Society, Science, and Values

`̀ Hey guy, you are trying to make blind people think sighted!'' This comment came, very recently, from a congenitally blind person in the midst of an experiment on the perception of linear perspective in tangible drawings. Blind people bring a variety of preconceptions to research on tactile perception. For the researcher, the most difficult of these biases derive from a history of people (both sighted and blind) telling blind people what they can and can not do. Another congenitally blind person also stated: `̀ I bet that you find out what blind people can't do.'' I quickly assured her that I am interested in finding out what people can do, not what they can not do. My interests are scientific: I am interested in determining if congenitally blind people have an appreciation for geometric perspective, since many people conceive of linear perspective as a purely visual phenomenon (but see Heller et al 1996). I found in earlier work that congenitally blind people did not spontaneously produce foreshortened, tangible drawings of a board at a slant. However, they quickly learned to interpret perspective drawings, even without feedback. One would not conclude that Van Gogh did not understand linear perspective, because the painting of his garret was curvilinear and `distorted' (see Heelan 1983, page 116). Heelan took this `distorted' depiction as evidence that psychological space is curved (eg Kappers and Koenderink 1999) and nonlinear. Note that Van Gogh was influenced by Japanese art, and often looked at scenes at oblique points of view. Blind people have experienced a lifetime of people (including psychologists and rehabilitation counsellors in the USA) telling them that they can not understand pictures, and that pictures are for sighted individuals. This discouragement can affect performance when a blind person is first confronted by a novel task involving pictures or drawings. I once met a blind person, more than 10 years ago, who seemed unable to produce a simple raised line on her first attempts when using a drawing kit produced for blind people. This individual was able to generate interesting drawings on another occasion, many months later, but not when first exposed to drawing. She clearly was convinced that she could not produce drawings, and this mistaken belief prevented her from even trying to do so. Gregory and Wallace (1963) have described the frustration experienced by a congenitally blind person upon the restoration of sight. At least part of the emotional distress this person experienced was probably due to the difficulties involved in making new adjustments to society. Unfortunately, many educated blind people (in the USA) have had little exposure to tangible drawings. Most congenitally blind people have suffered a form of `benign neglect' ... they were denied contact with pictures, on the assumption that it was a waste of valuable resources to try to teach them something that is dependent upon vision or visual experience. Unfortunately, educators of blind people do not know this for certain, but merely assume it, without empirical data. The unfortunate consequence for blind people is that they were denied the educational opportunities that we normally give our sighted children. One blind person recently recounted her frustration at having to rely on verbal descriptions while taking a standardized test that is required for admission to many graduate schools in the United States. This person had already earned a doctorate, and was interested in education in another academic area. She was forced to rely on verbal Guest editorial Perception, 2000, volume 29, pages 757 ^ 760