Carroll uses the rabbit hole as a metaphor for the object of a child's curiosity. In Chapter 1, Alice takes her famous tumble down the rabbit-hole:
She ran across the field after it, and fortunately was just in time to see it pop down a large rabbit-hole under the hedge. In another moment down went Alice after it, never once considering how in the world she was to get out again.
Her fall is a metaphor for chasing the objects of her curiosity and exploring the unknown. She pursues the White Rabbit immediately upon seeing him. Her unfettered enthusiasm also suggests her comparative immaturity; she "does not stop to think" before following the rabbit, nor does she ever consider how she will get out of the hole. She soon discovers that Wonderland does not offer an exit into the real world. In the same chapter, she wonders:
Down, down, down. Would the fall never come to an end? “I wonder how many miles I’ve fallen by this time?” she said aloud. “I must be getting somewhere near the centre of the earth. Let me see: that would be four thousand miles down, I think—” (for, you see, Alice had learnt several things of this sort in her lessons in the schoolroom, and though this was not a very good opportunity for showing off her knowledge, as there was no one to listen to her, still it was good practice to say it over)[...]
The presence of rational thought and academic recollections during her fall represents Alice's ability to maintain her composure despite extraordinary circumstances. She retains her composure throughout most of the story; the animals and people of Wonderland seem more afraid of her than she is of them. Her sensibility, though rational, seems sort of mad in the context of the story. Readers might ask: how does she remain so calm and collected? Perhaps the Mad Hatter's observation that "we're all mad here" is correct: every character she encounters after falling down the rabbit-hole is considered to be mad by Alice, and thus, in her curious child's point of view, they are all mad. In other words, everything the reader encounters after Alice falls down the rabbit-hole should be considered from that childlike perspective.
