thanks nathan, i knew of the phenomia, but didn't know there were words to describe them.

the man in the moon, or the canals of mars are illusions of time and lighting.. and imagination. a form of pareidolia

but hearing music in rain drop is (well not seeing, but hearing) patterns were none in fact exist. (apophenia)

i suspect, if you get to the roots of the words, the difference is perhaps clearer..

just looking at pareidolia. is see eido in the center.. and know this root for kaleidoscopes
(a made up word form greet roots--kali a greek root word for beautiy (as in caligraphy) eido (way (process, means) and scope (seeing, being able to see) --kaleidoscopes are a beautiful way to see things. (and they are, aren't they!)

eido in pareidolia is based on the way we perceive things. NH' (now gone) old man of the mountain, only looked like an old man from a certain vantage point. a few miles back on the road, he wasn't there, a few miles further down the road, he disappeared again.

from a single point he existed.. the illusion was real
(the face in the smoke of the world trade center could be seen if you went through the footage frame by frame.. but not if you watched at normal speed--it was there..as an illusion.)

but apophenia--there is nothing there but imagination..