Aristotle defined the basic oratory forms, types of speech or writing that tell a story using ethos, pathos and logos. Pathos defines an appeal to emotion while logos uses logic. Ethos incorporates a number of concepts, including the authority created during the oratory and the reputation the speaker or author before the presentation. Speakers and authors with ethos have built-in credibility and authority, and they enhance the quality during the presentation. Scholars of modern political oratory add discursive and rhetorical political presentations to Aristotle's three classic forms.

Deliberative Oratory

The deliberative form, one of the basic types of oratory identified by Aristotle, defines classic political oratory. Deliberative oratory presents logic and argument, and it encourages listeners to take actions recommended by the speaker or author. Politicians typically use this type of oratory for speeches given to Congress or legislative bodies.

Forensic Form

The forensic oratory form as defined by Aristotle organizes arguments to make a charge or answer a legal challenge. Modern politicians use the forensic form, sometimes called the judicial form by modern scholars, to attempt to explain away legal charges. Then-Vice President Richard Nixon's "Checkers Speech" in 1952 denied political charges of campaign influence using a modified forensic form, and President Clinton used a simple format of this oratory type when answering impeachment challenges. Traditional forensic oratory typically relies on logic to make an argument, but Clinton and Nixon also used emotional appeals.

Epideictic Oratorical Form

The epideictic, the last of Aristotle's classic oratorical forms, focuses on ceremonial oratory. Speakers and authors use this presentation to celebrate a person for a funeral oration or in an obituary. The subject of the epideictic doesn't need to be dead, however; the orator also can assign blame for a problem or condition, according to the "Silva Rhetoricae." Oratories celebrating a retiree, graduate and new appointees also come under this oratory heading.

Discursive Type

The discursive, a modern political oratory type, makes up one of the core forms of oratorical study since the 1960s. This loose form uses an open organizational style that is frequently difficult to follow. The speaker or writer typically includes a main idea with a random flow of examples, illustrations, narratives and facts. Discursive oratory makes heavy use of either ethos or pathos and less emphasis on logic, support or development of major arguments.

Rhetorical Oratory

The rhetorical approach is a more modern interpretation that incorporates one or several of Aristotle's three classic forms, but the type also carefully creates a presentation style that focuses on the effectiveness of the presentation from the audience viewpoint. Aristotle believed that an equal balance between ethos, pathos and logos created the ideal message, but modern orators also evaluate the audience for the message to determine the effectiveness of the presentation. Ethos development and presenting a face to the audience that the speaker has the authority, ability and expertise encourages listeners to trust the orator.