It has always been understood that the central claim of Christianity--that Jesus born of Mary is the Son of God--is as much a declaration of the mystery of the human as it is the mystery of God; just as the claim that in virtue of this identity he is the Christ who restores, and more, transforms, the created order, intensifies the mystery of the human even further. When the age of revolution was followed by the age of science, and the effort to shape the environment by technology was joined by an injunction to shape societies and economies, and class conflicts became part of world conflicts,...