As a young American in Paris in 1949 — four years out of the Army and one year out of a Boston art school — Ellsworth Kelly had an epiphany. The key to creative inspiration was in the world around him, not in other artists' studios or at the Louvre. If he paid close attention to, say, the contour of a window, the shape of a leaf, the play of light and shadows on man-made and natural forms, his art would emerge.