Do we all see the same colours ? Is the “red” you see the same as the “red” I see, or have we just been taught that the colour we see is “red” ?
Is it just some social conditioning ?
Surely I could teach my kid that red is in fact black ?
You could teach him that the colour he saw was called black, but it would not change his perception of it. Just as you could teach him that steak was in fact peas, or sugar was called salt.
You would also have to decide what to call black.
The question of colour perception probably has two answers.
One, we know that not everyone perceives colours the same way, because their eyes have different mixtures of sensitive elements. In simple terms, some people are colourblind. This isn’t a cultural or learnt thing. And it is reasonably easy to measure. Also, there are varying degrees, not usually called colourblindness, and they may be simple perceptual deficits, where you have difficulty perceiving nuances in some part of the spectrum.
Two. We tend to assume that that perception works the same in humans, insofar as we all come from much the same blueprint. Our ability to converse sensibly about nuances of colour, and the fact that we agree on the results of things like the colour of a mixing of pure wavelengths supports this notion. We also tend to ascribe much the same qualitative senses to colours, with warm, cold, vibrant, sickly, and the like being pretty much agreed upon. The success of colour designers in creating well recieved colours, and colour combinations also supports this.
Basically, there is a pretty complex colour theory, and it seems to work pretty well. It is sufficiently complex that it is very hard to imagine that people have indivdual colour perceptions, and yet the theory still works. It also works for people who are colourblind, insofar as we can predict what they can’t perceive, and what limited part of the colour space they can.
But the final pure sensation? Short of some sort of pure brain interlink, we don’t know.
The visible spectrum is just that, a spectrum, and the points at which we transition from one colour name to another are to some extent arbitrary, and one culture’s colour-names do not necessarily coincide with another’s. And different cultures describe the rainbow as having 3, 4, 5, 6 or 7 colours.
The Irish words glas and uaine, for example, are both translated into English as green. But, to an Irish speaker, an object which is glas cannot be described as uaine, or vice versa. Nor is there any word which embraces both. So and Irish speaker does not consider glas and uaine to be two different shades of green; he considers them to be two different colours.
But that’s not what the OP’s talking about. The OP is asking whether we know for certain that 2 people will each perceive the same shade of uaine in the same way.
But what do you mean by “red” or by “black”. Your kid would end up using the word “black” to describe the phenomenon you and most others think of as “red” - it wouldn’t change anything else. You still don’t know what your kid (or anyone else) actually sees in her mind when she observes that phenomenon.
(On edit; on re-reading FV’s first sentence I see that it says pretty much the same thing).
I’ve often wondered this myself, but I can’t see how you can ever know. As someone once said, in response to the question of what it would be like if someone saw, say, green as I see red, “what God could tell the difference?” As far as I can see, we can tell through tests whether people can distinguish different colors and identify them consistently, but unless we find some unique way of tagging which color looks like which, say by identifying the region of the brain that recognizes green, and seeing it activate, I don’t know how we could get close to the answer. And even then it’s not clear to me that we’d all be perceiving “green” as the same color.
I first started wondering when I was 6. I asked my younger brother what colour his glass of milk was. He naturally said “white”. I think I was vaguely aware of flaws in my methodology but I was unable to think of ways to take my experimentation any further.
Other past threads on this. Please see a synopsis and links at the Unofficial GQ FAQ.
Among the most interesting posts was one poster who said that he sees slightly different shades in each of his eyes.
Considering neurons are pretty uniform, I would assume that red looks like red to everyone. Ignoring language, vision issues, etc, in normal and healthy people we are probably perceiving the same firing of neurons.
Considering we attach emotional values to colors (warm colors, cold colors, bright colors, sad colors, etc) it seems unlikely that we could have this consensus which artists have been utilizing since the dawn of man, and perceiving different colors in our heads.
You see colours. I see colors.
Clearly our brain structures are substantially similar between individuals to be able to perform similar functions consistently at a macro level, but (just my opinion) the chances of any two individual’s brains firing the exact same set of neurons in the exact same pattern in response to the same input is probably extremely low (real close to zero).
Perhaps on the micro-level but on the macro level, brains operate very similarly. We have seen parts “light up” when exposed to similar stimuli. Why would one person see green when their eyes are sending a ‘red’ signal? We dont have people who feel pleasure instead of pain. Not all things are learned responses.
