Hans Rosling was a worldwide celebrity because of his enthusiasm, ways of making complicated questions understandable, constantly showing how the world is improving in the face of pessimism. He was encouraging people, lifting them to new levels of understanding, hope and involvement. He passed away too early and will be missed by the many of us who believe in a better future, a humane world. A professor of the old tree, demanding, teaching but living in the new world with constant hope for the future. You can learn from him and share his heritage on his website: http://www.gapminder.org/.