The Human Side of Colour Blindness

(or Color Blind or Color-Deficient)

Copyright © 2000 Joseph G. O'Neil, All Rights Reserved.

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This article is for people who are NOT colour blind, in the hopes I can explain what it is like to go through life being colour blind, both on a physical and a psychological level. If you are colour blind, please read this article over, and feel free to share it with your friends and family if you think it will help.

A couple of years ago I posted a short article on my web page that dealt with the practical factors of colour blindness, and to my constant amazement I receive large number of visits to this rather obscure article. While there is plenty of factual information out there about colour blindness, it is of limited use for the following reasons:

1) Most articles are simply reiterating textbook knowledge about the subject, that is, saying the same thing over and over and over.....

2) Being colour blind myself, I get the feeling that many so called experts who address this subject know the theory, but are oblivious to the real world application of this knowledge. For example, a male doctor who writes an article on the pain of childbirth, no matter how intelligent he is or how well meaning his intentions are, simply cannot be as knowledgeable as a woman who has actually gone through the experience, or so my mother, my wife, and most of my female friends and relatives tell me.

Some time ago on an astronomy newsgroup I had a running discussion about the effectiveness of color filters for planetary use when you are colour blind. Now personally I find colour filters of limited usefulness for any visual use, day or night time, but I had several people tell me that I was seeing more detail. I finally grew so frustrated and blew up on line saying "look, you are not in my shoes or in my head, don't tell me what I am seeing!" The theory that the other writers posted was sound, but in real life application, it simply did not work, at least, not for me. here then, is how colour blindness affects my life, along with some personal observations.


I am not offend by the use of the term "blind", so neither should you be. I think in our current world we get to caught up in developing nice, non-offense, sometimes politically correct terminology to the actual detriment of working on the problem at hand. At first this idea of not using offensive words to describe people was an honourable idea, but like everything else in life, it has gotten out of hand. I think the best way to deal with a problem is to head it straight on, not think of yourself as a "victim" and do the talk show circuit. :)

I will use both the spelling "colour" and "color" because in this day and age of the Internet, I find people use both spellings for web searches, so I will make it easier to find. Also, I am a bit dyslexic, so please excuse any errors that escape past my spell checker. Finally, I have a bit of s twisted sense of humour, so take everything you read here with the knowledge that most of my more outrageous comments are written tongue in check. On the sci-fi movie "Alien" they say no one can hear you scream in space, but I find on the Internet, no one can hear you laugh, so listen closely, because I giggle most frequently. :)


Total color blindness, that is, where everything looks black and white, is very rare. But to understand "normal" human colour vision, you must know it is not a linear response, that is, normal vision does not mean you see all colours equally. Normal vision is more of a bell curve. Let me give you a crude example. In the electromagnetic spectrum, humans can see colour ranging form 400 nanometres (red) to 700nm (blue), kinda like this:

Infra-Red {} RED---------------GREEN---------------BLUE {} Ultra-Violet

Now, strictly for sake of argument, lets say "normal" vision is 100% and pure black & white is 0% colour effective. The average human being actually sees colour something like this:

----------------------------------------GREEN--------------------------------------------- 110%

------------------------------------------------------------------------------------------------- 100%

RED---------------------------------------------------------------------------------BLUE 90%

Now understand I am not a medical doctor, and this is a very crude example just to get the point across, but the average population is most sensitive to green. Sometimes I think maybe because all of our plants and grass and trees are green that over hundreds of thousands of years our eyes evolved to be most sensitive to the colours most readily apparent to our ancestors wandering outside in the plains, hunting game and gathering nuts and berries.

When someone is colour blind then, they might see two colours really good, one colour really good, they might be 90% red, 90% green, 20% blue, or they might be 25% red, 45% green and 85% blue, or any number of combinations.

The standard color blindness tests that have been around seemingly since the time of the pyramids are very crude, and definitions such as "red-greed deficient" are as about as accurate as the weather forecasts in the Farmer's Almanac. By that I mean, if you make something vague enough, it will cover almost all possibilities.

So realize that just as no two snowflakes are exactly alike, possibly no two people with color blindness are going to see exactly alike either.


Ten percent of the male population and around 0.5% of the female population in Canada and the USA are said to be colour blind. Now unlike other disabilities, people with colour blindness sometimes find themselves in demand for certain roles in life. For example, many hunting scouts and some specialized military roles are best suited by a person who is not fooled by colour camouflage. I have corresponded with many people who over the years due to their colour binders were the first ones to bag the deer in a hunting party.

