Colour. While nearly every human being on this planet knows what it is, it’s still a very abstract idea. For starters, let’s conduct a short thought experiment. Take a second to focus on the colours you see right now. Look at the clothes you are wearing (let’s assume you are not reading this butt naked). Try and describe the colour you see. First thing that probably pops into your mind is the word associated with that colour – in my case this would be grey. Now try and describe that colour without mentioning the word associated with it. How would I describe the colour grey? Well I could say that my t-shirt is the same colour as ashes are. Or perhaps point at something and say that my t-shirt is that colour. But no matter how long you try it’s nearly impossible to describe the colour you see without comparing it to something else or using the word associated to it.
Few days ago I was discussing this with Marais and Sims. This topic was always one of those ‘mind fuck’ topics which I love to think about and discuss with others. But in order for me to present you with my personal ‘theory’ I feel the need to explain briefly what colours really are.
Colour is your brain’s personal interpretation of light that has reached your eye. In a way, we see the world with with our brains, not our eyes. Light that reaches your eye has a certain wavelength, or should I say a range of wavelengths. That range of wavelengths is a factor which decides what colour we perceive. For example, visible blue light has a wavelength of around 475 nano metres.
When a packet of light strikes your eye, your body detects few things – some of which is the angle at which the light comes in and the wavelength (keep in mind that light behaves both as particles and waves). That data is then transferred to your brain where it is then interpreted. Your brain analyses all the values corresponding to the angles to ‘paint’ an image. The easiest way of imagining it is to think of a computer screen. An image on your screen is divided into pixels – for example my monitor displays 1920×1080 pixels. Now imagine that your brain associates each of these data inputs – packets of light – as one pixel. The angle helps your brain to place that pixel in the correct place.
Okay, but what does that have to do with what colour is? Well, your brain associates a certain wavelength with a given ‘pixel’ (bear in mind that we do NOT see in pixels – I’m only using this terminology to help visualize my point). This results in your brain seeing an image as a lot of numbers placed on a grid. In order to understand this, it has to associate these numbers with a colour. For example every ‘pixel’ with a value of 475 nm will be blue.
But does blue look like? For you the answer is simple – as soon as you think of the word blue an image pops in your head, an image that corresponds to the wavelength of 475 nm. But is my blue the same as your blue? Do I see the world the same way that you do?
This is how I like to think about it. Our brains are very much unique and personal. While its general anatomy might be very similar to other brains, it’s ‘coding’ will be significantly different to someone else’s brain. The brain is essentially a biological computer – therefore I like to explain these concepts using computing terminology.
To be able to interpret the wavelength of light and display it as an image your brain needs some sort of a decryption key. That decryption key will associate a numerical value of 475 nm with an image that you perceive as blue. Now, because our brains are so much different, our decryption keys are most likely completely different as well. This means that what I perceive as blue you probably can’t even imagine. Or maybe what I see as red you might see as green. Obviously we all know that trees are green – as kids we were taught that the image you perceive when you see a tree is called green. But that doesn’t mean that my green doesn’t look like your black.
It’s a very strange concept to understand. The reason we manage to agree that an object is a certain colour because it will always give out light of a certain wavelength – that is constant. What isn’t constant is our perception of that colour.
Before I bore you to death with my ramblings allow me to make one last point. In order to find out whether what I perceive as red is the same as what you do we would need to ‘exchange’ our decryption keys. Of course that is a completely abstract idea. But in theory that and only that would allow you to see the world the way the other person does. In some way we are alone in what we perceive. No one else may possibly share that image when you watch a beautiful sunset – not even if they are there to watch it with you.
This is also why I believe different people tend to like different colours. While you might love the colour purple I might simply hate it – all of it because what you see as purple and what I see as purple are totally different.
TL;DR – We all most likely experience totally different images when we think of the same colour. This might be because my brain will ‘decrypt’ lights wavelength in a different way to your brain. This might also be why different people like different colours. You might love the image that you perceive when you see purple, I might hate it. This is because my image that’s associated with purple is probably totally different to yours.