The central theme is belief in miracles, especially miracles concerned with healing the body of disease or illness. Contrasting epigraphs open the novel and frame the debate: "They say miracles are past" (William Shakespeare) and "The Age of Miracles is forever here!" (Thomas Carlyle). On one side are those who think that miracles are illusions which cannot stand the scrutiny of modern science or delusions which reflect the self-deception, desperation, and naivete of the believer. On the other side are those who accept illogical or unpredictable improvement in health as evidence of divine intervention. The novel describes many people seeking a miracle; one occurs that is unexpected, known only to a few and completely unexplained.