If Updike is the narrator-as-preacher, nudging his readers to speculate about what it all means, and Nabokov is the narrator-as-aesthete, insisting that his readers pay close attention to his exquisitely detailed observations, Bellow is the narrator-as-taxi driver, telling his readers to cut the nonsense and stop taking this or that fashionable idea seriously. Even though some of his novels are in the third person and others are in the first, it does not seem to make much of a difference; we hear Bellow talking in all of them, hear the voice of a writer who is in turn amused, exasperated, and angered by the way we live now.

As a worldly-wise taxi driver—one, moreover, who has read all the Great Books—Bellow is not afraid to pursue his own reflections while the plot languishes. He is our most essayistic novelist; his main characters are always struggling with...