ABSTRACT
Modern accounts of vision draw on the past in innumerable and often unstated ways. The distinctions we draw between the physics of light, physiological responses to light and the psychology of perception, represent the outcomes of hard-won battles. The theories applied to each of these remain matters of investigation and debate. We are in a better position to appreciate the massive advances that have been made in understanding the nature of light, image formation, visual anatomy and physiology, and visual phenomena themselves when we can place them in the context of the past. The historical perspective is often overlooked or neglected in books on perception, which is regrettable because it implies that we now have a specially privileged viewpoint, superior to those of the past. In fact, the same theoretical issues often recur, disguised by new jargon to appear different. A historical perspective serves to emphasise the continuing evolution of ideas, concepts and theories in the light of critical evaluation and experimental evidence.
