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
Front of the Library of Celsus with aediculae in Ephesus.
In ancient Roman religion, an aedicula (plural aediculae) is a small shrine.
Many aediculae were household shrines that held small altars or statues of the Lares and Penates, household gods guarding the entire house.
Other aediculae were small shrines within larger temples, usually set on a base, surmounted by a pediment and surrounded by columns. In ancient Roman architecture the aedicula has this representative function in the society. They are installed in public buildings like the triumphal arch, city gate, and thermae.
From the 4th century Christianization of the Roman Empire onwards such shrines, or the framework enclosing them, are often called by the Biblical term tabernacle, which becomes extended to any elaborated framework for a niche, window or picture.