Growth into Adulthood
This theme is central to both books. Alice's adventures parallel the journey from childhood to adulthood. She comes into numerous new situations in which adaptability is absolutely necessary for success. She shows marked progress throughout the course of the book; in the beginning, she can barely maintain enough composure to keep herself from crying. By the end of the novel, she is self-possessed and able to hold her own against the most baffling Wonderland logic.
Size change
Closely connected to the above theme, size change is another recurring concept. The dramatic changes in size hint at the radical changes the body undergoes during adolescence. The key, once again, is adaptability. Alice's size changes also bring about a change in perspective, and she sees the world from a very different view. In the last trial scene, her growth into a giant reflects her interior growth. She becomes a much stronger, self-possessed person, able to speak out against the nonsensical proceedings of the trial.
Death
This theme is even more present in the second Alice book, Through the Looking Glass. Alice frequently makes references to her own death without knowing it. Childhood is a state of peril in Carroll's view: children are quite vulnerable, and the world presents many dangers. Another aspect of death is its inevitability. Since the Alice books are at root about change (the transition from childhood to adulthood, the passage of time), mortality is inescapable as a theme. Death is the final step of this process of growth. While death is only hinted at in the first book, the second book is saturated with references to mortality and macabre humor.
Games/ Learning the Rules
Every new encounter is something of a game for Alice; there are rules to learn, and consequences for learning or not learning those rules. Games are a constant part of life in Wonderland, from the Caucus race to the strange croquet match to the fact that the royal court is a living deck of cards. And every new social encounter is like a game, in that there are bizarre, apparently arbitrary rules that Alice has to master. Learning the rules is a metaphor for the adaptations to new social situations that every child makes as she grows older. Mastering each challenge, Alice grows wiser and more adaptable as time goes on.
Language and Logic/Illogic
Carroll delights in puns. The Alice books are chockfull of games with language, to the reader's delight and Alice's confusion. The games often point out some inconsistency or slipperiness of language in general and English in particular. The books point out the pains and advantages of language. Language is a source of joy and adaptability; it can also be a source of great confusion.
Just as baffling is the bizarre logic at work in Wonderland. Every creature can justify the most absurd behavior, and their arguments for themselves are often fairly complex. Their strange reasoning is another source of delight for the reader and challenge for Alice. She has to learn to discern between unusual logic and utter nonsense.
