1. Parameters of political debate

Political deliberation is a problem-solving activity. The following interrogative framework groups the most general questions that must be answered before deciding whether or not to adopt or reject a measure of general interest

Is this measure legal? Just? Honorable? Timely? Useful? Necessary? Safe? Possible? Easy? Pleasant? What are the foreseeable consequences? (After Nadeau 1958, p. 62).

This framework functions on different modes.
— On the interrogative-deliberative mode, it guides a practical decision process:

If you are considering such a measure, look at whether it is just, necessary, feasi- ble, glorious, profitable, and whether it will have positive consequences.

In this case, the set of questions is used as a heuristic. One can take up a re- sponsible political position on a given issue by examining each point and providing a well-argued answer to each question.

— On the prescriptive-justificatory mode, it helps to develop a global, positive or negative persuasive argumentative script about an issue:

If you want to support (or to attack) such measure, show that it is (or it is not) just, necessary, etc.

— On the analytical-critical mode, it serves to test the completeness of an argumentation

You argue that this measure is just, necessary, glorious; but you say nothing about its consequences and the practical modalities of its realization.

In practice, this simple, robust and effective topic applies to any practical public or private decision.

2. Arguments/fallacies of parliamentary debate:
Bentham’s collection

In The Book of Fallacies [1824], Bentham focuses exclusively on fallacious arguments in parliamentary debates. This collection is strongly oriented towards the refutation of conservative discourse, S. Collection (II). In the same spirit, Hirschman has analyzed The Rhetoric of Reaction (1991).
In politics, sophists are accused of indulging in obstructive or manipulative maneuvers, producing bad arguments in bad faith, rejecting legitimate discussion, and serving dishonest or anti-popular purposes.

Bentham distinguishes four main categories of fallacies: fallacies of authority, of danger; of delay, of confusion.

(i) Fallacies of authority

S. Modesty; Threat; Politeness; Personal Attack

— “The wisdom of our ancestors, or Chinese argument; ad verecundiam.” (p.69)

—“Irrevocable law; ad superstitionem”.

— “Fallacy of vows or promissory oaths; ad superstitionem”

“The object of this fallacy is the same as in the preceding; but to the absurdity involved in the notion of tying up the hands of generations yet to come is added, in this case, that which consists in the use sought to be made of supernatural power.” (p. 104)

—“No-precedent argument; ad verecundiam”

“The proposition is of a novel and unprecedented complexion: the present is surely the first time that any such thing was ever heard of in this house.” (p. 115)

— “Self-assumed authority; ad ignorantiam; ad verecundiam” (p. 116)

— “Self-trumpeter’s fallacy”

“There are certain men in office who (…) arrogate to themselves a degree of probity, which is to exclude all imputations and all in- quiry.” (p. 120)

— “Laudatory personalities; ad amicitiam”

“The object of laudatory personalities is to effect the rejection of a measure on account of the alleged good character of those who oppose it.” (p. 123)

(ii) Fallacies of danger, appealing to fear (ad metum) or hate (ad odium)
to repress discussion

S. Emotion; Threat.

— “Vituperative personalities; ad odium” (p. 128).

Attacking the person: “Imputation of bad design; of bad character; of bad motive; of inconsistency; of suspicious connections; imputation founded on identity of denomination.” (p. 127-128)

— “Hobgoblin argument or: No innovation!; ad metum” (p. 145)

Innovation leads to anarchy.

— “Fallacy of distrust

What’s at the bottom?” (p. 154)

— “Official malefactor’s screen (ad metum)

Attack us, you attack Government.” (p. 158)

— “Accusation-scarer’s device.” (p. 184)

(iii) Fallacies of delay

These fallacies play for time, with the intention “to postpone discussion, with a view of eluding it”. Some are based on stupidity and laziness (Lat. socordia):

— “The quietist, or ‘No complaint’ (ad quietem)

Nobody complains, therefore nobody suffers” (p.190); so, no need to change.

