Do colours exist in the world, or are they only produced by the mind? When we got asked this question during the Glasgow Science Festival, I realised I had no idea. According to Dr David Simmons, psychology lecturer at the University of Glasgow, colour is a creation of the brain – evolution’s way of giving us useful data. How else could you account for the mistaken perception of an object’s colour as constant even under a different light? How else is it possible that some objects seem to change colour depending on their surroundings?
Colour is fickle and still not fully understood, similarly to the workings of our brains. Nature seems to have given our eyes and brains the ability to create colour so as to give us a better grasp of the world’s boundaries and shapes. However, Professor Fiona Macpherson pointed out the problems of this view: just because colour initiates many illusions, doesn’t keep the property from existing. Just because we see parallel lines as crooked on certain optical illusions, doesn’t mean that those parallel lines don’t exist. It would be perfectly valid to consider that colour exists in the world. The differences in its perception could just be explained by each individual only being able to interpret and see part of it, depending on what sensors our eyes contain.
They asked us again whether colour occurs before or after the retina. But where was an option conciliating these two alternatives? Colour could just as well be an existing property in the world, which every brain recreates in unique ways for each individual and every species. Is my colour the same as yours?