ABSTRACT

A wide range of materials which convey information visually are used as part of the education process, and at no other time has it been possible to take advantage of a rich variety of visual experience and knowledge with so much ease; photography and electronic processes are widely available. The history of ideas about vision is in the development of human thought, within which we can identify two contrasting approaches. The classical tradition, in separating vision from thinking, generated the idea of a ‘mind’s eye’ which looked at the retinal image. The problem was that were left with the need to explain the way the mind’s eye worked and so on in an endless regress. If the image is stabilised under experimental conditions the retinal cells become satiated and the object on which the eye is focused appears to merge or disappear into the background.