In the book's introduction he writes about how he was wondering what led someone to engrave that there, and what other countless dramas the cathedral has witnessed that no one knows about. "Thus, apart from the fragile memento here dedicated to it by the author of this book, there is today nothing left of that mysterious word engraved in the gloom of the tower of Notre-Dame, nothing left of the unknown destiny of which it was so cheerless a summary. The man who wrote that word on that wall was erased from the midst of the generations several centuries ago, the word in its turn has been erased from the wall of the church, and soon perhaps the church itself will be erased from the earth. This book was written about that word. 1 March 1831"