Rhetoric: art of persuasion.

Often taken to refer to flowery or bombastic prose, or to deceitful persuasion, ‘rhetoric’ is also the name of a serious academic discipline and an important subject matter. The discipline of rhetoric is the study of the norms of effective communication. Classically (starting with Aristotle), rhetoric referred to the art of effective speech-making to public bodies —the address to a jury, to a legislative assembly, or to a group of people at a celebratory ceremony. Contemporary rhetoric studies all manner of communication, both descriptively (what made Dr. Martin Luther King’s “I Have a Dream” speech or Lincoln’s “Gettysburg Address” so effective?) and prescriptively (what does a writer need to do in order to keep the attention, interest and receptivity of his or her readers?). In the latter sense, rhetoric and logic are not only compatible, but good rhetoric is needed to ensure that good logic gets a hearing.

Source: What is Good? What is Bad? The Value of All Values across Time, Place and Theories’ by John McMurtry, Philosophy and World Problems, Volume I-III, UNESCO in partnership with Encyclopedia of Life Support Systems: Oxford, 2004-11.