The dreamers of this world are the visionaries, the free thinkers with imagination. They’re individual, enormously brave and (almost) unstoppable. Look at Martin Luther King and hear that speech again. He had a dream. So did Mandela, in jail on Robbin Island. So does Polly Higgins, the barrister who wants the United Nations to identify another crime against humanity: ecocide. These dreamers don’t lie around wishing the world was kinder. They change it.