We tend to speak of a ruin as a building that has failed, but the eighteenth-century taste for ruins suggests the opposite: a structure that has, in a sense, succeeded at last. A cathedral in use is a machine for a single purpose — worship — and it bends every arch to that end. Let the roof fall, the congregation scatter, the ivy in, and the same stones are released into a second life as pure form, available to the wanderer's eye rather than the worshipper's knee. The Romantics who sketched broken abbeys were not mourning; they were, if anything, congratulating time for finishing what the architect had only begun. This is a perverse doctrine, and I state it in its strongest form precisely because I mean to argue against it. A building emptied of its use is not liberated into art. It is merely misheard by those who never needed it to work.