Ancient rhetoric

Rhetoric, the art of persuasion through the development of arguments, has its origins in Mesopotamia. Some of the earliest examples of rhetoric can be found in the Akkadian writings of the princess and priestess Enheduanna (c. 2285–2250 BCE), while later examples can be found in the Neo-Assyrian Empire during the time of Sennacherib (704–681 BCE). In ancient Egypt, rhetoric had existed since at least the Middle Kingdom period (c. 2080–1640 BCE). The Egyptians held eloquent speaking in high esteem, and it was a skill that had a very high value in their society. The "Egyptian rules of rhetoric" also clearly specified that knowing when not to speak is essential. Their approach to rhetoric was thus a "balance between eloquence and wise silence". Their rules of speech also strongly emphasized "adherence to social behaviors that support a conservative status quo" and they held that "skilled speech should support, not question, society."

In the 4th century BCE, rhetoric was defined by Aristotle as "the faculty of observing in any given case the available means of persuasion" and since mastery of the art was necessary for victory in a case at law, or for passage of proposals in the assembly, or for fame as a speaker in civic ceremonies. He called it "a combination of the science of logic and of the ethical branch of politics" and divided it into three categories, logos, pathos, and ethos. 

In the political rise of the Roman Republic, Instruction in rhetoric developed into a full curriculum, including instruction in grammar (study of the poets), preliminary exercises (progymnasmata), and preparation of public speeches (declamation) in both forensic and deliberative genres. The Latin style of rhetoric involved a strong emphasis on a broad education in all areas of humanistic study in the liberal arts, including philosophy. Other areas of study included the use of wit and humor, the appeal to the listener's emotions, and the use of digressions. 

Quintilian (35-100 CE) organized rhetorical study into  five canons:

Inventio (invention) is the process that leads to the development and refinement of an argument.

Once arguments are developed, dispositio (disposition, or arrangement) is used to determine how it should be organized for greatest effect, usually beginning with the exordium.

Once the speech content is known and the structure is determined, the next steps involve elocutio (style) and pronuntiatio (presentation).

Memoria (memory) comes to play as the speaker recalls each of these elements during the speech.

Actio (delivery) is the final step as the speech is presented in a gracious and pleasing way to the audience, often referred to as the Grand Style. A common feature of rhetoric in the grand style is the use of a repeated pattern, often emphasizing a word or phrase at the beginning or end of a series of clauses.

In every cry of every man,

In every infant's cry of fear,

In every voice, in every ban,

The mind-forged manacles I hear:

—William Blake

Or

Where affections bear rule, their reason is subdued, honesty is subdued, good will is subdued, and all things else that withstand evil for ever are subdued. - Thomas Wilson.

Image: Bronze statue of a man mid-2nd -1st century BCE, Greek, at the Metropolitan Museum of Art. Honorific statues like this one were typically portraits of prominent individuals awarded by the city-state or ruler in gratitude for significant benefactions. They were the highest honor that a city could offer. This impressive figure stands in contrapposto. His right hand stretches out from the folds of his himation (cloak), with open palm and fingers curled upward in a gesture of oration. His left arm lies close to his body. The himation is kept in place in part by the tasseled weight thrown over his left shoulder, which hangs at his calf, and the indication of his musculature and anatomy continues underneath his garment. The several horizontal bands that decorate the fabric,which may have been painted or gilded, comprise a rare detail.