Busyness serves as a kind of existential reassurance, a hedge against emptiness; obviously, your life cannot possibly be silly or trivial or meaningless if you are so busy, completely booked, and in-demand every hour of the day.

It’s not as if any of us wants to live like this, any more than any one person wants to be part of a traffic jam or stadium trampling or the hierarchy of cruelty in high school — it’s something we collectively force one another to do.

Idleness is not just a vacation, an indulgence or a vice; it is as indispensable to the brain as vitamin D is to the body, and deprived of it we suffer a mental affliction as disfiguring as rickets. The space and quiet that idleness provides is a necessary condition for standing back from life an...