ay swear
positively to one or both of these points. The psychologist can show the
court the limitations of the witness in making such estimates.

Psychology can be of service in the examination of the criminal himself.
Through association tests and in other ways, the guilt or innocence of
the prisoner can often be determined, and his intellectual status can
also be determined. The prisoner may be insane, or feeble-minded, or
have some other peculiar mental disorder. Such matters fall within the
realm of psychology. After a prisoner has been found guilty, the court
should have the advice of the clinical psychologist in deciding what
should be done with him.

It should be added that the court and not the attorneys should make use
of the psychologist. Whenever a psychologist can be of service in a case
in court, the judge should summon such assistance, just as he should if
expert chemical, physical, physiological, or anatomical knowledge should
be desired.

A knowledge of human nature can be of much service to society in the
prevention of crime. This will come about from a better knowledge of the
psychological principles of habit-formation and moral training, through
a better knowledge of how to control human nature. A large percentage of
all crime, perhaps as much as forty per cent, is committed by
feeble-minded people. Now, if we can detect these people early, and give
them the simple manual education which they are capable of receiving, we
can keep them out of a life of crime.

Studies of criminals in reform schools show that the history of many
cases is as follows: The person, being of low mentality, could not get
on well at school and therefore came to dislike school, and consequently
became a truant. Truancy led to crime. Crime sent the person to the
court, and the court sent the person to the state reformatory.

The great duty of the state is the prevention of crime. Usually little
can be done in the way of saving a mature criminal. We must save the
children before they become criminals, save them by proper treatment.
Society owes it to every child to do the right thing for him, the right
thing, whether the child is an idiot or a genius. Merely from the
standpoint of economy, it would be an immense saving to the state if it
would prevent crime by the proper treatment of every child.

=Business.= The contribution of psychology in this field, so far, is in
the psychology of advertising and salesmanship, both hav