NEW YORK (CBSNewYork) — Social media was abuzz Thursday night about what would appear to be an everyday photo of a two-tone dress.

Everyone agrees that the photo is of a dress featuring two colors – but Facebook, Twitter and Tumblr have blown up – complete with hashtags – over the just what those two colors are.

It all started when a woman — identified in multiple published reports as singer Caitlin McNeill of the Hebrides Islands offshore from Scotland — posted the image on Tumblr Wednesday with the question, “Is this dress white and gold, or blue and black?”

Now just about everyone is weighing in. Taylor Swift has gone with blue and black.

But the city’s global welcome ambassador might run into some disagreement up in the Bronx. The Yankees’ Jacoby Ellsbury said he sees white and gold.

Wired.com provided a scientific explanation about why people can’t agree. The publication explained that human eyes are evolved to see in daylight, but daylight changes color at different times of day.

Thus, neuroscientist Bevel Conway told the publication, the brain unconsciously tries to discount the “chromatic bias” of the daylight axis – which ranges from a stark blue and white in the midday hours to red at dawn and dusk. The result is that people discount the blue and see white and gold, or discount the gold and see blue and white, Conway explained to Wired.com.

Another theory is more philosophical in nature – if you see black and blue, you are dealing with stress in your life, while if you see white and gold, everything is fine.