To build a folly is essentially to do something a second time, something at an inopportune moment. That something is always the memory of something forgotten, about which we can paradoxically say "There it is again."
Follies were misunderstood, purposeless constructions. They were often only small, extravagant gestures in a garden, easily whisking off the imagination to distant lands, a sort of time capsule built to awaken the memory and induce surprise in passers-by. They marked locations, organized secondary paths in a park, or simply predicted the arrival of better times—a demarcation, a sacred spot, a mysterious trail, a hill whose tragic rocky nature begged for a tower, a party, or the arrival of summer.
“It is demonstrably true that things cannot be other than as they are. For, everything having been made for a purpose, everything is necessarily for the best purpose.” — Professor Pangloss
I walked around with a map, penciling in X’s wherever there was a barn or shed. For the next three days, I covered four kilometers in all four directions. Living toward the outskirts of town, there are still a good many farmers in the vicinity. So it came to a considerable number of barns—sixteen altogether.
I carefully checked the condition of each of these, and from the sixteen I eliminated all those where there were houses in the immediate proximity or greenhouses alongside. I also eliminated those in which there were farm implements or chemicals or signs that they were still in active use. I didn’t imagine he’d want to burn tools or fertilizer. That left five barns.