"Between 1964 and 1966 Willem de Kooning painted a series of female figures on hollow-core wood doors, which were later exhibited at the Whitney Museum of American Art, March 14 through May 26, 1996. The doors which de Kooning used as painting surfaces had previously been installed in his studio, however the artist was dissatisfied with them and had them replaced with sturdier doors. After the hollow-core doors had been stored in his studio for years, de Kooning decided to paint on them. The resulting works were called the Door Cycle.
Using a door – an object charged with metaphoric values – as a painting surface seemed particularly appropriate as its measurements correspond with the human size; at the same time its appearance and dimensions represent a painter's canvas. Thinking about these formal and poetic qualities of a door, Before The Law by Franz Kafka came to mind, also works by Marcel Duchamp (door of Etant donnes, 1948-50) and Joseph Beuys (Door, 1854/56).
With its flat, empty surface, light weight and painting-size, the mass-produced door panel seemed to be an appropriate contemporary product to make work in editions with. After two years of consideration, Edition Schellmann invited a group of artists to create works of art on prefabricated hollow-core doors. The 16 works that resulted – painting, object, silkscreen, sculpture, relief, and other techniques, on wood, glass, steel and even paper – were produced in editions of 15."
- Jörg Schellmann ed., Forty Are Better Than One, Munich/New York, 2009, p. 406
"In his [Kapoor's] objects and forms the border between painting and sculpture becomes blurred. In the creation of three-dimensional bodies his way of working is typical of the sculptor, but his themes - emptiness, absence, transformation and immateriality - derive from painting. Kapoor's intention is to create sculptures that don't just deal with questions of form but also address the themes of belief, passion or experiences beyond material concerns."
- Jörg Schellmann, ed., Forty Are Better Than One, Munich/New York, 2009, p. 180