Another scenario that makes this unlikely is that evolution would select against this. Predators, poisonous animals, etc tend to have bright coloring. If we all perceived random colors it would be difficult for us to learn which are which or which to have the proper emotional response to. Lots of animals have strong responses to the colors of predators. This wouldnt seem possible if colors were arbitrarily perceived.
I had a friend with blue-yellow color blindness. That is to say, he saw blues and yellows as various shades of gray. He knew that “bright” blue and “bright” yellow weren’t actually gray, but he couldn’t describe what exactly the difference was.
And since colors are a spectrum, what I call “blue” you might call cerulean, navy, robin’s egg, etc., while what you call “blue” I might describe as aqua, turquoise or whatever.
He’s your younger brother. You could have tried hitting him a few times to see if that affected the results.
But, we don’t know whether this emotional value is innate and absolute, or purely conditioned due to real life experience.
I believe it’s probably impossible to say with any degree of certainty if any two people perceive colors differently…unless it can be proved that certain absolute color perceptions, free of experience bias, trigger an absolute emotional response—and even then, it would take a hypothetical experiment to find out.
Let’s assume that a shift in color perception does exist between people. We do have emotional responses to colors, but how do we know if this response is innate, due to an absolute color perception, or whether it is conditioned, due to real world experience? I don’t think we can tell. For example, perhaps the positive emotional response to what I perceive as green is based on my positive experiences with what I perceive as pleasant green things (e.g. grass, trees, etc.). How can that be differentiated from someone else who has the same positive emotional response to what they perceive as green being based on their positive experiences with things that they perceive as green? They could be the same color perception across the board, or they may be different—no way to tell. People growing up in a colored world may acquire emotional responses to relative color perceptions, or we may have deeper seated innate emotional responses to absolute color perceptions…but how can we tell the difference and how can we test for it? I think we would have to take a population of people from birth and have them grow up in a colorless environment (like the Mary’s Room experiment). Then, at a certain age, we’d have to run a color experiment on these people, flip card style, to determine if, and what type (s) of emotional responses they each have to different wavelengths of colors. If no pattern emerges, I suppose the experiment fails: no absolute emotional response may exist to any absolute color perception. We can only conclude that the emotional responses are based on experience, and that we still can’t tell if a color perception shift exists or not. However, if a response pattern does exist in this group of people who are seeing colors for the very first time (and therefore have no vested emotional response based on experience), then I believe we can draw conclusions based on the findings: if a significant % has a similar positive response to the exact same wavelength of color, I think we can conclude that absolute emotional responses to certain colors does exist, and, in this case, everyone perceives the colors the same way (I believe this result has a high degree of accuracy). If a pattern of emotional responses to color emerges, but to dissimilar wavelengths of color, I think we can conclude that an absolute emotional responses to certain colors does exist, but, in this case, at least some people perceive colors differently (I believe this result has a lower, but still significant, degree of accuracy).
"Do we all see the same colours ? "
PROBABLY NOT!
We now know that new world monkeys do not all see the same colors.
They have different alleles in their species, so it’s entirely possible that the same thing happens in humans.
“New World male monkeys are chromatically challenged because their ancestors split off from Old World primates before full color vision evolved. At the time of the split, primates had only two visual pigments, one that is particularly sensitive to blue light and another that responds best to either green or red, depending on which variant of the gene is inherited.”
With Genetic Gift, 2 Monkeys Are Viewing a More Colorful World
The colors you respond to depend on the pigments reacting to light in your eye. But we know that pigments are variable, as seen in the range of iris colors. Unless you check every single person’s retina for every dye, you will never know if a new allele has created a new pigment and changed that person’s vision. The sheer odds favor more that three total pigments, in fact I recall but can’t find a link, that more pigments have already been found in people we call colorblind. The “normal” pigments overlap a good deal in response to the spectrum, so pigments that are more separated would presumably produce a wider range of responses.
A quick scan through the replies above, I didn’t see any mention of surrounding colors.
Somewhere on Wikipedia someone had a long list of references to optical illusions, several were to color illusions. We, ourselves, with our own eyes, don’t even see the same colors when looking at the same thing, sometimes.
Depends on the opsins in your eyes. Different people will see slightly different colours but the difference will be negligible. Different species, however, see vastly different spectra. The goldfish, for example, has the widest range of vision, seeing from the far infrared all the way to ultraviolet.
I wasn’t thinking as extreme as red vs green (although, clearly some people will be wired weird and get confused signals, e.g. synesthesia), but by the time the color is perceived it’s gone through so many layers of filtering/mapping etc. that the perception by each individual is most likely unique even if substantially similar also.