How can people live together peacefully, especially in a multicultural, multi-religious society? We should find a minimum level of consensus which is needed to live peacefully together in an open (world) society and a moral language to communicate with each other. Dutch philosopher Paul Cliteur published his book Moral Esperanto (this book is in Dutch and has not yet been translated) in 2007 in which he argues that it is important that people can communicate with each other in a moral and political language which is in principle understandable to everybody; in contrast with religious discourse which only makes sense to believers. Cliteur makes the analogy of Esperanto, the artificial language proposed to be the lingua franca, and emphasizes the need for a universal moral language.