The Dress: Black and Blue or White and Gold? Long Black Sweetheart Prom Dress with Gold Trim PromGirl Neuroscientists Explain Discrepancy Behind "The Dress" Illusion Here's why people saw the dress differently. The dress is black & blue, but here's why you can't tell TJ Kelly In 2015, a photograph of a dress went viral, dividing viewers over whether its colors were blue and black or white and gold. This optical illusion highlighted differences in human color perception