From a rhetorical point of view, metaphor is valued as a cryptic analogy, the clarification of which is entrusted to the audience. The key difference between metaphor and analogy is that, while analogy keeps the two domains it relates separate and distinct, metaphor tends to conflate them.
According to Aristotle, metaphor is the most efficient persuasive instrument of ordinary discourse. From the perspective of an anti-rhetorical theory of argumentation, metaphor is abundantly misleading. But metaphor is also a powerful cognitive tool for building representations, and better understanding complex situations. Metaphor applies the language of a model, i.e. the Resource domain (the metaphorical term) to an actual situation, the Problematic domain to which belongs the (sometimes missing) metaphorized term, S. Structural Analogy.
1. Metaphor put on trial
If metaphor is defined as a figure, and figures are defined as ornaments, then metaphor is misleading in all its dimensions, S. Fallacy; Ornamental fallacy. The metaphorical statement is false: “The voter is a calf” said Charles de Gaulle; but the voter (proper term) is not a calf (metaphorical term) the voter is a human being. Metaphor systematically commits a category mistake. One can also accuse metaphor of creating ambiguity, because it introduces a parasitic level of signification, the figurative meaning, running parallel to the proper, standard meaning.
Metaphor pops up, creating a surprise and introducing an emotion (ad passiones fallacy); it entertains the audience (ad populum fallacy), thus sacrificing docere to placere. It turns the reasonable arguer into an actor (ad ludicrum fallacy). Metaphor is therefore the discursive distractor par excellence, putting the audience on a false trail, and confusing the honest literal individual in his or her pursuit for truth. S. Relevance; Red Herring; Resumption of discourse.
Therefore, metaphor is, and should be, banished from serious argumentative discourse, as it is from scientific language; it can be helpful only when re-formulated as a comparison (Ortony 1979, p. 191). Nevertheless, it should be pointed out that metaphor is active and welcome to stimulate creativity and facilitate science transmission and popularization.
2. Metaphor, the ultimate weapon of persuasion?
Persuasion, pistis, is produced in three ways “(1) by working on the emotions of the judges themselves, (2) by giving them the right impression of the speaker’s character, or (3) by proving the truth of the statements made” (Aristotle, Rhet., 1403b10; RR p. 397), in the latter case, persuasion emerging “from the facts themselves” (ibid).
Ideally, the issue should be discussed on the basis of facts and proofs: “we ought in fairness to fight our case with no help beyond the bare facts: nothing, therefore should matter except the proof of those facts” (ibid 1404a1; RR p. 399). But normal people are not perfect, and “owing to the defects of our hearers”, and of our “political institutions”, “the arts of language cannot help having a small but real importance” in public discourse and education — but not in geometry: “nobody uses fine language when teaching geometry” (1404a1-10, RR. p. 399).
So, refined language is the most effective tool of persuasion. Persuasion by emotion (pathos) and image (ethos) is produced, orally, by the “oratorical action”; in writing, by the stylistic arrangement of facts, “because speeches of the written or literary kind owe more to their diction than to their thought” (1404a15; p. 401). Metaphor is the supreme tool of written discourse “both in poetry and in prose”; it “gives style clearness, charm and distinction as nothing else can” (1405a1-10; RR, p. 405). The conclusion is clear: metaphor is the ultimate weapon of persuasion, defined as the art of “[hiding one’s] purpose successfully” (1404b20; RR, p. 403), and charming the audience, S. Logos, Ethos, Pathos.
Contemporary approaches to metaphor unanimously consider that metaphor derives this power from the intrinsic element of surprise, resulting from the perception of an anomaly in the discourse, a rupture, an inconsistency, an incongruity, a contradiction of logic, in short, a discursive coup, to the audience’s delight. Pleasure cannot be rebutted, and metaphor is thus considered to be quasi inaccessible to refutation — in reality, it is: cf. infra, §4
3. Metaphor and interpretative cooperation
Using a metaphor, the speaker openly seeks the interpretative cooperation of the audience; creating cooperation, metaphor strengthens the importance of prior agreements. Note that the same functional explanation is given for the derivation of enthymemes from underlying syllogisms. In both cases, the argumentative (i.e. effective, persuasive) function of the enthymematic or metaphoric condensation is the activation of the partner, S. Enthymeme §5.
