Does colour exist if you can't see it?

[anonymous-user]

Something I heard on the radio this morning while in the shower.
Another one of those stories that makes me wonder if anyone goes to school/university anymore.

Science guy was on Radio 4 talking about evolution of eye and importance of sight in elevating humans to top of food chain etc etc.

Then states: Colour only exists in the mind. Without the eye, the world doesn't have colour.

All stated, as fact, with the import of great scientific fact having been imparted to the world.

As though to say, guess what, you won't believe this, it'll blow your mind, colour doesn't exist if you can't see it.

My shower drowned out the radio at that point so I didn't hear if the journalist pulled him up on it but I doubt it as the focus was on his eye nonsense.

Now where's my cat? I can't see it so perhaps it just doesn't exist anymore.
Strangely, that often happens. Perhaps it'll exist again in the future? Who knows.

[Alex]

Light is a wave and colour is determined by the wavelength and frequency. So it exists even if we can't see it, but to identify colour, you need a detector, of which the eye is one.

[Eric Mc]

Of course it does. I think what the scientist was trying to say was that before the evolution of eyes, there was not much reason for many life forms to make use of colour as it could not be seen by other life forms and offered very limited evolutionary advantage.

That does not mean there was no colour on earth. Plants would still have been green, for instance, because that is a natural fall out from the adaptation of using photosynthesis.

[anonymous-user]

Alex said:

Light is a wave and colour is determined by the wavelength. So it exists even if we can't see it, but to identify colour, you need a detector, of which the eye is one.

Of course.

Many things are difficult to perceive but an inability to perceive them does not mean they don't exist.

I've been trying to replay the guy on BBC iPlayer but Flash is playing up.

And this guy is an 'expert'!

[Eric Mc]

irememberyou said:

Of course.

Many things are difficult to perceive but an inability to perceive them does not mean they don't exist.

I've been trying to replay the guy on BBC iPlayer but Flash is playing up.

And this guy is an 'expert'!

I think you are misinterpreting what he was implying. I didn't assume he was saying that there was no colour. What he seemed to be saying was what I have said above, that animals in particular didn't need to make use of colour (for camouflage, attracting mates, warning of danger etc) when they did not possess the ability to see colour - so those adaptations had to wait until eyes evolved.

[anonymous-user]

Eric Mc said:

Of course it does. I think what the scientist was trying to say was that before the evolution of eyes, there was not much reason for many life forms to make use of colour as it could not be seen by other life forms and offered very limited evolutionary advantage.

That does not mean there was no colour on earth. Plants would still have been green, for instance, because that is a natural fall out from the adaptation of using photosynthesis.

Exactly. Seems obvious, doesn't it.

Did you hear the report yourself?

I'm just amazed that he could say it and, even in the 'excitement of the moment' of being on the radio (yay!!!) not realise what he'd said and correct himself.

Or, does he believe he's correct?

And, if so, why/how?

[anonymous-user]

Eric Mc said:

irememberyou said:

Of course.

Many things are difficult to perceive but an inability to perceive them does not mean they don't exist.

I've been trying to replay the guy on BBC iPlayer but Flash is playing up.

And this guy is an 'expert'!

I think you are misinterpreting what he was implying. I didn't assume he was saying that there was no colour. What he seemed to be saying was what I have said above, that animals in particular didn't need to make use of colour (for camouflage, attracting mates, warning of danger etc) when they did not possess the ability to see colour - so those adaptations had to wait until eyes evolved.

Well, fair enough, but we don't actually know what he meant because his language was vague/inaccurate.

You're placing your interpretation on his words to create a meaning which makes sense to you. But he may not be implying that at all. He may genuinely be asserting as 'fact' that colour doesn't exist.

I happen to agree with what you're saying but I'm perhaps less generous to the scientist whose language was, to my mind, careless.

And if it wasn't careless language, and he believes with scientific justification that, as he said, colour did not actually exist and is 'in the mind' - then I'd have enjoyed a proper explanation.

Careless talk just rubs me up the wrong way because he's on there raising awareness, effectively 'teaching' and when one teacher or expert gets it wrong, they make it twice as hard for the next one to convince people.
Just a pet bugbear of mine

[Eric Mc]

irememberyou said:

Exactly. Seems obvious, doesn't it.

Did you hear the report yourself?

I'm just amazed that he could say it and, even in the 'excitement of the moment' of being on the radio (yay!!!) not realise what he'd said and correct himself.

Or, does he believe he's correct?

And, if so, why/how?

Indeed I did - and I thought he was being sloppy rather than being stupid.

[anonymous-user]

Eric Mc said:

irememberyou said:

Exactly. Seems obvious, doesn't it.

Did you hear the report yourself?

I'm just amazed that he could say it and, even in the 'excitement of the moment' of being on the radio (yay!!!) not realise what he'd said and correct himself.

Or, does he believe he's correct?

And, if so, why/how?

Indeed I did - and I thought he was being sloppy rather than being stupid.

Well, I never said or implied he was stupid.

But sloppy to the extent that he raised a query on the breadth of his knowledge.

If he'd stuck to the eye stuff he'd have been fine but he fell down on the philosophy.

Edited by irememberyou on Friday 8th December 11:32

[Eric Mc]

He seemed to be trying to link the evolution of the ability to see in nature with transparency in business brought about by new media.

That sounded a bit far fetched to me and also sounded to me that he was using the opportunity of speaking on radio to do a bit of plugging of his department for funds from business.

