Abstracts, patterns and contexts

How much context do you have to remove to turn something representational into something abstract? How much depends on the viewer's perception? Some line combinations are irredeemably letters in some cultures but meaningless in others. I spent this morning photographing faded - almost invisible - words painted on a road and wondering whether the images taken from angles where they were indecipherable were abstract. Picasso could turn four lines into a torso. Some of Georgia O'Keeffe's abstracts become landscapes when near some of her other paintings.

This is an empty swimming pool with most of its context gone. Is it an abstract? If the leaves in my extra had fallen a different way would they be abstract rather than a lizard?