state indeed.