Piet Mondrian Composition with Red, Yellow, and Blue 1927

The greyscale version shows the yellow square to be almost equiluminant with the white space, which gives it a vibrant and quavering quality, as compared with the red and blue squares which due to their darker luminance appear more stable and grounded in their respective positions in the upper left and lower right corners. We notice that the smallest colored square, the blue, is also the darkest. Perhaps the red square needs to be bigger and longer in order to counterbalance the density of the small, dark, blue.