Unity

Unity implies that if you clipped out any section of a painting and positioned it anywhere else in the painting, it would still look like it came from that painting. You couldn't clip out a piece of any Rembrandt painting and put it into a Jackson Pollock drip painting and get a feeling of unity.

So what gives a work a sense of unity? A theme could be established by a unifying geometric shape. Mondrian comes to mind. A painting which is dark on one side of the canvas and high key on the other would not have a sense of commonality. But a painting which is composed of primarily dark values would have unity. A common repeated color can also give a painting the sense of relatedness and thus, unity.

In this painting of a wharf scene, the same colors can be found all over the page. If a bright red shape were inserted into all these pastels, unity would be destroyed.