On Lessons, by Lewis Carroll
"And how many hours a day did you do lessons?' said Alice, in a hurry to change the subject.
Ten hours the first day,' said the Mock Turtle: 'nine the next, and so on.'
What a curious plan!' exclaimed Alice.
That's the reason they're called lessons,' the Gryphon remarked: 'because they lessen from day to day."
— Lewis Carroll (Alice's Adventures in Wonderland & Through the Looking-Glass)