Stefan Klein, PhD, has studied physics and analytical philosophy, and holds a doctorate in biophysics. After several years as an academic researcher, he turned to writing about science for a general audience. From 1996 to 1999, he was an editor at Der Spiegel, Germany’s leading news magazine, and in 1998 he won the prestigious Georg von Holtzbrinck Prize for Science Journalism. Today, Klein is recognized as one of Europe’s most influential science writers and journalists. His interviews with the world’s leading scientists are a regular feature in Germany’s Zeit magazine. His books, which have been translated into more than twenty-five languages, include the international bestseller The Science of Happiness, as well as The Secret Pulse of Time, and Leonardo’s Legacy. A frequent speaker and university guest lecturer, he lives with his family in Berlin.