It is one thing for philosophers to talk about colour. They are often dismissed as not in touch with reality. But when a scientist speaks people take notice. Colour has always been a mystery to me, the way it is not really a part of the external world and only manifests in the conscious mind. How can that situation come about?
I recently watched a fascinating television programme about the effect of visual ailments on the work of artists (The Disordered Eye, BBC 4 November 2020, presented by disabled artist and film-maker, Richard Butchins). He interviewed Professor of Neuroscience at the University of Sussex, Anil Seth. This is what the Professor had to say about colour:
‘…colours are just mixtures of different wavelengths of light and the brain is generating colours from mixtures of these wavelengths… It’s not just that the brain is taking into account and compensating for ambient light. It’s that colours themselves are constructions of the brain all the time. There’s no physical truth to the fact that the tomato is red. Redness is a property of our conscious experience, a property of our perception. It’s not a property that’s inherent to the tomato… the reason the brain had invented the ability to perceive colour is precisely so we can track keep track of objects as ambient lighting conditions change. So colours are a very useful trick. They show that what we perceive is in one sense less that what’s out there. And we know it’s less because our eyes are only sensitive to three specific wavelengths in the electromagnetic spectrum. The brain brings something fundamental to the act of perception. It’s not just reading out what’s already there but it is entirely dependent on what’s out there too.’
I take issue with one or two points. He takes for granted the notion that the brain ‘generates’ colours. There may be an incredible amount of activity going on among billions of neurons in the brain. They are constantly passing messages to one another along many more billions of connections among them but, as far as I can see, they do not do any generating of conscious experiences. Which leads into the next very similar point. One moment Professor Seth talks about colour in terms of ‘conscious experience’ but a little later colour seems to be a feature of the brain. This fudging of terms is very common and does not take into account the clear distinction between the properties of consciousness and those of materiality of which the brain is an instance.
Consciousness and Other Matters 