Rhetoric is the art of effective public speaking and writing. Rhetoric was first employed in ancient Greece, where rhetoricians used the power of persuasive speaking and writing to sway others toward their ways of thinking. The ancient art of rhetoric was later adopted by the Romans and continues to be utilized in public speaking and composition courses in modern education. The Rhetorical Triangle was originally introduced by Aristotle.

Rhetorical Triangle Origins

Aristotle introduced the Rhetorical Triangle in his work “Rhetoric.” According to Aristotle, the purpose of rhetoric is to persuade others through argument by appealing to the emotions of others to sway their thinking. Aristotle lists three types of rhetoric: political discourse, forensic or legal persuasion and epideictic or ceremonial speaking. Each type of rhetoric employs the three elements of the rhetorical triangle, also called the Aristotelian Triad: ethos, pathos and logos.

Ethos

Ethos refers to the character or presence of the speaker or writer who is trying to persuade. The author must have -- or seem to have -- a credible argument and appear to be a trustworthy individual. If the argument is a technical one or requires expert knowledge, the speaker must establish his position as an expert. If the individual is not credible or trustworthy, the audience will not attend to his argument or be persuaded by it. The speaker must also use the appropriate tone or voice for the situation if he is to be effective in his presentation.

Pathos

Pathos refers to the role of an audience in a rhetorical situation. The argument must appeal to the emotions or values of the audience if it is to be effective. The rhetoric must stimulate the imagination of the reader or listener. The speaker or author must develop a sense of empathy in the audience. However, the speaker must take care not to appear manipulative or she risks losing ethos, her credibility with the audience.

Logos

Logos refers to the logic of the argument itself. A rhetorical text must be structured in a clear, logical manner. If an argument is illogical and unclear, the audience will not be able to follow it. Regardless of how charismatic the speaker or author is, if his argument is difficult to understand, he is unlikely to persuade his listeners. A text that is logical and easily understood is far more likely to sway the audience. An illogical argument can affect the audience's perception of the speaker, decreasing his ethos, his credibility with them.