Conviction.  What should be the first requisite of a speaker of argumentation?  Should it be conviction in the truth or right of the position he takes and the proposition he supports?  At first thought one would answer emphatically “yes.”  A great deal of discredit has been brought upon the study of argumentation by the practice of speakers to pretend to have opinions which in reality they do not sincerely believe.  The practical instance is the willingness of paid lawyers to defend men of whose guilt they must be sure.  Such criticism does not apply to cases in which there are reasonable chances for opposing interpretations, nor to those cases in which our law decrees that every person accused of crime shall be provided with counsel, but to those practices to which Lincoln referred when he recommended the lawyer not to court litigation.  Nor should this criticism deter a student of public speaking from trying his skill in defense of the other side, when he feels that such practice will help him in weighing his own arguments.  In every instance of this highly commendable double method of preparation which the author has seen in classrooms, the speaker, after his speech has been commented upon, has always declared his real position and explained why he advocated the opposite.  Even school and college debating has been criticized in the same way for becoming not an attempt to discover or establish the truth or right of a proposition, but a mere game with formal rules, a set of scoring regulations, and a victory or defeat with consequent good or bad effects upon the whole practice of undergraduate debating.  If such contests are understood in their true significance, as practice in training, and the assumption of conviction by a student is not continued after graduation so that he will in real life defend and support opinions he really does not believe, the danger is not so great.  The man who has no fixed principles, who can argue equally glibly on any side of a matter, whose talents are at any man’s command of service, is untrustworthy.  Convictions are worthy elements in life.  A man must change his stand when his convictions are argued away, but the man whose opinions shift with every new scrap of information or influence is neither a safe leader nor a dependable subordinate.

For the sake of the training, then, a student may present arguments from attitudes other than his own sincere conviction, but the practice should be nothing more than a recognized exercise.

Because of its telling influence upon the opinion of others let us, without further reservation, set down that the first essential of a good argument is the ability to convince others.  Aside from the language and the manner of delivery—­two elements which must never be disregarded in any speech—­this ability to convince others depends upon the proof presented to them in support of a proposition.  The various kinds and methods of proof, with matters closely related to them, make up the material of this chapter.