The subject of an argument must always be a complete statement. The reason for this requirement lies in the fact that an argument can occur only when men have conflicting opinions about a certain thought, and try to prove the truth or falsity of this definite idea. Since a _term_--a word, phrase, or other combination of words not a complete sentence--suggests many ideas, but never stands for one particular idea, it is absurd as a subject to be argued. A debatable subject is always a _proposition_, a statement in which something is affirmed or denied. It would be impossible to uphold or attack the mere term, "government railroad supervision," for this expression carries with it no specific thought. It may suggest that government railroad supervision has been inadequate in the past; or that government supervision is at present unnecessary; or that the government is about to assume stricter supervision. The term affords no common ground on which the contestants would have to meet. If, however, some exact idea were expressed in such a statement as, "Further government railroad supervision is necessary for the best interests of the United States," an argument might well follow.

Although the subject of an argument must be a complete thought, it does not follow that this proposition is always explicitly stated or formulated in words. The same distinction between subject and title that exists in other kinds of writing is found also in argumentation; the subject is a statement of the matter about which the controversy centers; the title is the name by which the composition is known. Sometimes the subject serves as the title, and sometimes the subject is left to be discovered in the body of the work. The title of the speech delivered by Webster in the Senate, January 26, 1830, is "Webster's Reply to Hayne"; the subject, in the form of a resolution, is found close to the opening sentences:--

_Resolved_, That the Committee on Public Lands be instructed to inquire and report the quantity of public lands remaining unsold within each State and Territory, and whether it be expedient to limit for a certain period the sales of the public lands to such lands only as have heretofore been offered for sale, and are now subject to entry at the minimum price. And, also, whether the office of Surveyor- General, and some of the land offices, may not be abolished without detriment to the public interest; or whether it be expedient to adopt measures to hasten the sales and extend more rapidly the surveys of the public lands.