In 1929, Walter Lippmann published “A Preface to Morals.” I have forgotten to whom I loaned my copy, but there is one phrase from that work that I committed to memory the moment I read it. Lippmann wrote of the “acids of modernity” which eroded not only belief, but the disposition to believe. He went on, unsuccessfully, to ground a new basis for morals seeing as the older, more traditional sources of moral authority had fallen into disrepute, holding out the hope of “disinterestedness” as the basis of his moral vision. Of course, you can see the problem immediately: Lippmann’s disinterestedness is not only a little thin as an organizing principle, why should we be disinterested in ascertaining the ultimate meaning of human existence? Indeed, should we not be...