He obviously didn't want an opportunity slip by

[Dr Jekyll]

I think what he meant was that although different substances absorb or reflect different wavelengths of light, those wavelengths are only represented by colours in our brains. Like those weather charts that have hot places in red, warm in orange and so on according to an arbitrary code.

[Eric Mc]

The colours are genuinely there.

How we personally perceive each colour will be a bit unique to each of us based on our own individual eyes and how our brain interprets the signals from our eyes.

Other creatures will also see colours in a different way based on the structures of their eyes (which can be very different to what we have) and their brains..

[Simpo Two]

Eric Mc said:

He seemed to be trying to link the evolution of the ability to see in nature with transparency in business brought about by new media.

Yes, it made good sense up to that bit of patent bks.

Still, it made a change from the usual interminable whining about Brexit.

[Toltec]

Dr Jekyll said:

I think what he meant was that although different substances absorb or reflect different wavelengths of light, those wavelengths are only represented by colours in our brains. Like those weather charts that have hot places in red, warm in orange and so on according to an arbitrary code.

The irony being that doing so is really in reverse as for objects glowing due to temperature red is much cooler than blue.

Eric Mc said:

The colours are genuinely there.

How we personally perceive each colour will be a bit unique to each of us based on our own individual eyes and how our brain interprets the signals from our eyes.

Other creatures will also see colours in a different way based on the structures of their eyes (which can be very different to what we have) and their brains..

In the sense that narrow spectrums could be said to be ultraviolet, blue, green or red etc. then yes colour exists without anyone to perceive it. What about colours made up of wider or multiple spectral ranges, for example what frequency is brown?

If you took a group of people and taught them what blue was and what green was, then showed them a set of colours in the range between and asked them to say if the colour was blue or green the point at which they change from one to the other would be across a spread of samples.

If you show a group of people a painted surface, ask and record their answers for the colour, then continue asking as you gradually changed the spectral output of the source illuminating it how many would continue to say it is the same colour even though the actual spectral distribution reaching their eyes is not the same? See the dress thing from a few years ago. If you had a separate group showed them the same sample at one spectral illumination then implied you wanted to know the colour of the next sample but just changed the illumination how many would see the same colour?

What I am trying to point out is that you could show a group of, non-colourblind, people a set of colour samples that they should all give the same answers to, then another carefully chosen set of samples that you would get a range of answers to. While colour exists it is not something that can be easily or absolutely defined using human perception.

[CanAm]

If a man makes a statement in a room and there is no woman there to hear it, is he still wrong?

[RizzoTheRat]

Eric Mc said:

The colours are genuinely there.

How we personally perceive each colour will be a bit unique to each of us based on our own individual eyes and how our brain interprets the signals from our eyes.

Other creatures will also see colours in a different way based on the structures of their eyes (which can be very different to what we have) and their brains..

Surely what's there is just light at a wavelength of around 500nm, we interpret that as a colour but does it really mean it's a colour any more than a string of 1s and 0s zipping along a wire is picture/website/conversation?

Although by that definition quite a lot of colours don't exist at all, pink for example is our interpretation of seeing several different wavelengths, and yellow is a defined wavelength but we only see in red, green and blue so get a mix of those.

[amancalledrob]

Colour only exists in the mind of the beholder, so Radio Professor is right. This was first realised by Newton and is not a new concept. Objects don't have colour, they just have properties that cause them to absorb or reflect certain wavelengths which you perceive as a colour.

Take a TV screen for example producing the colour yellow. It does this by using red and green wavelengths, but those wavelengths don't 'mix' - your eyes detect them both and your brain manufactures "yellow" from that. The colour of an object in almost all cases (flourescence is a bit special) depends entirely on the wavelength of the light bouncing off of it.

[Eric Mc]

You are getting a bit existential.

The phenomenon of light and its different wavelengths exists - our eyes and brains interpret this phenomenon as a colour.

Different species will interpret the phenomenon in a different way depending on the types of eyes they posses and how their brains work. Therefore they will see colours differently to us.

And individuals within a species will also have some differences in interpretation due to individual differences.

But to claim that light and colour only exists because we can see and sense it ourselves is nonsense - and a bit self centered to be honest.

[anonymous-user]

RizzoTheRat said:

Eric Mc said:

The colours are genuinely there.

How we personally perceive each colour will be a bit unique to each of us based on our own individual eyes and how our brain interprets the signals from our eyes.

Other creatures will also see colours in a different way based on the structures of their eyes (which can be very different to what we have) and their brains..

Surely what's there is just light at a wavelength of around 500nm, we interpret that as a colour but does it really mean it's a colour any more than a string of 1s and 0s zipping along a wire is picture/website/conversation?

Although by that definition quite a lot of colours don't exist at all, pink for example is our interpretation of seeing several different wavelengths, and yellow is a defined wavelength but we only see in red, green and blue so get a mix of those.

Surely though, the capability of the receiver (us) to interpret the message (the colour) has no pertinance to the transmitter of the message or the message itself?

It's transmitted whether we are there to receive it or not.

It exists independently of us.
Our ability to interpret in one particular way doesn't define the nature of the transmission only the way we receive/understand it?

[AshVX220]

What I have wondered, and EricMc may have alluded to it earlier, is, do we all see colour the same way? We are told what red, blue, green, yellow are from an early age, but do we all actually perceive the colours the same, if I borrowed someone else's eyes/brain, would I see yellow as red for example (if you see what I mean).