Subject, matter, subject matter, argument, topic, text, theme, motive, motif, leitmotiv can mean the basic idea or the principal object of thought or attention in a discourse or artistic composition.
Subject is the most widely applicable as well as the least definite in denotation of these words; it implies merely some restriction in one’s field of choice and a governing principle determining the selection of one’s material and demanding some concentration in the treatment of it (as in a discourse or work of art).
Matter and the more usual subject matter are often used as close synonyms of subject . As often, however, these terms refer not to the idea, object, or situation selected for treatment but to a restricted field or range of material from which one selects the specific subject he intends to treat.
Argument (see also REASON ARGUMENT 2 ) can denote the subject, especially the carefully delimited subject, for a particular discourse (as a poem or a part of a poem) that is planned in advance of execution. The word sometimes implies explicit statement of the leading idea or a summarizing of its development.
Topic applies to a subject, usually of general interest, chosen because of its possibilities for individual or original treatment or for discussion by different persons holding diverse views.
Text can mean a verse or passage, usually from Scripture, chosen as providing or suggesting a subject for a sermon or similar discourse. In extended use it is often applied to whatever suggests itself as a good starting point for a discourse the subject of which is yet to be defined or which lacks a definite subject.
Theme denotes a subject which one selects for literary or artistic treatment; it is applicable to something (as an idea, proposition, text, melodic phrase, or mood) which a writer, composer, or artist proposes to develop (as in a poem), to elaborate upon (as in a movement of a symphony), or to illustrate (as in a mural or series of murals) or which can be detected in a completed work as the dominant object of his concern.
Theme does not necessarily suggest a clearer definition than subject or topic , but, in distinction from them, it invites comparison with the treatment and calls attention to the quality, the form, the design, or the execution of the completed work; thus, an overworked theme implies a lack of freshness in the thought or design; a compelling theme suggests force and enthusiasm in its treatment.
Motive and motif are restricted in reference to works of art to those in which design or pattern is the important element. In music they are interchangeable in this sense with theme , the leading phrase which is repeated with variations during the course of a composition or movement; in the decorative arts they apply to the figure which stands out as the salient and dominant feature of the design and is repeated at appropriate intervals.
Leitmotiv designates a specific melodic phrase that is associated with a particular person, mood, or situation (as in an opera) and that is repeated each time this person, mood, or situation reappears. The word has considerable extended use and is often applied to an insistent or recurrent idea that becomes the dominant theme of an author or of a work.