My question is when people see colours do they actually see the same thing? You are told from birth that the sky is blue and the grass is green, so you learn names for the colours you perceive. But if you could somehow get into another person's brain and see what they see, would the colours be the same at all? Or would red for you be green for them?

I'm not sure if the answer will ever be known. On the aforementioned radio station, there was mention of the fact that different peoples can perceive different shades, and women can actually perceive different than men. However, the core question remains unanswered...

Likewise something that's painted in vivid red and orange: the same wavelength of light is stimulating the rods and cones in your eyes and my eyes, but how our brain interprets that is a unique, personal experience. What is know is that to most people from a western culture these colours are far more "stimulating" than most others.

Our understanding of colour is also very open to cultural bias. Many people know that to the Chinese white is a colour that signifies death, whereas black has this symbolism in Western cultures. Yet even amongst people from the same region there is variation: the Welsh have a word glas that basically translates as "the colour of a mountain lake" -- dependent on the ambient lighting this can be anything from grey through deep green to a vivid blue. In the Welsh language these shades all count as one colour, glas, whereas English distinguishes between them.

No people dont see the same thing when they see colours (I will stick to the UK English Spelling).

This is shown up in Colour Blindness, I am Colour Blind in the Turquoise area (Blue/Green). Its not that I cannot see anything that is Turquoise in Colour, but unlike people who claim that it is an individual colour all I see is a shade of Blue or Green not a mix of both.

So what I see as one colour, the majority of people see as another.

This is not a problem with my eyes (since they can see the turquoiuse frequency of light), but more of a question of recognition that this frequency is in fact a distinct colour.

Heres an Experiment to prove my point.

Gather a dozen people together at sunset and ask them what Colour it is.

I believe that the majority if pressed will not be able to give a precise answer that is the same as their neighbours.

While we are all conditioned to recognize colors the same, I would agree that no two people see things exactly the same.

The light may stimulating my rods and cones the same as it does yours, but does your eye have the exact same ratio of rods/cones so that it is capable of interpreting the signal in exactly the same fashion? I am willing to entertain the thought that there are a myriad of differences, and that only our common cultural acceptance drives shared color identification. Color (or colour) blind individuals just punctuate this for the rest of us, with their rods/cones behaving in such a radically different fashion