“The nature of our epoch,” he [Hofmannsthal] wrote in 1905, “is multiplicity and indeterminacy. It can rest only on das Gleitende [the slipping, the sliding].” He added that “what other generations believed to be firm is in fact das Gleitende.” Could there be a better description about the way the Newtonian world was slipping after Maxwell's and Planck's discoveries? “Everything fell into parts,” Hofmannsthal wrote, “the parts again into more parts, and nothing allowed itself to be embraced by concepts any more.”