Muhammad Yunus recently turned 75. But that doesn’t mean that the 2006 Nobel Peace Prize winner who founded the Grameen Bank, which gives “microcredit” loans to the poor, is thinking about retirement. In an interview with NPR he says: “The word ‘retirement’ is a very harmful word because it tells you that you have no more use left in you. You retire a ship, you have no use for it, you just put it in mothballs. A human being is not something you can mothball.” The Optimist wholeheartedly agrees.