Stefan Klein

About the Author

Stefan Klein is an award-winning European science writer and author of the international bestsellers The Science of Happiness and The Secret Pulse of Time. He lives in Berlin, Germany.

Stephen Lehmann is the humanities librarian at the University of Pennsylvania. He co-translated Nietzsche’s Human, All too Human and is the co-author of Rudolf Serkin: A Life. He lives in Swarthmore, PA.