Answer:
I run up and down the stairs without moving. What am I?
I am what one cannot keep, two cannot hold, and three cannot destroy. What am I?
I am useless when together but useful when I am broken apart. What am I?
I am a cave full of bones and the house of a worm.
I have no voice but I can teach you all there is to know. I have spines and hinges but I am not a door. Once I’ve told you all I cannot tell you more.
What made Cyclops quit teaching?