We are editing this chapter for a book. It begins as a readable piece and drops to the level of notes and sentence fragments.

The pages that follow are about complicated navigational technologies for the blind, but the full story is inseparably about a few stubborn inventors standing at the edge of society's boundaries.

I first met Dr. Steven Mann in Toronto's China Town, in a small restaurant on College Street. Steve was the director of the Personal Imaging Lab at The University of Toronto. All accounts said that he was an eccentric genius; the media called him the Father of Wearable Computing.

Steve had on one of his homemade cyborg units; it was mounted on what looked like an old eyeglass frame. As he talked, Steve would say "Doug Baldwin would like to order Wonton soup;" stuff like that, using my full name. I glanced over at Mike May who had accompanied me on this visit, but Mike was totally blind back then and there was no emotion to read on his face. "Mike May would like orange chicken."

When he was a graduate student at M.I.T., Steve's colleagues made him wear a red light on his cyborg inventions because Steve had a habit of transmitting everything he looked at straight through to the internet; the red light came on when he was hooked to the web. People logged in from all over the planet to look through Steve's left eye. Some gorgeous chick from Sweden was probably looking through Steve's left eye back then, wondering why I didn't take better care of my hair.

Steve turned out to be a gentle and slightly crazy guy whom I've come to respect and enjoy. I'm reminded of Zorba the Greek's words "A man needs a little madness, else he never dares cut the rope and be free."

Steve has a visual memory problem. His cyborg system is a memory prosthesis; a life long photographic storage unit. "Doug Baldwin laughs nervously as he glances at the Eyetap." Eyetap, the core invention that powers the cyborg unit, places a computer modified laser image directly onto the retina. Steve has invented digital vision, a new way to perceive. Along the way, he also self-diagnosed his vision problem, engineering a solution that far transcends his initial intentions. I refer to the various Eyetap incarnations as "Mann Glasses".

Mann Glasses are a revolution. They are individually prescribed, providing potential digital solutions for a full rainbow of problems or desires. To understand the potential of Mann Glasses, we need to examine the full scope of human blindness, both in normal populations, and within disability categories.

My experience in the blindness field spans over 30 years, most of it teaching blind children. As these years rolled on, I became increasingly aware that human beings are mostly blind. Public understanding of blindness is simplistic: there are people who cannot use their eyes to gather visual information; and there is the rest of us fortunate souls. Ten minutes in the presence of Mike May or Dan Kish, two of my blind friends and colleagues, quickly dissolves the visual ego. Characters like Steve Mann, who see in various perceptual modes, challenge the very notion of what it means to "see".

Vision is just a perceptual oval that floats on the front of the face. Human beings are blind everywhere else; there is no vision behind, above, or below. If you want to experience blindness, just look out the back of your head. Using Mann Glasses, a person could see 360 degrees, depending on where attention was focused. If you wanted to look out the back of your head, you could.

It is a common and forgivable misconception that there is just one vision system. Unfortunately, vision is mind boggling; it is incredibly complex. To begin with, there are two separate vision systems. Each vision system has a network of neural tracts. Each has independent cortical control centers. Each can be selectively blinded. Functionally, these are called the peripheral vision system (used for navigation, primarily), and the central vision system (used for communication, primarily). Peripheral vision is also called the "Where system" (Where is it? where am I? where are you?). Central vision is called the "What system" (What is it? Who is it? What is this landmark?).

The central system is conscious. It is aware of the "self". The peripheral system is not conscious. It is blind to the "self". Have you ever daydreamed in a car going 75 miles an hour on a busy expressway? Where were YOU during the daydream? Who was driving the car while you were out? "You" were gone and the driving was being accomplished by the unconscious peripheral system. It can drive blind.

We don't recommend that you daydream and drive blind; this is a good way to die young or take out a family on vacation. Digital Mann Glasses could communicate with your car when you daydream, in "driving assistance" mode.

What we call visual memories and visual attention are really elements of central, conscious vision. We cannot consciously access peripheral visual memories. When we move our eyes around to "pay attention" to something, we are directing central vision to gather information about things we have to study, talk about, remember. Peripheral vision is reflex vision; it sits there waiting for sensory input. You cannot "will" peripheral vision. All human beings navigate using a "blind" vision system. Could Mann Glasses be used as prosthetics to counter the numerous ways human perception limits our abilities?

Although both vision systems process information in parallel and they appear to cross talk at all important brain way stations, they do not pay attention simultaneously. When we are deep in concentration, studying, focusing at near point, the peripheral system is suppressed; it goes blind. When an object suddenly appears in the corners of view, the reflex action of peripheral vision takes over, suppressing central vision; which, in effect is blind all the while the peripheral system is doing it's job. This is (my definition) alternating, attentional blindness. If the suppression of the peripheral system's attention system is sufficiently strong, we could get hit in the head or by a taxi. If our attention is constantly pulled to the periphery, we might fail the final exam.

Remember that vision is an oval in front of the face. When we concentrate, using the central system, we suppress peripheral vision, effectively shrinking that oval of perception, and increasing the zone of blindness around our heads. We also close our eyes at a "blink rate". While the eyes are closed of course, we are blind. Blink rate is so fast that we do not notice the intervals of blindness, nevertheless this adds to our "vacant" (not at home) moments.

The attentional system of central vision is serial. It can only process one thing at a time. It can do it very quickly, so fast we aren't usually aware, but our eyes can only be pointed in one location of space at a time. Meanwhile, we are relatively blind to all the other locations in space. Our peripheral system is operating unconsciously in the immediate field, but it may be suppressed to various degrees depending on how hard we are concentrating at the point in space.

There is a famous experiment that demonstrated what the researchers called inattentional blindness.

Human beings are also situationally blind. Driving into the sunset, driving beside a tall truck or bus while looking for road signs, trying to find a small child in mob scene, all these are moments of situational blindness. Our vision is blocked, made ineffective; it is not able to do it's job.

In the complete absence of light, of course, we are totally blind creatures. As light intensity drops, central vision is the first of the two systems to begin to lose function; it slowly gets more visually impaired, until it no longer can see at all in dim light. We become increasingly color blind, and we lose our sharp 20/20 acuity. Only the peripheral system can see black and white blurry shapes and shadows in dim light. We also slowly lose our ability to see details; our acuity drops to 20/200- legal blindness, the maximum acuity of the peripheral vision system.

Notes:

Blindness: visual complexity and degrees of categorical lose (as in diabetes); relative blindness- eagle acuity, infrared and ultraviolet ends of the spectrum; lead in to digital vision and alternative vision mediated and augmented; effect of change- developmentally; aging; medications dose fluctuations; diet; diseases;… why none of us sees the same; nothing too far and nothing too near; blind visual fields; reading human emotion in the face and in the body and in the movement patterns in a social setting

Intr: Steve to Dan (create a world the blind can see- audification, choices, turning the environment on and off lead into Mike) to Mike; alternative perception as a solution to human blindness broadly defined; 3 major avenues and convergence; environmental literacy and Mike and talking signs; smart spaces and network of networks