worked in schools (X) and (Y).

_If the experience of the audience_ is that these men are untruthful
or likely to exaggerate, our evidence will not be good evidence. If
the experience of the audience is that these men are capable, honest,
and reliable, this evidence will go far toward gaining acceptance of,
and belief in, our proposition.

Many attempts have been made to put evidence into different classes
and to give tests of good evidence. There is but one rule that the
debater needs to use: _In judging evidence for a debate consider what
the effect will be on the audience and the judges. Will it be
convincing to them_? In other words, will it make their own experience
quickly and strongly support the issues?

Time is always limited in a debate. The wise debater will then choose
that evidence which will most quickly make his hearers feel that their
own experience proves him right. When the speaker has done this, he
has chosen the best evidence and has used enough of it.

In courts of law where witnesses appear in every case and testify as
to circumstances that did or did not occur, it is necessary that the
jury be able to distinguish carefully between what it should and
should not believe. Witnesses often have a keen personal interest in
the verdict and, therefore, are inclined to tell less or more than the
truth. Sometimes witnesses are relatives of persons who would suffer
if the case were decided against them and they have a tendency to give
unfair testimony.

In order that the jury may decide as fairly as possible what evidence
is sound and what is not, the attorneys on each side of the case make
out a copy of what are called instructions. These are given to the
judge who, provided he approves of them, reads them to the jury.
Usually these instructions urge the jurors to consider four things.
They must consider, first, whether or not the statements of the
witness are probable; that is, are they consistent with human
experience? Do they seem reasonable and natural? A second thing which
the jury is told to bear in mind is the opportunity which the witness
had of observing the facts of which he speaks. Was he in a position to
be familiar with the thing he describes? In this connection, the jury
is sometimes instructed to consider the physical and mental qualities
of the witness. Is he a man who is physically and mentally able to
judge what he observes under such circumstances? A third factor which
the jury mus