Looking around your town or city, how many people would you estimate are disabled ?

We asked this question to ourselves and our students, and were startled by the responses. The estimates were unanimously and significantly low, most of them less than half the actual number.

According to the WHO , a full 15% of people in the world lived with a disability in 2011. Census records show that in the U.S. that rate is about 19% as of 2010. Disabled individuals constitute the largest minority in the world and yet, for the most part, the general public barely notices them.

This is not because the rest of us are turning a blind eye to the disabled. Rather, in an ironic twist, our experience is narrowing our perception and preventing us from acknowledging the existence of our disabled peers.

Out of sight, out of mind

Research by us and other behavioral scientists suggests that we are hardwired to learn from experience, seamlessly and automatically. Our senses collect the information offered by the environment around us and feed our intuition. In his book Thinking Fast and Slow , Nobel laureate Daniel Kahneman dubs this syndrome what you see is all there is. Unfortunately, however, it rarely is.

For the most part, disability is not all that prevalent in our experience. When we go out, go to work, to the gym, to the grocery store, the theater , a caf or a restaurant, what percentage of people we see and meet are disabled?

Painfully few.

Thats because many disabled people simply cannot go out, work or live like those of us who dont have a disability. They become invisible. Nonexistent. Which, in turn causes further marginalization and exclusion. This ominous cycle eventually ends up filtering out a large portion of the population from everybody elses daily experience.

Thus, disability rights activist Lisa Egan argues that disabled people, rather than people with disability, is the right term to use in this context, since it is mainly society -- not their specific medical conditions -- that ends up disabling them.

Experiencing disability

While we can easily empathize with experiences we relate to, we often fail to acknowledge accurately what we dont experience. This is another way in which experience narrows perceptions. The hardships of disability will inevitably be discounted in the mind of a person without a disability. To be able to truly empathize, we need to acquire personal experience.

The teenage daughter of a friend of ours recently attended a summer school in Denmark where each participant was assigned a disability during part of the day. One had his eyes covered for a few hours, while another had one of her arms tied to her body. They were asked to engage in daily tasks, such as doing homework, eating, or going to the toilet. After some time, they rotated to experience another disability. While they could all imagine having a disability, actually living with one had a profound effect on them. They could truly understand the design flaws and obstacles that the disabled have to face every day.

Everyone can develop a similarly empathetic perspective. Its a matter of walking a mile in the shoes of a disabled person, or going the same distance in their wheelchair. And technology can help simulate different disabilities. For instance, we recently stumbled upon some special glasses that render you colorblind . Anybody wearing these will immediately start to notice various design flaws in everyday gadgets and tools. For example: the green and red on-off lights on most electronic devices can make it difficult for a colorblind person to distinguish on from off.

A day for the disabled, spent with the disabled

The United Nations has designated December 3rd as the International Day of Persons with Disabilities . How can we use this day to render the disabled more visible and help people empathize with them?

One way for people without a disability to achieve this is to simply make a habit of spending that day with a disabled person outside the house. For example, go for a walk in the park, to a movie or a museum. Accompany him or her on any errands that are possible.

If youre not sure how to get involved, there are a few organizations that can help. Try contacting The Arc , Friendship Circle International , or The Federation for Children with Special Needs . The Arc has an extensive list of local chapters to put you in touch with someone nearby.

This simple act would have several immediate benefits:

Increased visibility. It would generate awareness and help prevent marginalization, given that many disabled individuals would be out in public and visible.

Personal experience. It would provide people with the opportunity to interact with a disabled person and have a glimpse of many everyday problems that the largest minority in the world has to live with.

Support and solidarity. It would help people credibly signal to others around them their concern for issues related to disability, encouraging them to act as well.

Fifteen percent of the world population is far from trivial. And disabilities are not simple quirks in a system that can be ignored or repaired over time. The disabled are a growing part of the world community, primarily due to aging. They have the right to attain and enjoy adequate living conditions and, most importantly, to exist. To achieve this, however, they could use the empathy of the other 85%.