If it is written as well as you can possibly write it, I will give you a quarter of a dollar.

Suppose I say this to him privately, so that none of the rest of the boys can hear, and he goes to take his seat and begins to work.

You perceive that I have presented to him a motive to exertion." "Yes, sir," say the boys, all looking with interest at the teacher, wondering how this experiment is going to end.
"Well, what would that motive be ?" "Money." "The quarter of a dollar." "Love of money," or perhaps other answers, are heard from the various parts of the room.
"Yes, love of money it is called.

Now suppose I should call another boy, one with whom I was particularly acquainted, and who I should know would make an effort to please me, and should say to him, 'For a particular reason, I want you to copy this poetry'-- giving him the same--'I wish you to copy it handsomely, for I wish to send it away, and have not time to copy it myself.

Can you do it for me ?' "Suppose the boy should say he could, and should take it to his seat and begin, neither of the boys knowing what the other was doing.