Seeing Colors

Like the author of this article, I have often wondered if the green I see is the same as the green another person sees. How can we know we see the same thing even when we call it green. It is hard to accept that people may see the color differently and still call it the same thing. It calls into question the small core of things we hold to be universal.

The notion that pain varies between individuals does not disturb us. Why, then, do we resist the idea that different people see different colours?

Whereas the sensation of pain is related to individual tolerance for it and it makes sense that people feel different intensities, the same is not true about colors. As the author points out :

There is a lawfulness to colour, and it would help if we knew where this lawfulness resided

If red and green did not have the same universal connotation, they could not be used to traffic lights. My green being your red would just not work. Yet my green is likely a little different from yours.

Synaesthesia may simply be an exotic manifestation of something we all enjoy: the ability to turn sensations into symbols, and to think with them. After all, if our thoughts are not made of sensations, what are they made of? And this is why we find it so distressing, you and I, to realise that we don't see the same colours. Colours - so striking, so beautiful, so manifestly there - are one of the few things we can agree on, more or less. How cast adrift will we feel if colours turn out to be, after all, only our thoughts about light?