… growing gap between rich and poor. Taking a cue from Thomas Picketty, author of ' Capital in the 21st century ', speakers predicted that the … pay. In the 1960s, marginal tax rates on the richest households were more than 80 per cent, with apparent broad consensus that wealthier … up behind Warren Buffett and demand that they pay their fair share. Camilla Toulmin ( camilla.toulmin@iied.org ) is IIED's director. … …