We were told this morning that the internet had been ablaze all night with the most urgent question in the world’s history. Exactly what colour was #thedress ?
Most people thought it was blue and gold; a minority saw it as blue and black.
A quick check with the colour picker in Photoshop shows that it’s blue and black, even if it doesn’t look it. The Journal.ie produced one of the best explanations of the phenomenon.
So, we should see it as blue and black, these are the ‘correct’ colours, right?
Wrong; it’s shades of grey.
Now before you think I’ve totally lost my marbles, hear me out. We know that there are receptors called cones in the eyes; and that these are sensitive to either red, green or blue light. That’s not strictly correct; they respond to wavelengths of the electro-magnetic spectrum, those parts which we call the ‘visible spectrum’. We can’t (normally) see into the infra-red or the ultra-violet parts of the spectrum, though some animals such as raptors are able to tract small rodents by seeing their UV urine trails.
It’s now thought, though it’s clearly very hard to be certain, that what we perceive as ‘colour’ is a function of the occipital cortex of the brain, where images are processed. To make it easier for us to distinguish, say, healthy vegetables from unripe or rotten ones, we now have them ‘coloured’. We can tell when a tomato is ripe from it’s ‘colour’, as we can tell when the steak has gone bad.
It seems that there are no colours in nature, they are, in a way, a figment of our imagination. Life is just grey. Which is rather sad to know.
Robert Campbell is a retired surgeon.