Sighted people cannot function well in low lighting conditions and are generally completely helpless in total darkness. Their homes are usually very brightly lit at great expense, as are businesses that cater to the sighted consumer.

19th century devices and objects, made for the blind, served to extend senses in the sighted architectural world in relationship to the body. A cane therefore was an extension of the arm. Recent technological devices substitute this direct material and body relationship with a mediated experience, For example, a computerized voice (disembodied sound) in a tape measure, unlike previous versions in which the measurements were read by Braille -- a sense of touch. The computerized voice transforms the private space experience to a
public space, and fills the silence.