Kennedy Plenary

John Kennedy, University of Toronto

In Vision and Touch, Dots Fit a Function:
A Theory for Museums Open to the Blind as well as the Sighted

In the last ice-age, people began making representational pictures, especially outline pictures. Alas, it has long been thought that these only suit the sighted, and the unfortunate result has been that blind people have been largely ignored by art galleries and art education. A revolution in recent decades has overturned this limit on our thinking about blind people. It is now obvious that raised-line tactile pictures work well for blind children and adults. They recognize raised-line drawings, and can draw with raised-line drawing kits. It follows that access for the blind to museums and galleries should be inspired by theories of pictures that apply to touch and the blind just as much as they do to vision and the sighted. To begin with, we need to explain how outline pictures work. Here is just such a theory. In vision and touch, lines fit a function. The functions can portray surfaces by depicting their edges. But further, surfaces and their edges are always perceived from vantage points. This is as true for touch as it is for vision, and for the blind as well as the sighted. (Kennedy & Juricevic 2006, Wnuczko & Kennedy 2014, Chao & Kennedy 2015). This fundamental thesis is essential for any accessible museum dealing in pictures. Pictures are as natural for the blind as they are for the sighted. Tactile pictures showing edges of surfaces from a vantage point can be be realistic. But tactile pictures can be a great deal more than that. Metaphors and expression can be highly effective in tactile pictures much as they are in vision. Hence, touch is open to a broad swathe of the arts in a fashion that is remarkably akin to visual art. However, there is much still needing an explanation. Coppin questioned how a set of dots can suggest a continuous line and depict a continuous feature such as a surface edge, though continuous features do not stand for dotted lines. Why is representation one-directional in Coppin’s sense? Here is an answer: To perceive a surface, or a swarm, or a flock, the elements making up the surface, swarm or flock must be grouped, and the statistics of the group must be extracted, as Cant argues. In the case of dots, the elements might pair-up, and then a set of pairs might fit a mathematical function. Of significance, the function would be continuous, even though the dots are separated. The function crosses the spaces between elements. This proposal solves problems of perception dating from the early twentieth-century Gestaltists. But in addition, the function permits perception of edges. The edges are perceived via linear perspective. Perception uses linear perspective well, with an important restriction. It underestimates azimuth changes as elevation increases, as both Juricevic and Wnuczko have argued. Juricevic studied perception of squares, and Wnuczko tested perception of angles. Their results are compatible. Further, Chao found very similar perspective effects in vision and touch, in the blind and the sighted, as the observer’s perspective on a scene is altered. The kind of representation in the Juricevic, Wnuczko and Chao studies is realistic. But blind people should not be limited to realistic pictures. Deliberate violations of realism should underpin metaphors in tactile pictures that should be understood and created by the blind. In principle, the blind should be able to create "trick" pictures, that is, to play with shapes that hide messages, much as sighted artists have done for centuries. In short, access studies needs a theory of realistic and metaphoric expressive shapes applying to the blind and the sighted. It should stimulate cross-modal demonstrations -- displays such as one by Alina Cioara in Art Encounters, Contemporary Art Biennale, Timisoara, Romania, 2018.

Chao, H.-Y., & Kennedy, J. M. (2015). Metaphoric Car Drawings By a 12-Year-Old Congenitally Blind Girl. Perception, 44(12), 1349–1355.

Kennedy, J.M. and Juricevic, I. (2006) Blind man draws using convergence in three dimensions. Psychonomic Bulletin and Review, 13 (3), 506-509.

Wnuczko, M. & Kennedy, J. M. (2014) Pointing to azimuths and elevations of targets: Blind and blindfolded-sighted. Perception, 43, 117-128.