Q. The charming illustrations by Virginia Johnson are an unexpected element that makes this book unique and fun. What gave you the idea to forego all the usual styled-room photography and go with illustrations that portray real rooms?A. I wanted the book to be a lovely and special object in itself, and Virginia’s work is magical. I also thought illustrations would help readers focus on the principles and ideas at play in the rooms, instead of getting bogged down in the particulars of the specific things that people have.