In Celtic lore, the phrase ‘thin place’ refers to a location where the barrier between heaven and earth is thinner than other places, meaning the glory of the heavenly realm is more easily accessed at those locations.
I’m about to steal the term for my own purposes.
I believe that true Art creates thin places between the phenomenal and noumenal realms. In my previous post on the matter I mentioned four beautiful things (sunsets, Porsches, the Taj Mahal and The Raft of The Medusa) saying that The Raft of The Medusa is the only one I would consider art. Unlike the Porsche, its purpose does not lie in the phenomenal realm. It exists to cause it’s viewers to ponder noumenal elements. It thus reunites the observer, and the phenomenal elements used to create the painting, with the noumenal.
So here is my definition of Art (as distinguished from my first category, beautiful things): created from phenomenal items (paint, words, sounds, etc) in order to reunite the observer (and the phenomenal elements themselves) with the noumenal realm.
(I say reunite, because the proper relationship between phenomenal and noumenal is unity; the world was created with no ‘thick places’. I assert they have been improperly separated, but that is for another post.)