— “False consolation (ad quietem)”

“Look at the people there, and there: think how much better off you are than they are.” (p. 194)

— “Procrastinator’s argument (ad socordiam)”

Wait a little, this is not the time!” (p. 198)

— “Snail’s pace argument (ad socordiam])”:

“One thing at a time! Not too fast! Slow and sure!” (p. 201)

— “Artful diversion (ad verecundiam)”

“Why that? (meaning the measure already proposed) — Why not this? — or this?” (p. 209)

(iv) Fallacies of confusion

“[their] object is to perplex, when discussion can no longer be avoided” (p. 213), S. Personal attack; Ambiguity; Ad populum; for Ad judicium, S. Matter

— “Question-begging appellatives (ad judicium)”

The use of “eulogistic terms” and “dyslogistic or vituperative terms.” (p. 214)

— “Impostor terms (ad judicium)”

“For instance, persecutors in matters of religion have no such word as persecution in their vocabulary; zeal is the word by which they characterize all their actions.” (p. 221)

— “Vague generalities (ad judicium)”

A fallacy “resorted to by those who, in prefer- ence to the most particular and determinate terms and expression (…) employ others more general and indeterminate.” (p. 230)

— “Allegorical idols (ad imaginationem)”

“substituting for men’s official denomination the name of some fictitious entity, to whom (…) the attribute of excellence has been attached. Example: Government, for members of the governing body.” (p. 258)

— “Sweeping classifications (ad judicium)”

“ascribing to an individual (…) any prop- erties of another, only because the object in question is ranked in the class with that other” (p. 265) “Example 1: Kings; Crimes of Kings (…) criminals ought to be punished; kings are criminals, and Louis is a king: therefore Louis ought to be punished)” (p. 266)

— “Sham distinctions (ad judicium)”

“Declare your approbation of the good by its eulogistic name, and thus reserve to yourself the advantage of opposing it without reproach by its dyslogistic name (…) Example 1: Liberty and licen- tiousness of the press” (p. 271)

— “Popular corruption (ad superbiam)”

“The source of corruption is in the minds of the people; so rank and extensively seated is that corruption that no political reform can ever have any effect in removing it: This was an argument brought forward against parliamentary reform.” (p. 279)

— “Anti-rational fallacies (ad verecundiam)” — “When reason is found or supposed to be in opposition to a man’s interest, his study will naturally be to render the faculty itself and whatsoever issues from it an object of hatred and contempt” (p. 295)

— “Paradoxical assertions (ad judicium)”

“When of any measure, practice or principle the utility is too far above dispute to be capable of being impeached by rea- soning, a rhetorician (…) in a sort of fit of desperation (…) he has assailed it with some vehement note of reprobation or strain of invective” (p. 314). “Ex- ample: Good method, a bad thing.” (p. 316)

— “Non causa pro causa (ad judicium)”

“When in a system which has good points in it you have a set of abuses (…) to defend; (…) take the abuse you have to de- fend (…) and to them ascribe the credit of having given birth to the good ef- fects” (p. 328)

— “Partiality-preacher’s argument (ad judicium)

A discussion of the maxim: “From the abuse, argue not against use.” (p. 339)

— “The end justifies the means (ad judicium)” — A discussion of the maxim (p. 341).

— “Opposer-general’s justification (ad invidiam)”

“it is not right for a man to argue against his own opinion. (…) If a member of the House of Commons, and in opposition, a measure which to him seems a proper one is brought on the carpet on the ministerial side, it is not right that he should declare it to be, in his opinion, pernicious, and use his endeavours to have it thought so, and treated as such by the House” (p. 344), and reciprocally.

— “Rejection instead of amendment (ad judicium)”

“this fallacy consists in urging in the character of a bar, or conclusive objection against the proposed measure, some consideration, which, if presented in the character of an amendment, might have more or less claim to notice.” (p. 349)

Bentham does not express the fallacies under any “logical form”, but presents them in the form of statements that are condensed argumentations, sometimes in the form of a slogan. The topoi are getting closer to the discursive clichés.
Bentham condemns these maneuvers as prima facie fallacies, and discusses them further under the corresponding heading.

