The chief archivist did not at first understand the appearance of these warning signs posted around the excavation of Heliopoli. One, the excavation does not allow for tourists, and guests are only admitted by special invitation of the excavators. And two, most of what has been discovered so far is hardly delicate enough to fade over time from flash photography. It must be concluded, therefore, that it is photography itself that is warned against, and the excavators are warning themselves.

The chief archivist is reminded of his trip to Italy years ago and the many photos he took, which, upon returning, he was reluctant to look at, and to this day has only occasionally glanced upon. He had already known, at least for him, how photographs become substitutes for what one remembers seeing. When one thinks back on an occasion, what one sees is the still image of the photograph of that place and time, rather than the memory.

There can be no photograph that can do justice to the lighting of the clouds as one exits St. Peter’s, the glint of sunset off the gold of the mosaic on St. Mark’s in Venice, the twilight sky as background to the blue-and-gold tie-up pole along a canal, a stained-glass dove glowing because it is made of alabaster, and Michelangelo’s Pietà.

The excavators likewise may be discovering things that they wish not to fade in memory, not to be cheapened by being reduced to a photograph, not to degrade in time by being transformed into an object.

Sometimes an empty picture frame is more desirable than a picture itself, to see with the mind’s eye.