Settembrini enters Hans' room in the sanatorium and flicks on the ceiling lamp, "overflowing" his immaculate quarters with white light, throwing the young man's simple mind into sharp relief. Mann plays fast and loose with light's rudimentary symbolism. He calls Settembrini by the name Satana and remarks on his hissing, sibilant "s"es. He is a serpent in the midst of Eden; a corrupter (Lucifer, after all, means "light bearer"). He kindles Hans' development on the Magic Mountain—coaxing the little bourgeois out of his coat, revealing the shirt-sleeved Romantic hiding beneath; tutoring him on the toxic effects of irony and the imperatives of eros. In the rarefied Alpine air, Hans flourishes while his peers languish, their bacterial infections slowly spreading. His cousin Joachim and the blue-veined Clavdia for whom he pines, along with many others, die of tuberculosis, their corpses sent down the mountain on sleds into the village below to be buried. Death on the mountain is only magically real. Chutes and ladders. Light handles the true business of living and dying.

So much a part of Mann's cruel irony in his novel, light signifies both the imparting of knowledge and the first salvo of modern warfare. It is switched on and off, either by the human hand or by nature, and divides its time between metaphors of wisdom, love, and damnation. A lightning strike shatters the hermetic atmosphere of the mountain sanatorium and sends Hans and his fellow patients "tumbling" down the slopes, not on sleds or skis, but head over heels to finally land, seeing stars on the battlefields of World War I. As with the Greeks, heavenly violence begets earthly war. The bolt from the blue razes the mountain to its foundations and in the space of a few pages, high and low, healthy mind and sickly body, heaven and earth collapse in the heat of a thunderbolt, its self-same radical energy a purely natural conflict of positive and negative charges.  Atomic, indeed.

Charges and discharges. Responsibilities and fired shots. Archduke Ferdinand's assassination confounds even Settembrini's staunch positivist resolve, so pulled is he between his disgust of violence and his reverence for freedom, of which revolution is no small part. The enlightenment tradition Settembrini champions and whose fire tests and refines Hans' character throughout the novel becomes a nodded assent to the argument for WWI. Complicit as it is in justifying the Great War, the light borne by knowledge is not so much a lamp held against darkness as it is a torch thrown upon a pyre. Humanism, and with it, Hans' character, collapses in the face of this cataclysm.