The verbal aspects of interpersonal relationships are regulated by a set of principles defining linguistic politeness:

Politeness refers to all aspects of the discourse, 1. which are governed by rules, 2. which intervene in the interpersonal relationship, 3. and which have the function of preserving an harmonious relationship (at worst: neutralizing potential conflicts and, at best, ensuring that each participant is as open to the other as possible). (Kerbrat-Orecchioni 1992, p. 159; 163)

Ordinary conversation is governed by the principle of preference for agreement. The interactionist theory of politeness (Brown and Levinson, 1978) defines the individual by his or her faces and territories. Polite intervention respects rules of positive politeness and rules of negative politeness, both towards oneself, and to- wards the interlocutor. In argumentative situations, this preference for agree- ment is transformed into a preference for disagreement (Bilmes 1991). Differences are maximized, which has consequences for all the components of the system of linguistic politeness. The case of the ad verecundiam argument is a typical illus- tration of this transformation, S. Modesty.

1. Politeness oriented towards the addressee

Negative politeness recommends the avoidance of face-threatening acts whilst positive politeness recommends that positive acts be enacted in relation to the territories and the face of the interlocutor (Kerbrat-Orecchioni 1992, p. 184).
The argumentative situation reverses these principles. The rules of positive politeness are not applied, whilst those of negative politeness are inverted. For example, the rule “avoid encroachments on the interlocutor’s private territo- ries” (id., p. 184) corresponds to a principle of non-aggression, “do not violate the territory of the other”. In an argumentative situation, there is necessarily a form of aggression and territorial conflict, with encroachments and counter- encroachments being made.

Another general rule of politeness recommends that parties “[refrain] from making disparaging remarks, too sharp criticisms, too radical refutations, too violent reproaches” (ibid.) – to their conversational partner; whereas, in a situation of argumentation, radical refutation is sought rather than avoided and negative challenging of the opponent is a standard strategy. Praise for the interloc- utor turns out to be an attack against the position he defends in the current interaction, S. Counter-argumentation.
The ban on personal attacks is a matter of politeness aimed at protecting the interlocutor, for aspects of his person that are not at stake in the debate.

2. Politeness oriented towards oneself

The principles of defense the speaker’s territory recommend that you “protect your territory as much as you can (resist over-invasive incursions, do not let yourself be dragged through the mud, do not allow your image to be unfairly degraded, respond to criticism, attacks and insults)” (ibid., p. 182-183). In argu- mentative situations, participants vigorously apply these protecting principles. In non-argumentative situations, the speaker territories must be protected, yet not unduly extended and praised, “our societies severely judge self-satisfaction and pro domo advocacy”, except in “exceptional circumstances” (ibid.). These exceptional circumstances are precisely those of argumentative situations, where speakers do not hesitate to praise their persons as well as their territories, that is, their point of views and arguments. The principles of moderation and self-valorization are thus put on hold. In non-argumentative interactions, “if you have to praise yourself, at least let it be in the attenuated mode of the un- derstatement” (id., 184); you can even “slightly damage your own territory, and practice light self-criticism” (id., 154). This principle requires that one be prepared to compromise and concede, all things that the arguing speaker can choose to do or not do, without being impolite.

The conclusion is that argumentative situations locally suspend the application of the rules of politeness in relation to the objects and persons involved in the discussion. This can even be seen as a fundamental characteristic, a defining criteria of such situations. The protagonists use a kind of “anti-system of politeness”, mirroring the system of politeness. Speaking of “a system of impo- liteness” however, would imply that all these interventions are felt to be impolite, which is not the case, notwithstanding the fact that, in such situations, the partners can engage in polemics about the “tone” of their interventions.

The redefinition of the system of politeness applies strictly to the aspects of the person, face and territories, which are engaged in the argumentative conflict. Outside these areas, politeness rules still apply. It is thus possible for an arguer to praise his or her personality and possessions and attack the standing or val- ues of those of his or her opponent in an argumentative interaction where his or her behavior will, independently, be polite or impolite.

