Vera Icon. 2006. Hand embroidery on linen. 48 x 43 in. (121.9 x 109.2 cm)

I must mention here a new imaginative device, which may seem trivial, even ludicrous, but is actually very useful. Look at wall spotted with different stones: if you have to invent some setting, you may be able to see here diverse landscapes, with mountains, rivers, rocks, trees, plains, valleys, and hills; or you may see battles and figures in action; or strange faces and costumes—an endless variety of things that you can distill. So stop sometimes to look at the stains on walls, or the ashes of a fire, or clouds—you may find marvelous ideas there.

— Leonardo da Vinci, c. 1500