Now regardless of if you believe in hunting or not, think of our ancestors, 100,000 years ago, hunting prey to try and keep their family or even clan alive. Out of a group of 20 hunters, one man has the fluke of being colour blind, yet his "disability" allows him to always be one of the first to spot and hunt down the prey. That means his family is going to eat first before all others, and his decedents are most likely to survive, thus preserving the genetic data that passes on colour blindness.

As for women carrying the gene but not suffering from it, perhaps the possibility that mostly males were the hunters and benefited most from the condition had something to do with how it has evolved over thousands if not millions of years.

The other interesting thing is not all, but many people with color blindness have excellent night vision. This is due to the fact that cones in the eye, which are bright light receptors "see" colour, while rods, which also happen to be the low light receptors, see gray tones.

As a child and to this day as an adult I have a terrible time in full bright sunlight. I almost never go outside on a sunny day without sunglasses as I find the bright light too unbearable. as a child, before I knew all this, I used to always walk with my head pointed down to the ground and I squinted all the time outside. Teachers and other concerned adults always assumed I suffered form low self esteem or some other techo-babble psychological condition, when all it was in the first place was the inability to walk in bright sunlight without experiencing pain in my eyes. To me, the full midday sun is like having a camera flash go on and stay on in my face. Not everyone is the same as me, but if you have child with aversion to bright light, it might be an indication of some form of colour blindness. Again, this is not such a bad thing, as when darkness falls, I move around very easily with minimal light. When out observing with my telescope or on dimly lit beach, I can move around a lot easier than most of my friends and/or family, so there are circumstances when color blindness can be an advantage.

This being said, I have often though about when the day come that through genetic manipulation we can eliminate many diseases and disabilities. I put this question to all of you - reading the past two paragraphs, if you had a child who was colour blind, would you use gene therapy to "cure" him or her, or would you see his difference as a valuable uniqueness? Don't answer that question too fast, but read on.


Imagine for the sake of argument that people could see Angels. You know, the white dudes with wings who bring down messages from God and guide us through our lives, of if you are an atheist, then imagine that every day of your life everyone could see UFOs daily in the sky, and aliens walking around among us in the grocery store, sidewalk, etc. Angels or Aliens, take your pick.

No imagine that due to a genetic condition, 10% of the male population could not see either Angels or aliens, no matter how hard you tried, no matter how many doctors you saw, no matter what you did, there was just no way you could see them

You spend your entire life where not just every day of your life, but every waking moment of your life people are saying 'oh look, that Angel is reading Time magazine" or "look that alien has thirteen eyes". But you never, ever see this. After a while, how would you feel?

Well, this is exactly what it is like to go through life colour blind. Every day, even people close t you - friends, wives, girlfriends, etc, ask you "wouldn't the colour in that wallpaper pick up the warm highlights in our carpet?" Or maybe"honey, how do you like my new eye shadow, doesn't it compliment my eye colour nicely?. Or better yet, you are a 10 year old at summer camp and the counsellor tells you "Okay John, today you play football on the red team" but you don't see the red team, or you cannot tell the difference between the reds and the greens.

It is FUSTRAITING like you would not believe. After a while, I find many people who are colour blind settle into one of two, crudely defined, fall into o's of these two categories, or maybe even a bit of both in some circumstances.

A) The Non-Believers

Since you spend your entire life questioning yourself and everything you do. Since you never can tell if your socks are matching, if you took the correct pill because they all look the same colour, or if that really was a red light you blew through even though the nice police officer is tellin you that it is so, you are still never just 100% sure. All your life people tell you about something that exists - colour - but something you cannot see - like our imaginary Angels and aliens. After a while you doubt everything to some degree.

B) The Believers

This colour blind person is more of a happy go lucky type of personality. after a wile, you figure, the heck with it, go with the flow. If people tell you that Angels and aliens walk among who, well what the hell, fairies, vampires, even the Loch Ness monster must exist too. Hey, you cannot see them either, but if all this other imaginary stuff exists, why not everything else too?

I am more of this second group myself, and I find that while I can prove the existence of red and green using film and colour filters and other methods of science, just like proving the existence of infra-red light or x-rays or radiation - all of which we cannot see but can be proven to exist, it is still something of a leap of faith to believe in that which you cannot see. You understand it in your head, but in your heart, there is doubt.

