Die Kunst ist zwar nicht das Brot, aber der Wein des Lebens (Jean Paul)
I have tried to find a good English translation of this quote, but although I found a great number of Jean Paul quotes in English, I didn't find one of this particular one. It means something like "Art may not be life's bread but it is its wine". Well, I think you get the meaning.
My painting teacher had this quote, scribbled on a piece of paper, stucked on to the wall for ages. Didn't see it today, but it might just be behind some other stuff on the wall :-).
Texture by Shadowhouse Creations.