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The question of what totally blind people see may appear straightforward, but the answer is far more nuanced. According to the National Library of Medicine, visual impairment can be categorized into low vision, visual impairment, and blindness. About 15% of individuals with eye disorders fall into the blindness category, and even within that group, experiences vary widely.
Most people with visual impairment retain some level of sight, and those who are classified as blind often can detect light. The exact proportion of individuals who are completely blind with no light perception is unknown, but it is estimated to be under 10% of all totally blind people.
Because of this, the common intuition that a totally blind person lives in a world of pure black—much like the darkness we feel when we close our eyes—is a misconception. The reality is more intricate and, in many ways, fascinating. In short, totally blind individuals do not perceive the color black; their visual experience depends on several factors.
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Vision relies on light striking the retina, the light‑sensitive tissue at the back of the eye. The retina converts this light into electrical signals that travel via the optic nerve to the brain. Within the brain, the visual cortex processes these signals to produce conscious vision.
When vision is impaired, the ability to experience conscious vision is altered, but it rarely disappears entirely. According to the American Foundation for the Blind, only a small fraction of people with visual impairment experience total blindness. About 85% of those with visual impairment retain some form of sight—whether it is basic light perception, blurred vision, loss of color, or peripheral vision loss. Total blindness, defined as a complete lack of light and form perception, affects roughly 15% of those with visual impairments.
Even within this group, individuals may still report visual sensations, which depend on when and how they became blind.
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For someone who becomes totally blind without light perception, does that mean a life of darkness? Journalist Damon Rose, who lost his sight as a child after surgery, was registered as completely blind with no light perception. Yet he describes a visual experience of “bright, colourful, ever‑changing, often terribly distracting light.” According to Rose, this phenomenon is not actual light in the environment but rather the brain’s compensatory response to the absence of visual input.
What about those born with total blindness? They do not perceive the color black, simply because color is meaningless to someone who has never seen it. Their experience is a fundamental absence of visual sense. Nonetheless, research shows that blind individuals can conceptualize color similarly to sighted people.
A 2021 study in Psychological & Cognitive Sciences compared blind and sighted adults on questions about common objects—fruits, plants, pens, dollar bills, and more. Participants were asked about the typical color of these items, the reasons behind those colors, and whether two randomly chosen objects would share the same hue. While blind participants sometimes differed on the specific colors (e.g., calling bananas yellow), their reasoning about why objects are certain colors and whether two items are likely the same shade matched that of sighted participants. This suggests that even without visual experience, people develop intuitive “theories” of color based on non‑visual information.
In short, blindness does not erase the mind’s capacity to process and understand visual concepts; it simply changes the way these concepts are formed.
