It’s amazing what tricks your brain can play on you. I’m pretty sure that the diamond being moved around in this video has just one colour. But, as this optical illusion demonstrates, the brain likes to see order and pattern in the world around it and so it recolours the diamond cut out for you so that it fits into its perception of what the world should look like…. what else is it doing for me?!
Thanks to John Nack for this.