1. Persuasion as the essence of rhetoric

Since Isocrates and Aristotle, argumentative rhetorical speech is commonly defined by its function, that being persuasion:

Rhetoric may be defined as the faculty of observing in any given case the available means of persuasion. (Rhet, I, 2, 1355b26, RR, p. 105).

According to Crassus as staged by Cicero, persuasion is the “first duty” of the orator (Cicero, De Or., I, XXXI; p. 40). Perelman & Olbrechts-Tyteca, focus their definition of argumentation on how “to induce or to increase the mind’s adherence to the theses presented for its assent” ([1958]/1969, p. 4; italics in the original) before elaborating on the notion of “adherence of minds” by means of an opposition between persuading and convincing speech, S. Assent; Persuading and convincing.

According to these standard definitions, argumentative rhetoric is fundamentally concerned with the discourse structured by the illocutionary (overtly expressed in the discourse) intention of persuading, that is to communicate, explain, legitimate, and make the listeners share the speaker’s point of view and the words that express it. Persuasion, as a perlocutory state obtained through discourse, results from the realization of these intentions.

The rhetorical tradition binds the discourse of persuasion to the production of a plausible representation in the audience’s minds. This rhetorical representation of reality is considered to be antagonistic towards truth by essentialist philosophers such as Plato, S. Probable.

2. A rhetoric without persuasion: the ars bene dicendi

Chapter 15 of Book II of Quintilian’s Institutes of Oratory is devoted to challenging the definition of rhetoric in relation to persuasion, “the most common definition therefore is that [rhetoric] is the power of persuading” (IO, II, 15, 3), this definition being attributed to Isocrates. Quintilian rejects all the definitions linking rhetoric to persuasion:
— As the power to persuade:

But money, likewise, has the power of persuasion, as do interest, and the authority and dignity of a speaker, and even his very look, unaccompanied by language, when either the remembrance of the services of any individual, or a pitiable appearance, or beauty of person, draws forth an opinion. (Id., 6)

— Or as an instrument of persuasion, even with the restriction “power of persuading by speaking”:

Not only the orator, but also others, such as harlots, flatterers, and seducers, persuade or lead to that which they wish, by speaking. (Ibid.)

Finally, Quintilian takes up the definition of rhetoric attributed to the Stoics and Chrysippus, “rhetoricen esse bene dicendi scientiam” (id., p. 841), that is to say, “the art to speak well and say the Good”:

The definition that [rhetoric] is the science of speaking well […] embraces all the virtues of [rhetoric] at once and includes also the character of the true orator, as he cannot speak well unless he be a good man. (Id., 34)

Its purpose is, “to think and speak rightly” (id., 36).

The rhetoric of persuasive communication and the rhetoric focusing on the quality of expression have been opposed as primary vs. secondary rhetoric (Kennedy 1999), or extrinsic vs. intrinsic rhetoric (Kienpointner 2003). We can also speak of an introverted rhetoric, focusing on the quality of an expression based on intellectual rigor and depth of feeling. Extroverted, communicative rhetoric strives to be eloquent, while introverted rhetoric requires an alternative concept of style.

Note that this distinction does not correspond to the distinction forwarded in the 1960s, between a restricted rhetoric opposed to a general rhetoric. Likewise, it has nothing to do with the distinction between rhetoric of arguments and rhetoric of figures. S. Rhetoric.

