Jennifer Adcock asked:
Is what I call green the same for the next person? In other words, is what Iím calling green grass really the same visual experience for me as it is for, say you?
We put this question to Professor Ron Douglas:
Ron - Thatís almost a philosophical question. The first thing to say is that whatís happening in the eye in all of us is the same. We have the same chemicals. We have the same responses to the light but its what our brain makes with this information thatís different. So for instance, if you take, you know, if you were I, youíll probably be appalled to hear weíre fairly similar. If you have all chips of all different colours and you put them into different piles, we would make a pile for green, a pile for blue, a pile for yellow, a pile for red. But if you ask people for instance some African tribes whoíve had very little contact with the Western world, they will put them into different piles that they will put yellows and reds together and swear blind that theyíre the same colour and they will put blues into different piles and closer to home. Even in Welsh, there is a word called glas which encompasses what you and I would call blue but it also encompasses some things that we call green.
Chris - Wow! But if you look in the retina, the thing thatís doing the seeing and converting light waves into brain waves, is there a dramatic difference between the way the African tribes who do what youíve just described are doing that and us.
Ron - No! Thereís absolutely no difference at all in what the eye is doing but itís a difference in the brain, itís where culture comes in to play and interacts with the visual stimulus.