there are still other things that we believe although we have not
experienced them at all. We believe that Columbus visited America in
1492, that Grant was a great general, that Washington was our first
president. Directly, these things have never been experienced by us,
but indirectly they have. Others, within whose experience these things
have fallen, have led us to accept them so thoroughly that they have
become our experience second hand.

If we are told that a man who was in the Iroquois Theater fire was
seriously burned, it seems reasonable to us because our experience
recognizes burning as the result of such a situation. But if we are
told that a man who fell into the water emerged dry, or that a general
who served under Washington was born in 1830, we discredit it because
such statements are not in accord with our experience. We are ready,
then, to answer our question: _"What reasons will those in the
audience believe?" They will believe those statements which harmonize
with their own experience, and will discredit those which are at
variance with their experience._ This experience, as we have seen, may
be first hand, or direct; or it may be indirect, or second hand.

In every case, the speaker's argument must base every issue upon
reasons that rest on what the hearers believe because of their own
direct or indirect experience. Suppose I assert: "John Quinn was a
dangerous man." Someone says: "Prove that statement." I answer: "He
was a thief." Someone says: "If that is true, he was a bad man, but
can you prove him a thief?" Then I produce a copy of a court record
which states that, on a certain day, a duly constituted court found
John Quinn guilty of robbing a bank. All my hearers now admit, not
only that he was a thief, but also that he was a dangerous person. I
have given them a reason for my statement, and a reason for that