Alice’s Adventures in Wonderland by Lewis Carroll

Charles Lutwidge Dodgson born on 27 January 1832 was better known by his pen name Lewis Carroll. He was an English writer of children's fiction, notably Alice's Adventures in Wonderland and its sequel Through the Looking-Glass. 

 In Alice’s Adventures in Wonderland by Lewis Carroll, Alice has an extremely entertaining episodic dream, but the narrator exposes this at the end of the story.  At first, Alice follows a rabbit down a rabbit hole and finds a bottle labeled “drink me” and so she does, which allows her to fit through an underground door with a golden key.  Next, she finds a cake that is labeled “eat me” and her size is restored.  She begins to cry, becomes smaller, and must swim through her own tears.  Alice begins to talk to the creatures she finds in her wonderland adventure. Each creature may sing to her, give her advice, or help her along her way.  In the novel, Alice does not have any prejudice, eats magic mushrooms that do not affect her feelings about herself in any way, and meets up with a hookah-smoking caterpillar.  One of the most helpful creatures is the Cheshire cat who steers Alice to the mad tea party and eventually leads her to the garden, where she came from.  Alice is only threatened by one character and that is the queen of hearts who threatens Alice with an “off with your head” statement.  In the end, Alice wakes up, staying away from danger, and her sister tells Alice she has been dreaming.

As other answers have suggested, a central message of the book is that of identity. Her adventures there initially literally change her physical identity—she is always growing and shrinking. This shows how difficult it can be to "fit in" to a new culture. As Alice says, before bursting into tears, "Who in the world am I?"

Alice had a much more concrete sense of self when she was in her safe, if duller, Victorian home with Dinah and her cat. 

Through the Looking-Glass to follow as I work on Flamingo interesting 55 of 2020