How this affects the colour blind person is you are more willing to accept the unseen world on some levels. This could be the unseen world of science or the unseen world of the paranormal. Sometimes though it can work the other way, and you can be both a "Believer" and "Non-Believer" all at the same time. Example for sake of argument - a person who empathically believes in the existence of the Loch Ness Monster, but is just as insistent in calling all UFO reports total bunk. Again I am exaggerating to an extreme, but I want to point out that being colour blind on how you see and think about the world you live in., and it is very difficult to explain this to somebody who is not color blind. In fact, for what it is worth, I have never really met any medical personal who have been even aware of this issue. It should also be pointed out that this kind of personality is not unique to people with colour blindness, but more ameasue of what goes through the mind of somebody who is colour blind.


My favourite coffee mug is a heavy stoneware model form Denby. For years I thought it was light blue in colour until one day my wife told me it was actually green From that point on, I now see it as green. Now if a year before that point you hauled me into a court of law, placed my hand on a stock of bibles 10 feet high, hooked me up to a polygraph lie detector, and threatened me with a day in chains and irons if I failed to tell the truth, I still would of told you that green mug was blue. Why? It goes like this.

While the eyes see images, it is your brain, like a giant computer, that processes information into the images that you actually "see". There was a famous experiment done many years ago where a group of test subjects wore special glass that had prisms in them that made everything look upside down. After a few days, everybody who wore these glasses started to see images right side up.

What happens is your brain "knows' that the world is not supposed to be upside down, so ti flips everything right side up. You see, when light hits your eyes, the actual image on your retina is really coming in upside down, so it si the brain that flips it right side up.

Now what happens in the brain of a colour blind person is very interesting. Let us say for sake of argument that a person can hardly see red. They can see yellow, maybe some orange and brown, but almost. When this person then looks at red stop sign or a red apple or the red skin of a sunburn, the brain is not receiving any "red information" from the eyes.

The brain can "see' red, it is the eyes that cannot, so this is an important distinction. Our test subject will moist likely "see' the apple as red or the stop sign as red, because he or she has been told since childhood that these things are red. However, lets say that our test subject is handed an object - a sheet of paper or a piece of fruit from a tropical location that he or she has never seen or heard of before in their life. The without any point of reference to go by, the brain will then assign a colour based on what information it has. This information can come form any source. For example, place that strange piece of fruit in a basket of oranges, and the test subject might assume it to be a deep orange colour, due to the association of the nearby oranges. However, lets say that same piece of fruit is one a white table cloth all by itself. The test subject may see that fruit as brown in colour, if something about that fruit reminds them of a coconut for example.

The reason I thought my mug was blue is because I bought 4 of them at the same time, and I thought I bought 4 blue ones, but I really bought 3 blue and one green. This is why somebody who is even severely colour blind will see red stop signs and orange Oranges and blue skies, it is because we have been both taught and trained to know what the colours are form the experience of others around us. However, drop us into a brand new situation with no frame of reference, and while you see a light red, I might see a light orange or a light brown.

I think this is what is most confusing to a person who is fully colour sighted and lives with somebody who is colour blind. Why do some days there appears to be no problem and the next moment major disaster? It is because of how the brain processes information that is given. What we see in our vision is not only dictated by the actual light coming into our eyes, but by the knowledge in our heads.

This is exactly why there are specific cases of people who have been sent to jail based on eyewitness accounts only to be exonerated years later based on DNA evidence which proves beyond a shadow of a doubt that they were innocent. Here in Canada the David Milgard case is the most famous example of this. DNA samples taken from the rape victim showed it was not him, but he languished in jail for years for something he did not do. Never underestimate the power of suggestion, especially when your eyes are not receiving all the proper information in the first place. For example, at night, especially under the cast of artificial lighting such as distant street lights, most normally sighted people have trouble distinguishing different shades of colours. Our colour vision is the result of hundreds of thousands of years of evolution under the light of our sun. Artificial lighting has a different colour temperature or cast to it, that's why even to a normal sighted person clothing can look different under indoor lights than form outside, and you can change tones from warm to cool all depending on what kind of artificial lighting you choose - flourescent, tungsten, mercury-vapour, lor or high pressure sodium, etc. Photographers, film producers, artists and other people involved in any industry involved with graphic arts are well aware of this situation, and use it to their advantage in everything from advertising to product presentation on store shelves to cosmetics and more.

Imagine then, if "normal" people can be led one way or another into seeing certain products or images in one fashion or another by the clever use of lighting and colour presentation, what then is it like for a person who is colour blind, not receiving all the information in the first place. It can go either way. You can be totally befuddled and confused, such as when buying 4 mugs and trying to get them all the same colour, or you can cut right though all the crap direct to the heart of the subject, like the colour blind scout in the hunting party who sees past the colour camouflage and nails the poor rabbit or dear before anyone else in the hunting party does. Sometimes being colour blind means living in a world of opposite extremes,


I've been married over 15 years now, and to this day, my wife will still occasionally asks me if I like the colour of her new dress, or if the new curtains in the Sears catalogue would look nice in our house, and so on.

