Alice does not like the Caterpillar when they first meet, because he does not immediately talk to her and when he does, it is usually in short sentences or difficult questions. He asks Alice to repeat the poem You Are Old, Father William, which comes out rather strange like many of the nursery rhymes Alice attempts in Wonderland. The Caterpillar then tells Alice how to grow and shrink by eating the mushroom upon which he is sitting.
The original illustration by John Tenniel at right, is something of a visual paradox; the caterpillar's human face appears to be formed from the head and legs of a more realistic caterpillar.