Harry Potter and the perfect number
There is one point in the latest book of the Harry Potter series, Harry Potter and the half Blood Prince, that we discover that seven is a very magical and perfect number in the wizarding world. No wonder J.K. Rowling left half of the story out of the latest edition for it to be completed in the final seventh book.
Don't misunderstand me, I enjoyed reading the book; once I waited for my eager 10 year old to complete it first. However I really did feel, more than any of the other books, that this book had two purposes, the greater of which was the setting up of the final chapter in this epic adventure, book number seven.
I look forward to the next installment where the story will hopefully come to a conclusion if not end.