Footprints are evidence that someone has passed this way, memories stamped on ear th or pavement. They conjure images of those who might have left them; groups of footprints can seem to populate a place. Artists and activists have invoked them, as when painted purple footprints appeared throughout New York City in the 1980s to protest the government’s destruction of a beautiful garden built by the artist Adam Purple.
Our project, instead of adding footprints to the streetscape, subtracts them, using reverse graffiti—a process of writing or drawing by removing dirt from a surface, typically with pressurized water. The process cleans the surface without harming it. (Since it uses no chemicals, pigments or solvents, it also does no harm to the environment.) The images it creates are temporary, and inevitably succumb to urban grime.
A subtracted footprint does not pretend to be the mark of a passing man. If anything, it is the absence of that mark, rendered in nothing—an image less of memory than of forgetting. As it fades, this image of forgetting is itself forgotten.