Abstract
Newton began his optical studies believing in the modification theory, which was still universally accepted at that time, and in the perception of colour as a physiological process—a process in which the eye responds differently to the different velocities of identical globules. His discovery that white light is heterogeneous led him to switch to considering colour in purely physical terms.A century later, Goethe started out by accepting Newton's physical theory. He soon abandoned it, however, finding modification to be more in keeping with his own insights. One beneficial consequence of this was that he developed an awareness of the importance of the physiological aspect of colour perception, and was therefore able to demonstrate that Newton's theory of light and colours is too simplistic; that there is more to colour than variable refrangibility