Introverted rhetoric is a rhetoric whose communicative and interactional dimensions, hence persuasiveness, are weakened, but which nevertheless remains an argumentative rhetoric. La Bruyère expresses as follows the concept of such a rhetoric having abdicated eloquence and persuasion:

We must only endeavor to think and speak justly ourselves, without aiming to bring others over to our Taste and Sentiments; that would be too great an enterprise. (La Bruyère, [Of Works of Genius], [1688])2

3. From persuasion to action

In an essential but often neglected complement to the basic definition of argumentation, the Treatise on Argumentation extends the scope of persuasion through argumentation to action. Argumentation would actually produce the “disposition to action”:

The goal of argumentation, as we have said before, is to create or increase the adherence of minds to the theses presented for their assent. An efficacious argument is one which succeeds in increasing this intensity of adherence among those who hear it in such a way as to set in motion the intended action (a positive action or an abstention from action) or at least in creating in the hearers a willingness to act which will appear at the right moment. (Perelman, Olbrechts-Tyteca, [1958], p. 45)

This vision is restated a little later:

Argumentation alone […] allows us to understand our decisions. (Id, p. 37)

The end point of the argumentative process, then, is not persuasion seen as a mere mental state, an “adherence of the mind”. The ultimate criterion of complete persuasion is an action accomplished in the sense suggested by discourse, and emotion plays an essential role where this is acted out. Adherence beyond a certain degree would trigger action. This is a crucial point where argument, emotions, and values are combined in order to give a response to the philosophical problem of action.

4. Persuasion, identification, self-persuasion?

Burke stressed that persuasion presupposes identification:

When you are with Athenians, it is easy to praise Athenians, but not when you are with the Lacedaemonians.
Here is perhaps the simplest case of persuasion. You persuade a man only insofar as you can talk his language by speech, gesture, tonality, order, image, attitude, idea, identifying your ways with his. (1950, p. 55).

According to the rhetorical doxa, the preliminary to a successful persuasive performance is based on agreements between the speaker and the audience S. Conditions of discussion. This negotiation of agreements could take place through a preliminary argumentative dialogue, running the risk of an infinite regression. So the orator resolves not to explicitly agree with his audience, but to adapt to it. For this reason, he or she makes a preliminary inquiry about the audience, in order to be able to correctly adapt to, or mimic, the audience. This is precisely what the theory of the ethos of audiences foresees, S. Ethos, §5: through ethotic suggestion, the speaker presents himself or herself as “one of you, the people”. Secondly, by logical proofs, the speaker gives prominence to the values and judgments accepted by his or her audience (he or she argues ex concessis). Thirdly, appealing to pathemic communion with the audience, empathy is shown.

Accordingly, in order that the audience identifies with the speaker, he or she must first identify with this audience. At the end of this process of adaptation, one might ask who exactly is being persuaded by whom? The extroverted rhetoric of persuasion is threatened by the solipsism of identification. It expresses only group introversion. The notion of “communion” proposed by the Treatise, may characterize the culmination of this process. This rhetorical concept of identification is totally foreign to the concept of identification defined in the framework of polyphony theory.

5. Who studies persuasion?

The characteristic difference of rhetorical argumentation cannot be defined by persuasion, for the simple reason that persuasion is an object claimed by many other disciplines, including the sciences and philosophy of cognition; neuropsychology as well as “neuro-linguistic programming”.

One year before the Treatise on Argumentation, Vance Packard published The Hidden Persuaders (1957), in which he developed a criticism of rational persuasion as socially ineffective. This criticism was first elaborated in the twenties by Walter Lippman (1922) and later by Edward L. Bernays (1928). In the wake of these books, but with quite different methods, neuromarketing came to focus on the issue of persuasion. To take a less controversial discipline, the analysis of persuasion also belongs to social psychology. This discipline counts among its fundamental objects the theoretical and experimental study of social influences: persuasion, convictions, suggestion, grip/influence, incitement… the formation and manifestations of attitudes, representations, and correlative transformations in the ways individuals or groups behave. The whole movement of the world, the material events, including scientific discoveries and technical innovations, along with the correlative flows of language, produce and rectify the representations, thoughts, words and actions of individuals and groups. The great classical studies of social psychology of persuasion published in the last century hardly mention rhetoric or argumentation. For example, neither the word rhetoric nor the words argument or argumentation appear in a collection of texts on the psychology of persuasion, entitled Persuasion (Yzerbit and Corneille 1994). The problem of persuasion can be legitimately invoked in relation to discourse, but the study of the process of persuasion, even in term of its linguistic aspects, may in no circumstances be carried out in the sole framework of rhetorical studies (Chabrol and Radu, 2008).

