Dictionopolis was a city built entirely on the power and beauty and importance of the spoken and written word.
Digitopolis was a city built with equal conviction on the precision and elegance and necessity of numbers.
The citizens of each city regarded the other with a mixture of pity and barely concealed contempt.
Milo walked through both cities and noticed something that the citizens themselves had long since stopped noticing.
The bread sold in Dictionopolis required a recipe with measurements — without numbers it could not be made properly.
The roads built in Digitopolis required signs with words — without language no one could know where they were going.
Each city desperately needed the thing it most disdained in order to function at its most basic level at all.
Words and numbers matter — the world needs them together.

Juster uses the geography of the Lands Beyond to make an epistemological argument in the most concrete terms possible.
Dictionopolis and Digitopolis are not merely settings — they are embodiments of two complementary modes of understanding.
Language gives us the ability to name, narrate, persuade, and imagine — to make meaning from experience.
Mathematics gives us the ability to measure, predict, verify, and build — to impose order on the physical world.
A civilization that possessed only one of these capacities would be like a person with only one hand.
It could accomplish some things but would be permanently disabled in ways that became more evident with each new challenge.
The princesses Rhyme and Reason represent the synthesis that makes both capacities fully operational and mutually reinforcing.
Their rescue is not merely a plot device — it is the story's argument for integrated thinking over narrow specialization.
Words and numbers matter — the world needs them together.