The Third Matter
Know that the beauty and perfection of speech, and the rhetorical garment with which it is clothed, lie in its manner of expression (uslûb). And its manner of expression consists of the form of the truths and the model of meanings obtained from the pieces of the allegorical metaphors (al-isti'ârât al-tamthîliyya). As though those pieces were an imaginary cinema, like the word 'fruit' points to its orchard, and the word 'combat' to the battlefield.
Moreover, allegorical comparisons (al-tamthîlât) are founded on the mystery of the relations between things, and their reflection in the order of the universe, and some things recalling others. For example, for the sons of the date-palm [the Arabs], the sight of the crescent moon in the constellation of the Pleaides calls to mind a bunch of grapes [a cluster of dates] hanging from a curved whitened stalk. As the Revelation says: "... till it returns like an old date-stalk, withered and curved."(36:39)
The usefulness of comparisons (uslûb al-tamthîl), as shown in the verses given previously, is that by means of them the speaker brings to light [raises to the surface] deep roots and unites scattered meanings. When he hands one side to his listener, it is possible for the listener to draw the remainder towards himself; since they have been brought together, he can transfer to them mentally. Since he sees some, though they may be in the dark, he can progress step by step towards all of them.
For instance, a jeweller defines eloquent speech as "an idea that bores [a pearl like a drill]." While a taverner would say that it is "what is cooked in the cauldrons of knowledge." And a camel driver would say of eloquent speech, that it is "what you take by the halter and cause to recline in the hollow of the meaning." Observing the art in these definitions, someone hearing them would comprehend all they intended.
The wisdom in the formation of the literary device (uslûb) [of comparisons] is that voluntarily the speaker hails and arouses the meanings reposing in the nooks and crannies of his heart, stark and bare. They emerge and enter the imagination, and don the garments of whatever form they find, that are found there by reason of the speaker's art or occupation or familiarity or need. Or at least they tie a kerchief of his art around their heads, or are tinted with its hues. The exordia you find in the prefaces of books form the best examples of this matter.