About Rosie Leizrowice Rosie is currently a content writer for Farnam Street, creating thought-provoking articles and member-only content. She the co-author of the Great Mental Models book series in Berlin, Germany where she does all of her research and writing. Books by Rosie Leizrowice The Great Mental Models, Volume 3 Systems and Mathematics by (author) Shane Parrish, Rhiannon Beaubien & Rosie Leizrowice The Great Mental Models Volume 3: Systems and Mathematics by (author) Rhiannon Beaubien & Rosie Leizrowice