6. Persuasion as a general function of language

Just as rhetorical argumentation cannot be characterized by its persuasive function, it cannot be defined as the study of the persuasive language genres, insofar as the persuasive function is not linked to a genre but is coextensive with language use, S. Schematization.

From the general point of view of language functions, persuasion may be considered representative of the function of action on the recipient (call function, German Appell Funktion, Bühler [1933], or conative function, Jakobson [1960]). More specifically, Benveniste contrasts history (narrative) with discourse, and considers that the intention to influence is a characteristic of the latter category, discourse:

By contrast, we have in advance situated the plane of discourse. Discourse is to be understood in its broadest extension: every utterance supposes a speaker and a listener, and in the first the intention of influencing the other in some way. It is first of all the diversity of the oral discourses of every nature and of every level … but it is also the mass of the writings that reproduce the oral discourses or borrow their turns and ends. (Benveniste [1959], p. 242, my emphasis)

Nietzsche, in his lectures on rhetoric, generalizes rhetorical force to make it “the essence of language”:

There is obviously no unrhetorical “naturalness” of language of which one could appeal; language itself is the result of purely rhetorical arts. The power to discover and to make operative that which works and impresses, with respect to each thing, a power which Aristotle calls rhetoric, is at the same time the essence of language; the latter is based just as little as rhetoric is upon that which is true, upon the essence of things. Language does not desire to instruct, but to convey to others a subjective impulse and its acceptance. (In S. L. Gilman & al. C. 1989, p. 21)

This trend towards the extension of rhetoric as persuasion to any kind of talk is, moreover, compatible with all the classical definitions of rhetoric as a technique capable of developing the natural capacities of individuals.

7. Persuasion and the “colonization of minds”

The concept of rhetorical persuasion is built on the key idea that persuasion is intrinsically good, even if men and women have an unfortunate tendency to misuse the best things. The orator is placed in the elevated position of being a “good man, speaking well” and aspiring to universalize his visions and aspirations, an aristocrat of speech, while his audience is framed in the lower, insubstantial position of the undecided, because of poor reasoning and decision- making abilities, S. Enthymeme; Metaphor. The audience is considered barely capable of reaching an independent decision, needing guidance and easy prey to manipulators.

On the political and religious level, persuasion is the strictly correct term to use for propaganda. Propagandists and converters also introduce themselves as good persons eager to persuade, and might also count dictators and fundamentalists amongst the deeply self-convinced persuaders. S. Dissensus. In the early fifties, Domenach defined propaganda as the activities systematically organized “to create, transform or confirm opinions” ([1950], p. 8), while Perelman & Olbrechts-Tyteca focus on “the adherence of minds”; and to adhere is also the first step to becoming a member. A key difference between argumentation and propaganda is the means they use: argumentation uses “discursive techniques” (Perelman & Olbrechts-Tyteca [1958], p. 5), that is an overt, technique, while propaganda uses all the available means, both overt and covert, to achieve its goal, using not only discourse, but also images and all spectacular manifestations demanding a ritual collective action.

To persuade is to convert or, in Margaret Mead’s words, to “colonize minds” (Dascal 2009), to save the audience from some evil and direct them to some good, of which they were formerly neither persuaded nor convinced.

8. Arguing in an exchange structure

The theory of rhetorical persuasion is discussed in the context of an interaction without exchange (an addressed monologue, that is to say a one-turn interaction), which gives the public a largely passive role.
Pragma-Dialectic starts not from an opinion to be conveyed to a public but from a difference of opinion between two individuals, giving each opinion an equal value and chance to prevail. This theory “takes as its object the resolution of divergences of opinion by means of argumentative discourse” (van Eemeren and Grootendorst 1992, 18). Rule 1 opens up the space for debate and controversy:

Freedom – The parties must not obstruct the free expression of points of view or their questioning. (van Eemeren, Grootendorst, Snoeck Henkemans 2002, p. 182-183),

The debate reaches its rational goal if it can effectively eliminate either the doubt or the “inconclusively defended point of view”:

Closing – If a point of view has not been conclusively defended, the advancing party must withdraw it. If a point of view has been conclusively defended, the other party must withdraw the doubts it has expressed with respect to that point of view.” (Ibid.)

