Knowing the past is as astonishing a performance as knowing the stars. Astronomers look only at old light. There is no other light for them to look at. This old light of dead or distant stars was emitted long ago and it reaches us only in the present… Hence astronomers and historians have this in common: both are concerned with appearances noted in the present but occurring in the past. The analogies between stars and works of art can profitably be pursued. However fragmentary its condition, any work of art is actually a portion of arrested happening, or an emanation of past time. It is a graph of an activity now stilled, but a graph made visible like an astronomical body, by a light that originated with the activity. When an important work of art has utterly disappeared by demolition and dispersal, we can still detect its perturbations upon other bodies in the field of influence.
George Kubler (1962)