scourse
is not description but narration.

Suppose, then, that your father should say: "Now tell me this: What is
the difference between the discovery of America and the colonization
of America?" You would now have a new task. You would not care to make
him see any particular scene or live through the events of discovery
but to make him _understand something which you understand_. You would
show him that the discovery of America meant merely the fact that
America was found to be here, but that colonization meant the coming,
not of the explorers, but of the permanent settlers. This form of
discourse which makes clear to someone else an idea that is already
clear to us is called exposition.

And now suppose your father should say: "Well, you have told me a
great deal which I may say is interesting enough, but it seems to me
rather useless. What is the purpose of all this study? Why have you
spent so much time learning of this one event?" You would of course
answer: "Because the discovery of America was an event of great
importance."

He might reply: "I still do not believe that." Then you would say:
"I'll prove it to you," or, "I'll convince you of it." You would then
have undertaken to do what you are now trying to learn how to do
better--to argue. _For argumentation is that form of discourse that we
use when we attempt to make some one else believe as we wish him to
believe._ "Argumentation is the art of producing in the mind of
someone else a belief in the ideas which the speaker or writer wishes
the hearer or reader to accept."[1]

You made use of argumentation when you urged a friend to take the
course in chemistry in your school by trying to make him believe it
would be beneficial to him. You used argumentation when you urged a
friend to join the football squad by trying to make him believe, as
you believe, that the exercise would do him good. A minister uses
argumentation when he tries to make his congregation believe, as he
believes, that ten minutes spent in prayer each morning will make the
day's work easier. The salesman uses argumentation to sell his goods.
The chance of the merchant to recover a rebate on a bill of goods that
he believes are defective depends entirely on his ability to make the
seller believe the same thing. On argumentation the lawyer bases his
hope of making the jury believe that his client is innocent of crime.
All of us every day of our lives, in ordinary conversation, in our
letter