A simple geometrical model is presented, which explains the recent two-color projections of Edwin H. Land (Proc. Natl. Acad. Sci.,45, 115, 636, 1959), as well as the classical color mixing experiments. The model leads to a set of transformations similar to the Lorentz transformations of special relativity. This suggests that color is essentially a relative phenomenon. The experimental justifications of the model and the relation of its underlying postulates to the theory of evolution are discussed. Various consequences with regard to contrast enhancement, aperture colors and two-color projections are presented. A discussion of the related previous work is given and some implications for a possible neurophysiological process are indicated.