We have a friend who each winter, as snow falls gently over the meadows of Brandenburg, heads out into the countryside for, as she nicely puts it, “a day of art.” Her art is simple: tracks made in the snow in carefully interconnected patterns. She moves as the mood takes her, but each perfectly executed spiral is linked by a delicate ribbon of footsteps to the next such spiral. Those who pass near might wonder at a woman seemingly walking in circles in a snowy field, and few ever appreciate her intent. It is only those in low-flying planes who could see the patterns inscribed on the Brandenburg landscape, and within a few days they have usually disappeared, either being obscured by new snow or fading to nothing in a thaw.

This is art at its most private and transient. Most of the intricate patterns thus made are seen by noone.