Ultimately, there is something odd about settling in somewhere new — about the perhaps laborious process of getting used to new surroundings and fitting in, a task we undertake almost for its own sake and with the definite intention of abandoning the place again as soon as is it is accomplished, or shortly thereafter, and returning to our previous state. We insert that sort of thing into the mainstream of our lives as a kind of interruption or interlude, for the purpose of "recreation," which is to say: a refreshing, revitalizing exercise of the organism, because it was in immediate danger of overindulging itself in the uninterrupted monotony of daily life, of languishing and growing indifferent. [...] What people call boredom is actually an abnormal compression of time caused by monotony — uninterrupted uniformity can shrink large spaces of time until the heart falters, terrified to death. When one day is like every other, then all days are like one, and perfect homogeneity would make the longest life seem very short, as if it had flown by in a twinkling. Habit arises when our sense of time falls asleep, or at least, grows dull; and if the years of youth are experienced slowly, while the later years of life hurtle past at an ever-increasing speed, it must be habit that causes it. We know full well that the insertion of new habits or the changing of old ones is the only way to preserve life, to renew our sense of time, to rejuvenate, intensify, and retard our experience of time — and thereby renew our sense of life itself. That is the reason for every change of scenery and air, for a trip to the shore: the experience of a variety of refreshing episodes.
— from The Magic Mountain, by Thomas Mann.
One must remember that our hero is merely vacationing at the sanatorium. In all superficial respects he is fully integrated into the routine of the place — the meals, the rest cures (Hans is now expert at blanket tucking), the concerts, the lectures (and, by the way, he's still reading a paperbound book entitled Ocean Steamships), but some portion of his brain niggles at him, reminding him that he is to leave soon, which reminder comes mostly as a relief but seems also to be felt occasionally as a regret.
Hans seizes his last week to enjoy a flirtation with the door-slamming, sweater-wearing Madame Chauchat (who reminds him of a boy he knew at school). Presumably he feels the pressure of time running out and he would regret not taking some action, but the limits on his scheduled time here give him the excuse of indulging without responsibility, without long-term consequence, and with little embarrassment or guilt. What the hell, he's on vacation!
I'm nearing the end of chapter 4, at around page 200 of 854. Hans is anticipating leaving the mountain. What, then, could the rest of the book be about?