Artworks present only an appearance of an appearance of what is really real.

  Plato holds in the Republic and elsewhere that the arts are representational, or mimetic (sometimes translated “imitative”). 

So Artworks are ontologically dependent on, and inferior to, ordinary physical objects, which in turn are ontologically dependent on, and inferior to, what is most real, the non-physical Forms. 

Grasped perceptually, artworks present only an appearance of an appearance of what is really real.