Delaunay was fascinated by how the interaction of colors produces sensations of depth and movement, without reference to the natural world. In Simultaneous Contrasts that movement is the rhythm of the cosmos, for the painting's circular frame is a sign for the universe, and its flux of reds and oranges, greens and blues, is attuned to the sun and the moon, the rotation of day and night. But the star and planet, refracted by light, go undescribed in any literal way. "The breaking up of form by light creates colored planes," Delaunay said. "These colored planes are the structure of the picture, and nature is no longer a subject for description but a pretext." Indeed, he had decided to abandon "images or reality that come to corrupt the order of color."
The poet Guillaume Apollinaire christened Delaunay's style "Orphism," after Orpheus, the musician of Greek legend whose eloquence on the lyre is a mythic archetype for the power of art. The musicality of Delaunay's work lay in color, which he studied closely. In fact, he derived the phrase "Simultaneous Contrasts" from the treatise On the Law of the Simultaneous Contrast of Colors, published in 1839 by Michel-Eugène Chevreul. Absorbing Chevreul's scientific analyses, Delaunay has here gone beyond them into a mystical belief in color, its fusion into unity symbolizing the possibility for harmony in the chaos of the modern world.
from The Museum of Modern Art, MoMA Highlights, New York: The Museum of Modern Art, revised 2004, originally published 1999