When the final Harry Potter book came out a couple of weeks ago, I found a lot of the comments left by people on articles discussing the book went something like, "Harry Potter is a children's book and I am an adult. As an adult, I don't read children's books." The obvious question about whether or not the Harry Potter series is really meant for children notwithstanding, I think this is a pretty forced piece of logic. Adults are certainly not precluded from reading children's books; in fact I like to read many books that I feel have been written for some demographic other than myself. Secondly, books that were once considered or written as juvenile literature have since become widely read by adults, like Tom Sawyer or The Hobbit. Furthermore, to write a good children's book requires a certain kind of talent for distilling information, and the kind of children's book that can tackle topics of great importance while simultaneously employing the kind of adventure and clarity to which children respond is a pretty impressive feat.
The Phantom Tollbooth isn't just one of those books; in many ways it's a book about writing that kind of book. It is an allegorical romp through the world of knowledge, and part of what its protagonist Milo learns in the land of Dictionopolis is to value clarity, brevity, and simplicity.
But more than that, The Phantom Tollbooth is a primer for young kids about the nature of knowledge itself. In it, the smart but bored-of-school Milo comes home one day to find a tollbooth (some assembly required) left for him at his door, and in his wind-up car he passes through it, ending up in a strange land. This land is split into two parts, the Kingdom of Dictionopolis, ruled over by King Azaz the Unabridged, and the Kingdom of Digitopolis, ruled over by the Mathemagician, King Azaz' brother. The kingdom has fallen into shambles since the exile of princesses Rhyme and Reason and the disagreement between the two kings about whether words or numbers are more important. Milo, with his friends the Watchdog and the Humbug, sets off through the Mountains of Ignorance to free the princesses.
The writing is so clever, and the topics so complex: One of my favorite parts is when, while traveling through the Mountains of Ignorance, the three heroes meet a character called the Terrible Trivium, who sets them to tasks like moving water from one well to another with a dropper or digging a hole through a cliff with a needle. This sort of lesson--that to live life fully, one must ignore trivial tasks and focus on important ones--is something that many adults live their entire lives without learning. That's what impresses me about this book: the whole thing tackles concepts of knowledge and learning that border on the philosophical, while being written simply enough for kids to understand.