This analysis assumes that the non-argumentative metaphorical language, or the non-elliptic syllogism would be transparent, or less complex than the metaphorical language, and that their direct interpretation would not require the same degree of cooperation from the audience, which is not self-evident.
4. Metaphor as analogy
Metaphor finds smart solutions to the riddle of metaphor:
Metaphor is the dreamwork of language and, like all dreamwork, its interpretation reflects as much on the interpreter as on the originator. The interpretation of dreams requires collaboration between a dreamer and a waker, even if they be the same person; and the act of interpretation is itself a work of the imagination. So too, understanding a metaphor is as much a creative endeavor as making a metaphor, and as little guided by rules.
(Davidson 1978, p. 29)
In The Interpretation of Dreams (1900) Freud defines dream-work as the process by which the latent content of a dream is covered by its manifest content, by displacement, distortion, condensation and symbolism. The metaphor “metaphor / dream work” is difficult to reject, even if it commits the fallacy of trying to go ad obscurum per obscurius, that is, it attempts to illuminate the dark (metaphor) by the darker (the dream work).
The metaphor is a model, (Black 1962), and an imperialist model, urging one to identify the metaphorized reality within the metaphorical world:
L1 — we should do something with the economy…
L2 — with the “economy-casino” you mean\
L1 — oh yes, all these addicted traders should be banned from the market!
Reconstructed analogy “as addicted players are banned from casinos”
Saying that “the voter is a calf” is to mean that “the voter is hesitant, weak and can be manipulated like a calf”, calves being here the stereotypical animal combining these characteristics. The metaphor opens new perspectives, and legitimates a new set of inferences about voters: if they are categorized as calves, one can make them adopt behaviors directly contrary to their interests, e.g. to lead them to a more or less metaphorical slaughterhouse.
Metaphor draws its argumentative strength from an analogy pushed to identification. Structural analogy explicitly brings together two domains, respecting their specificities; the domains are confronted, not assimilated. Metaphor renders the comparison implicit, negates the metaphorized domain, assimilated to the metaphorical one. This is why the reconstruction of the analogy underlying the metaphorical expression betrays metaphor: it splits apart what metaphor has joined together. Peter is a lion: the language referring to lions is substituted for the language referring to humans; we are not far from the hyper-unitary coherent Renaissance world where everything is mirrored in everything,, S. Analogical thinking.
5. Jumping from analogy to identity?
Analogy can be defined as a partial identity. The question of possible profound identity, underlying immediately discernible differences plays an essential role here:
Snowdrifts are like corrugated iron.
Snowdrifts are like dunes.
The syntactic structures of these two statements are identical, both propose the image of “waves” to the interlocutor, and a key common semantic feature, /waving/. But the second comparison is deeper; it opens the way to a theory. It introduces an analogy of proportion:
snow : snowdrift :: sand : dune
It suggests that the analogy can be explained by the action of wind on, respectively, the snow particles and sand grains. It puts the hearer on the way to the construction of a physical-mathematical model covering the two phenomena (with due respect paid to the differences between the two kinds of particles, grains of sand and snowflakes, and their respective laws of agglomeration). From two apparently distinct phenomena (one can know what a dune is without knowing what a snowdrift is, and vice-versa), we end up with the problem of a unifying abstract representation: can the same physical model account for the two phenomena?
Establishing an analogy may be considered to be the first step toward the affirmation of an in-depth identity. Such a shift, from explanatory analogy to identity is at the center of a class of arguments about analogy, which fit perfectly into the framework of a vision of metaphor, not only as a model but also as the genuine essence of the metaphorized phenomenon.
6. Mole rats “societies”, human society: metaphor or identity?
The following texts and information are taken from S. Braude & E. Lacey, “A revolutionary monarchy: the society of mole rats”. Mole rats are mammals, precisely hairless rats, living in “groups” or “communities” (the difference is relevant); they exhibit behaviors evoking those observed among social insects, like ants or bees. But this behavior has never been observed in mammals. Hairless mole rats are thus the first mammals with this kind of “social behavior”.
But, when speaking of “social behavior” or “community”, do we use a simple analogical-metaphorical lexicon, a pedagogical or explanatory metaphor? Or are we engaged in a process of describing these newly identified animal behaviors in terms of the existing structures of human societies? Do we suggests, as in the case of the dunes and snowdrifts, that both phenomena may well have the same foundations, biological in this case? Does the organization of human societies obey the same biological laws as apply to mole rat “societies”? Are we on the way towards a socio-biological theory of human societies? Have we moved surreptitiously from metaphorical language to identification?
