When you break down the sense of sight to its most basic function, you find that it only works because of contrasts. Simple creatures with simple eyes see only extreme areas of light and dark. More developed eyes see contrasts in color as well, and can break down light and dark into more complex gradations, creating a deeper understanding of the environment outside of the body.
Whats beginning to emerge on this canvas is a study in light and dark. Simple contrasts that form a perception of reality. I'm studying the light as well as the shade here. The two together will weave a tapestry of highs and lows like interlocking fingers in two joined hands.