There are no criteria available to judge the quality of these crea-
tive expressions, because, as Wall states, aesthetic criteria are only
valid within the classic disciplines—painting, drawing, sculpture,
the graphic arts, and photography. These ‘canonical forms’ are still
thriving, by the way, in spite of all efforts by artists to subvert them
from within; but they thrive as a separate sector within contempo-
rary art, as a genre with its own laws and standards.