"In any picture of real excellence there must be a ghost; and such a picture, having a will of its own, may refuse to be separated from the person who gave it life, or even from its rightful owner. There are many stories to prove that really great pictures have souls. It is well known that some sparrows, painted upon a sliding screen by Hogen Yenshin, once flew away, leaving blank the spaces which they had occupied upon the surface. Also it is well known that a horse, painted upon a certain kakemono, used to go out at night to eat grass."
-Lafcadio Hearn, A Japanese Miscellany