With elegant symmetry and a cool, genteel prose style, Ms. Li tracks these parallel stories, exploring the duo’s worldly educations and the ruthless sacrifices to love and friendship they make in pursuit of their ambitions ... The novel is so doctrinaire about its pessimism that it mostly neglects the characters’ music. The moments are rare—and therefore gratefully encountered—when John and Adelaide are permitted to take pleasure in the 'pure joy' of their playing.