Leonardo da Vinci

Leonardo da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist, and writer. He has been referenced multiple times in the series:
 * In "I'd Rather Read It Myself" the book D.W. was pretending to read was actually about Leonardo da Vinci.
 * In "The Boy with His Head in the Clouds," he is George's Renaissance project for Mr. Ratburn's class, as George finds that Da Vinci also had dyslexia
 * His painting of the Mona Lisa is referenced in "Fifteen," when a version of it is shown with cat whiskers.