Often a simple explanation is sufficient to convince.  As soon as the reader understands the real meaning of a proposition, he accepts our view of the case.  A heated discussion may end with the statement, “Oh, if that is what you mean, I agree with you.”  In Section 70, we have learned that the first step in argument is explanation, by which we make clear the meaning of the proposition the truth of which we wish to establish.  This explanation may include both the expounding of the terms in the proposition and the explanation of the proposition as a whole.

There is another difference between exposition and argument.  We cannot argue about single terms, though we may explain them.  We may explain what is meant by the term elective studies, or civil service; but an argument requires a proposition such as, Pupils should be allowed to choose their own studies, or, Civil Service should be established.  Even with such a topic as Expansion or Restricted Immigration, which seems to be a subject of argument, there is really an implied proposition under discussion; as, The United States should acquire control of territory outside of its present boundaries; or, It should be the policy of our government to restrict immigration.  We may explain the meaning of single terms or of propositions, but in order to argue, we must have a proposition either expressed or implied.

+171.  Proposition of Fact and Proposition of Theory.+—­Some propositions state facts and some propositions state theories.  Every argument therefore aims either to prove the occurrence of a fact or the truth of a theory.  The first would attempt to show the actual or probable truth of a specific proposition; for example:—­

  Nero was guilty of burning Rome. 
  Joan of Arc was burned at the stake. 
  Barbara Frietchie actually existed. 
  Sheridan never made the ride from Winchester. 
  Homer was born at Chios.

The second would try to establish the probable truth of a general theory; for example:—­

  A college education is a profitable investment. 
  Light is caused by a wave motion of ether.

+172.  Statement of the Proposition.+—­The subject about which we argue may be stated in any one of the three forms discussed in Section 74; that is, as a declarative sentence, a resolution, or a question.  The statement does not necessarily appear first in the argument, but it must be clearly formulated in the mind of the writer before he attempts to argue.  Before trying to convince others he must know exactly what he himself believes, and the attempt to state his belief in the form of a proposition will assist in making his own thought clear and definite.

If we are going to argue concerning elective studies, we should first of all be sure that we understand the meaning of the term ourselves.  Then we must consider carefully what we believe about it, and state our proposition so that it shall express exactly this belief.  On first thought we may believe the proposition that pupils should be allowed to choose their own studies.  But is this proposition true of pupils in the grades as well as in the high schools?  Or is it true only of the upper classes in the high school or only of college students?  Can you state this proposition so that it will express your own belief on the subject?