Ten years ago, a photo of a dress posted on Tumblr sparked a massive debate: was it blue and black or white and gold? Millions argued online, and even celebrities joined in. ELI5:Why does this dress appear white gold to some people and black blue to others? : r explainlikeimfive Optical illusions: Why they work, according to science 9Honey Really quite excited about getting to wear this for filming tomorrow. Recognise it? #BBC_Colour ELI5: The science behind the blue black, white gold dress phenomenon? : r explainlikeimfive CMV: Change my view from seeing this dress as blue and black to seeing it as white and gold. : r changemyview