Surrealism surged during the and art copied dreams. Fantasy and imagination were paramount, and drugs were often involved. Here is a Dali piece; Dali and Schiaparelli were friends who played off each other's ideas. “The Horseman of Death”, Salvador Dalí.
This one is entitled 'Island Dreams' by Jim Warren. It is an illusion of a different type. The roaring waters and silent grandeur seem to become a part of you, as the women's hair becomes part of the waterfall.