This is a strategy of “slippery metaphor”. This strategy is so successful, that it reverses the relationship Target / Resource. Being closer to nature, mole rats, formerly the Target, now become a model for the study of human society, formerly the Resource.
In order to reject this assimilation, the opponent lists the terms coming from the field Resource, the human social lexicon:
The phrase “division of labor” is used four times; the word “task” also appears four times; the term “responsible” also appears four times, and “they take care of” once; the terms “cooperation” and “subordinate” are used once each. The expression “sexual status” is used three times to refer to the reproductive state of the animals. (G. Lepape, [Investigation], 1992)
In their reply to this criticism, the authors of the article set limits to the identification of the two areas:
G. Lepape also contends that our language introduces unfair comparisons which attribute common behavioral traits to mole rats and social insects. This assertion surprises us, especially when he writes, “the similarities [between hairless mole rats and social insects] are treated as true homologies”. Our article is clear on that point: we believe that the behavior of hairless mole rats and eusocial insects have striking similarities. However, we do not see how the language used to describe these similarities can suggest that a common origin of these animals would constitute the evolutionary basis of these similarities.
Braude & Lacey, id..
The danger here is that we might be tempted to forget that we are dealing with analogy, which is “never more compelling than when it is abolished and ceases to be perceived as an analogy. Becoming invisible, it merges with the order of things.” (Gadoffre 1980, p. 6)
7. Against metaphors
Politicians [are] catering to a public that doesn’t understand the rationale for deficit spending, that tends to think of the government budget via analogies with family finances.
When John Boehner, the Republican leader, opposed US stimulus plans on the grounds that “American families are tightening their belt, but they don’t see the government tightening its belt”, economists cringed at the stupidity. But within a few months the very same line was showing up in Barack Obama’s speeches […]. Similarly, the Labour party […] (The Guardian 04-29-2015)
The “stupidity” is that of inference “families are tightening their belts, SO the state must tighten its belt”. We can reconstruct the warranting principle of this argument as a metaphor:
A state, a nation, a country is a family.
One could also think of a kind of composition:
The state is made up of families, families are tightening their belts, the state must tighten its belt.
However, the metaphor “state, family” has deep roots; it is based on the etymology of the word economy, from the Greek oikonomia, “home management”; it is found in the praise of the leader as “father of the nation”, “founding father”, etc.
Krugman considers that politicians are “catering” (“providing what the public wants, desires or what amuses them”; after d.c, cater) to a public “that doesn’t understand”; so politicians must use metaphors, and metaphors, at least this metaphor – is stupid — this is indeed exactly what Aristotle said, cf. supra.
Happy metaphors do serve to charm the audience, but the fact that there are also unhappy metaphors must be fully acknowledged. Where they are used, the interlocutors are not only not “charmed”, showing no pleasure, but they also “cringe at the stupidity”, that is, “show on their face and bodies their feeling of disgust and embarrassment” (after MW, Cringe). This is exactly how metaphor can be rebutted as metaphors.
Then, in a second step, the accounts can be settled with the substantial contents, that is the de-metaphorized claim “in times of economic crisis, the state must turn to austerity”. Krugman conducts this substantive rebuttal in the semi-technical language of economics, combining a priori refutation (theoretically ill-grounded), falsification (forecasts contradicted by facts) and pragmatic refutation (policies inspired by this theory have failed). But a second metaphor remains; if words such as restriction and austerity, have a clearly negative orientation, the expression “to tighten one’s belt”, associated with successful diet, weight loss, slimness, has strong visual, irrefutable positive connotations, inaccessible to refutation.
 Braude, S. & Lacey E. (1989). Une monarchie révolutionnaire: la société des rats-taupes. La Recherche [Investigation], a journal of general scientific information] July-August 1989. Comments from G. Le Pape, and reply of the authors in the same journal, Oct. 1992.
 “Living in a cooperative group in which usually one female and several males are reproductively active and the nonbreeding individuals care for the young or protect and provide for the group eusocial termites, ants, and naked mole rats” (MW, Eusocial)
 www.theguardian.com/business/ng-interactive/2015/apr/29/the-austerity-delusion (15-08-16)