Quidditch Through the Ages the fictional and real world it is the definitive handbook on the history and intricacies of the game. It also serves as a catalogue of the many British Quidditch teams. When Severus Snape caught Harry outside the school with this book in "Harry Potter and the Philosopher's Stone", he invented the rule that no library books were allowed outside the school, and confiscated it. In the "Harry Potter" universe, Kennilworthy Whisp is a Quidditch expert and fanatic who has written many books about the sport. He lives in Nottinghamshire, where he divides his time with "wherever the Wigtown Wanderers are
Harry Potter and the Methods of Rationality of "HPMOR" spontaneously burped itself into existence inside my mind, so it came out as a Harry Potter story. ... there's a large number of potential readers who would enter at least moderately familiar with the Harry Potter universe." He states that his work on rationality "informs every shade of how the characters think, both those who are allegedly rational and otherwise". He also used it to assist the launch of the Center for Applied Rationality, which teaches courses based on his work. Unlike J. K. Rowling's original books, in which the orphaned Harry Potter is raised by the abusive