Cleaning is mysterious, since it is the labor that erases itself if it is successful.
Jeff Wall

When considered from the point of view of conservation, cleaning is not just a matter of practical maintenance, but an epistemological pursuit. The practice of cleaning occupies a central place in conservation literature, where it often stands as a synonym of discovery. Cesare Brandi, Italy’s most prominent twentieth-century conservation theorist, conceived of occasions to clear aside dirt as opportunities to lay bare and expand the types of knowledge that define conservation. To him, the cleaning of paintings and buildings offered chances to ask questions about the authenticity of works of art, the expressive intentions of the original creators, and about the nature of aesthetic integrity.