Unless you are a really offensive person, most people would never think of asking a man in a wheelchair to climb a set of steps. Even somebody who is deaf will talk differently enough that you can sense that something is unique here, or a person who is totally blind will hold their head and their stance and their gaze differently form somebody who is sighted. The point is, we have both on a conscious and subconscious level the ability to pick up on another human being's disability and act accordingly, or try to behave in a civilized manner.

Ah but for the person who is color blind, the signals are not always there., and this can be heartbreaking in some ways. I did not know I was colour blind until my early 20's when I took flying lessons and had a colour vision test. How did I go through life so long without a proper diagnosis? My mother took me to the optometrist many times because I squinted all the time, and many "strange" things happened to me all my childhood that with the benefit of 20/20 hindsight can now be explained, but still, I had very caring parent, good access to medical care, and still nothing. How? I have a few points to lay out for you, then a personal story. The main point however is colour blindness is something a person can go through their entire life with, and never be noticed, even by caring people and even if it is a more severe form of the condition.


1) We live in an age with it is easier to give a child prescription to Ridalin than to take time and try to find out if something else might be the cause of the child's disruptive behaviour. even when I was growing up "psyco-babble" was just starting to flood the schools. As obvious as it sounds, people only look for what they are taught to look for, not to think outside those boundaries.

2) Most doctors don't know jack about color blindness. Since it is not a curable or treatable condition, why waste money and resources on it? I know about it because I live it and can look back upon my life about it, but to most medical personnel and social workers, they only know what they read out of textbook, and if it was a warm Friday afternoon when that class was held, they probably skipped it.

When I was very young in school, especially around grades 2 and 3, I was a lot of trouble, a class clown. I remember one day, it WAS a Friday afternoon, in the late spring, warm summer like day, not too far from the end of the school year. During the late afternoon after recess all the children one by one left class and returned a few minutes later. I did not know what was going on, so when my turn came up, I was sent to a small office where a nice young lady had a book of about 15 pages with circles made up of coloured dots. I later learned this was your standard colour vision test, but I did not know that then.

The very bored and tired looking lady asked me to read out the number or letter on each page. Well, I simply could not do it, I told her there was no letter or number. The lady looked at the clock on the wall, grew very angry with me and nd told me that she knew I was a trouble maker in class, and look again. I was very scared by this time, and the last thing I wanted to do was get in trouble again, as it was almost a weekly ritual with me at this point in my life.

So I tried very hard, but I could not see any numbers or letters, except on maybe 2 or 3 of the 15 pages. The lady grew very frustrated and angry with me, berated me even more and said "Look again here, there's the letter B, can't you see it?" While by this time I was fighting back tears on the inside, so I said yes, anything to get the hell out of that room and avoid trouble. The same coaching happened on a couple more pages and then I was dismissed back to my classroom. Shortly later school ended and I ran home, too terrified to tell my parent about this event.

The reason I remember it all so well si because it was the first time I got into trouble at school that the teacher or principal did not phone home to my parents. I was in fear all weekend that my failure on this test would be reported to my parents and anger them very much, but nothing more was ever said of it, so I counted myself lucky and never said a word to anyone until the day I was in the doctor's office for my flight medical, and upon failing a very similar test, was told "you're color blind."

I'll end my story here in the hopes that somebody will benefit from it. I may add more or update ti as time goes by, but I have I have given you a brief glance as to how colour blindness looks from the other side. My only regret is that I did not know sooner, for while I could not of been "cured", it would of made my life much easier. No more teasing due to my bad choice in cloths as a teenager, no more being yelled at by my dad from grabbing the wrong coloured handle screwdriver, and more. Imagine being locked in a wheelchair but not realizing you are in one, and then trying to go swimming or climb stairs while still in that chair. Again I exaggerate for the sake of illustration, but that is what my life was like, looking back on things. All my life I lived with various labels instead of an accurate diagnosis of my real state in life. I wonder how many other people this happens too, but children and adults? I hope this article will help at least one other person avoid the same fate I had.

Oh yes - for the record, if medicine ever develops a "cure" for colour blindness, I'll not have any part of it. I've come to learn that who and what I am have been shaped by my "disability", and I would not change that for all money in the world.