to convince
another of the error of his beliefs. Men continually use the words
_because_ and _therefore;_ indeed, a great deal of writing has in it
an element of argument.

From the fact that argument and exposition are so nearly alike, it
follows that they will be governed by much the same principles. As
argument, in addition to explaining, seeks to convince, it is
necessary, in addition to knowing how to explain, to know what is
considered convincing,--what are proofs; and secondly, what is the
best order in which to arrange proofs.

Induction and Deduction.

Arguments have been classified as inductive and deductive.[22]
Induction includes arguments that proceed from individual cases to
establish a general truth. Deduction comprises arguments that proceed
from a general truth to establish the proposition in specific
instances, or groups of instances.

Syllogism. Premises.

If one should say "Socrates is mortal because he is a man," or
"Socrates will die because all men are mortal," or "Socrates is a man,
therefore he will die," by any of these he has expressed a truth which
all men accept. In any of these expressions are bound up two
propositions, called premises, from which a third proposition, called
a conclusion, is derived. If expanded, the three propositions assume
this form: All men are mortal. Socrates is a man. Therefore Socrates
is mortal. This is termed a syllogism. A syllogism consists of a major
premise, a predication about all the members of a general class of
objects; a minor premise, a predication that includes an individual or
a group of individuals in the general class named by the major
premise; and a conclusion, the proposition which is derived from the
relation existing between the other two propositions. The propositions
above would be classified as follows:--

Major premise: All men are mortal, a predication about _all_
men.

Minor premise: Socrates is a man, including an individual in
the general class.

Conclusion: Socrates is mortal.

Terms.

In every syllogism there are three terms,--major, minor, and middle.
The middle term is found in both the premises, but not in the
conclusion. It is the link connecting the major and minor terms. The
major term is usually the predicate of the major premise and the
predicate of the conclusion. The minor term is the subject of the
minor premise and the subject of the conclusion. "Men" is the middle
term, "are