proceedings.  Lincoln argued a proposition of fact when he took Douglas’s statement, “Our fathers, when they framed the government under which we live, understood this question just as well, and even better, than we do now,” and then proved by telling exactly how they voted upon every measure dealing with slavery exactly what the thirty-nine signers of the Constitution did believe about national control of the practice.  Courts of law demand that pleadings “shall set forth with certainty and with truth the matters of fact or of law, the truth or falsity of which must be decided to decide the case.”

Propositions of Policy.  Notice that the other proposition—­Missionaries should not be sent to China—­is not concerned with a fact at all.  It deals with something which should or should not be done.  It deals with future conduct.  It depends upon the value of the results to be secured.  It looks to the future.  It deals with some principle of action.  It is a question of expediency or policy.  It induces argument to show that one method is the best or not the best.  Propositions of expediency or policy are those which confront all of us at every step in life.  Which college shall a boy attend?  What kind of work shall a woman enter?  How large shall taxes be next year?  Which candidate shall we elect?  How shall we better the city government?  How shall I invest my money?  What kind of automobile shall I buy?  What kind of will shall I make?

The answers to all such questions make propositions of expediency or policy upon which arguments are being composed and delivered every day.

In choosing propositions for argument avoid, 1, those which are obviously truth; 2, those in which some ambiguous word or term covers the truth; 3, those in which the truth or error is practically impossible of proof; 4, those involving more than one main issue; 5, those which do not interest the audience.

Wording the Proposition.  The proposition should be accurately worded.  In law if the word burglary is used in the indictment, the defense, in order to quash the charge, need show merely that a door was unlocked.  The phrasing should be as simple and concise as possible.  The proposition should not cover too wide a field.  Although these directions seem self-evident they should be kept in mind continually.

When the proposition is satisfactory to the maker of the argument he is ready to begin to build his proof.  In actual speech-making few arguments can be made as convincing as a geometrical demonstration but a speaker can try to make his reasoning so sound, his development so cogent, his delivery so convincing, that at the end of his speech, he can exclaim triumphantly, “Quod erat demonstrandum.”