It’s tearing apart relationships, causing arguments between friends, and making people question everything they’ve ever learned about colors. What could possibly be causing all of this unrest? The simple answer: a dress.

It is a dress made out of blue material with black lace that was posted on Tumblr by a British woman named Caitlin McNeill. McNeill, along with her friends, could not agree on the true color of the dress.  Although the dress is really blue and black, some people see it as white and gold. Speculations spread about the real meaning behind all of the confusion. Some claimed that people who are stressed out see blue and black, while people without worries will see white and gold. It has also been said that depressed or negative people see blue and black, while people with a more positive outlook will see white and gold.

All of these claims, however, are false. There’s a lot more to this trick of the eye, and it has to do with the science of perception and the way the human brain accounts for color. Wired.com gives a clear explanation:

“Light enters the eye through the lens—different wavelengths corresponding to different colors. The light hits the retina in the back of the eye where pigments fire up neural connections to the visual cortex, the part of the brain that processes those signals into an image…Without you having to worry about it, your brain figures out what color light is bouncing off the thing your eyes are looking at, and essentially subtracts that color from the “real” color of the object…Usually that system works just fine. This image, though, hits some kind of perceptual boundary. That might be because of how people are wired. Human beings evolved to see in daylight, but daylight changes color. That chromatic axis varies from the pinkish red of dawn, up through the blue-white of noontime, and then back down to reddish twilight. ‘What’s happening here is your visual system is looking at this thing, and you’re trying to discount the chromatic bias of the daylight axis,’ says Bevil Conway, a neuroscientist who studies color and vision at Wellesley College. ‘So people either discount the blue side, in which case they end up seeing white and gold, or discount the gold side, in which case they end up with blue and black.’”

It’s almost impossible to believe that a picture of a dress could cause such a widespread explosion of popularity on the internet. Celebrities like Taylor Swift, Anna Kendrick and Demi Lovato have weighed in on its true colors. The picture has been circulating endlessly on sites like Facebook, Twitter and Buzzfeed. So, why are people so adamant about arguing over a color of a dress? Perhaps it has drawn so much attention because it’s not an argument over race, religion, or politics. It’s something that is ingrained in each of us that we can’t change, a part of our human nature that can be disputed but never altered.

Don’t believe us? Check out Wired’s explanation here.