In other words, we seem to be witnessing a gap between poetic practice and rhetorical theorization. It appears, from the theoretical point of view, that straightforward, immediately comprehensible metaphors, preferably already codified, are to be preferred.
Geoffrey of Vinsauf (Poetria nova, 1705–1708) will affirm that there are three ways to develop one’s style: through the art whose rules one follows, through custom to which one conforms, and through the imitation of models. John of Salisbury (Metalogicon I, 24) tells us how Bernard of Chartres conducted his classes: he pointed out what was simple and in conformity with the rules, he demonstrated the grammatical figures, the rhetorical colors and the subtleties of argumentation and, to teach the splendor orationis (“splendor of discourse”), he demonstrated the marvels of translatio (in other words, metaphor) “ubi sermo ex causa probabili ad alienum traducitur significationem” (“whereby speech is transferred to some alien meaning for a most likely cause”). The student who did not observe his strictures was educated “flagellis et poenis.” (“with whipping and punishments”). But he did not punish plagiary, though he pointed it out—as if to say that theft was preferable to having an overbold metaphor betray the causa probabilis, or the affinities acceptable between metaphorizer and metaphorized.
Be that as it may, in the classical rules for distinguishing the lofty style, the mediocre and temperate, the vicious or extenuated, the bucolic or pastoral and humble, the georgic and mediocre, and the epic or sublime or grand styles—from the Rhetorica ad Herennium to the Schola Vindobonensia ad Horatii Artem poeticam (probably dating from the eleventh century) to the De ornamentis verborum of Marbode of Rennes, down to the artes poeticae of the twelfth and thirteenth centuries (Matthew of Vendôme, Geoffrey of Vinsauf, and John of Garland)—the examples of the words to be preferred are always canonicaclass="underline" lychnos is preferable to lucerna; in referring to Karolus, it belongs to the lofty style to say that he is “Ecclesiae clypeus et pacis columna” (“the shield of the Church and a column of peace”), but vicious to say he is “clava pacis” (“the cudgel of peace”); it is temperate or mediocre to say he is “Ecclesiae custos” (“the guardian of the Church”) and vicious that he is “militiae baculus” (“the staff of the military”); it is humble to say “In tergo clavem pastor portat, ferit inde—presbyterum, cum quo ludere sponsa solet” (“the shepherd carries a club on his shoulder, then he strikes the priest with it, who is wont to sport with his wife”), but it is vicious to say “Rusticus a tergo clavem trahit et ter tonse (or pertonso)—testiculos aufert, prandia laeta facit” (“the peasant takes the club from his back and tears off the priest’s testicles, of which he makes a good meal”). And even the metaphorical terms defining the styles are themselves defined by the tradition, “fluctuans et dissolutum, turgidum et inflatum, aridum et exsangue” (Matthew of Vendôme, Ars versificatoria I, 30).
What is most appreciated in metaphors is the color rhetoricus they bring with them, and hence their ornamental value, since for the theoreticians of medieval poetics the proper end of poetry is invariably grace and elegance: for Matthew of Vendôme (Ars III, 18) “fiunt autem tropi ad eloquii suavitatem” (“the tropes are made for the pleasantness of the discourse”).
A somewhat singular attempt to provide a logical-semantic rule for the generation of good metaphors is the one proposed by Geoffrey of Vinsauf, who in his Documentum de arte dictandi et versificandi (Faraclass="underline" 285–289) endeavors to establish codified procedures, based on the identity of properties between metaphorizer and metaphorized.10 Hence, it is established that the verb nasci (to be born) is properly used only of animals, but it has something in common with other actions, such as “to begin.” In which case, we can say “nascuntur flores” (in the sense that the flowers begin to be “incipiunt esse”), or “nascitur istud opus,” or “nata est malitia in diebus nostris” (“evil is born in our day”). And, by an analogous procedure, we can say “pubescit humus.” For Geoffrey, this artifice “est planissima via ad inveniendum translationes” (Faraclass="underline" 287).
Some historians (Dronke 1986: 14–16 and Bertini 2003: 35) have identified in Geoffrey a precise notion of the cognitive function of metaphor, in the sense in which it would be taken up by Dante in his Letter to Cangrande della Scala (Epistole XIII, 29), where he says of the things seen during his celestial journey that, since they cannot be expressed “sermone proprio” (“in everyday language”), they must be spoken of “per assumptionem metaphorismorum” (“by the employment of metaphors”). Nevertheless—setting aside Dante, to whom we will return—Geoffrey repeats that in constructing metaphors it would be wrong not to draw the properties from among those that are “expressissime et apparentissime similia” (“most expressly and apparently similar,” II, 3, 17–18). Obviously, milk and snow are white, and honey is sweet, but Geoffrey does not seem to advise identifying properties that are nonself-evident in order to create unexpected likenesses. Indeed (in II, 3) he denounces as “turgidus et inflatus” (“turgid and inflated’) that style “qui nimis duris et ampullosis utitur translationibus,” (“which has recourse to crude and bombastic metaphors”), such as saying “ego transivi per montes belli” (“I have crossed over the mountains of war”) instead of settling for “per difficultates belli” (“the hardships of war”).
And in fact the same author, in his Poetria nova (765 et seq.), suggests the use of prefabricated metaphors, so to speak. Instead of “aurum fulvum, lac nitidum, rosa praerubicunda, mel dulcifluum, flammae rutilae, corpus nivis album” (“tawny gold, limpid milk, a rose redder than red, smooth-flowing honey, ruddy flames, a body white as snow”) it is better to say “dentes nivei, labra flammea, gustus mellitus, vultus roseus, frons lactea, crinis aureus” (“snow-white teeth, lips of flame, a taste like honey, rosy cheeks, a milk-white brow, golden hair). It is acceptable to say that spring paints the earth with flowers, that fair weather soothes, that the winds are sleeping, that deep valleys lie, because, by transferring human actions to nonhuman things, man sees himself in nature, as in a mirror. But this is still the canonical procedure of the anthropomorphization of the inanimate. Furthermore, though Geoffrey may venture a rule which we have dubbed logical-semantic, in point of fact he does not suggest any criterion for the proper identification of the relevant properties.
3.2. References and Examples in Philosophical Thought
We might expect greater commitment on the part of the philosophers, who deal with the correct meaning of terms and the difference between univocal and equivocal signs. In her essay “Prata rident”, Rosier-Catach (1997) examines a canonical topos in medieval doctrinal thought: the metaphor of the smiling meadow (already present in Ad Herennium 4). It is striking how this same example occurs over and over again in very different authors, from Abelard to Theodoric of Chartres and William of Conches, down to Thomas Aquinas, eventually spilling over into the discussions of analogy or translatio in divinis, in other words, the use of metaphors to speak of God.