CHAPTER VI
ARGUMENT
Argument has been defined as that form of discourse the purpose of which is to convince the reader of the truth or falsity of a proposition. It is closely allied with exposition. To convince a person, it is first necessary that the proposition be explained to him. This is all that is necessary in many cases. Did men decide all matters without prejudice, and were they willing to accept the truth at any cost, even to discard the beliefs that have been to them the source of greatest happiness, the simple explanation would be sufficient. However, as men are not all-wise, and as they are not always “reasonable,” they are found to hold different opinions regarding the same subject; and one person often wishes 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 [129] 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 [130] and the subject of the conclusion. “Men” is the middle term, “are mortal” the major term, and “Socrates,” the minor term.
Enthymeme. It is rarely the case in literature that the syllogism is fully stated: generally one of the premises is omitted. Such a form of statement is termed an enthymeme. “Socrates will die because all men are mortal” is an enthymeme. The minor premise has been omitted. “Socrates is mortal because he is a man” is also an enthymeme, because the major premise which states that “all men are mortal” has been omitted.
The conclusions arrived at by means of syllogisms are irresistible, provided the form be correct and the premises be true. It is impossible here to discuss the forms of syllogisms; they are too many. It will be of value, however, to call attention to a few of the commonest errors in syllogisms.