This leads to a consensus either on the opinion, or on its “withdrawal” (from the current interaction, from the other’s mind, etc.).
Interactional and cooperative approaches to argumentation consider that the viewpoint that one partner brings into the discussion and lays out for the appreciation of the other participants arguing their own perspective can be profoundly transformed by the encounter. Consensus can be achieved by merging primitive views or by co-constructing a third opinion, participants behaving like Hegelian evolutionary dialecticians progressing by synthesis of actual positions, and not as Aristotelian dialecticians, progressing by eliminating the competing position, S. Rhetoric; Dialectic.

9. Externalized persuasion

Persuading, that is to say changing the audiences’ minds, means changing the audience’s language. The persuasion experience leaves an inflection point in the discourse of the persuadee. The new discourse produced by a persuaded audience is characterized by its argumentative co-orientation with the persuader’s discourse. The persuadees ratify the persuader’s interventions; they adopt the speaker’s presuppositions, repeat his or her arguments, adopt his or her personal style, and, in the cases of “deep persuasion”, his or her tone of voice.

That is, persuasion can be externalized, to be analyzed, on the basis of linguistic evidence obtained by comparing the persuading and the persuaded discourses.

1 Quoted after Quintilien, I. O. = Institution oratoire, Trans. by J. Cousin. Paris: Les Belles Lettres,
2 Jean de La Bruyère, The Characters, or Manners of the Age. London: D. Browne, etc. p. 7. [Des ouvrages de l’esprit. In Les Caractères ou les mœurs de ce siècle, 1688] https://books.google.fr/books?id=6y9QiTEK1JAC&printsec=frontcover&dq=La+Bruyere+Characters&hl=en&sa=X&redir_esc=y#v=onepage&q=think&f=false (03-19-2017)

Some argument schemes are designated by Latin labels, S. A/Ab —; Ad —; Ex —. This entry lists the labels using the Latin preposition ad. In classical Latin, the preposition ad is constructed with the accusative and introduces a goal complement. The phrase “argument ad hominem” reads “argument addressing the person”.

According to Hamblin, the oldest scheme in this grouping is ad hominem, which appears in the Latin translations of Aristotle; this naming method was popularized by Locke ([1690]) and by Bentham ([1824]), and most of these terms seem to be nineteenth or twentieth century creations (Hamblin 1970, p. 41; p. 161- 162).

1. A list of “ad + N” arguments

Latin name of the Argument

Meaning of the Latin word(s)
• (When necessary a word-for-word translation)
• (English equivalent(s))
• Reference to the corresponding entry/ies

The argumentation from the absurd is a form of indirect evidence based on contradiction. This label includes a family of arguments concluding that an assertion or a proposal should be rejected on the basis of the indefensible consequences which would result from its adoption.

The general operation of reduction to the absurd corresponds to the following mechanism:

1. A claim, a proposal is put forward, as a working hypothesis, a possibility…
2. Consequences are drawn from this proposition, whatever they may be, causal, logical…
3. One of these consequences is deemed to be “absurd” in relation to some criteria, cf. infra
4. The initial proposal or hypothesis is rejected.

Argumentation to the absurd is not an argument from ignorance. An argument from ignorance concludes that P is true because we have failed to prove not-P, whilst an argument to the absurd concludes that P is true because it has been shown that the proposition not-P is false, and that between P and not-P, only one can hold true. This corresponds to a case-by-case argument in a situation where the number of cases is reduced to two: P is true or not-P is true; but not-P is false, so P is true. S. Apagogic argument; Contradiction.

2. Varieties of absurdities

There are as many kinds of reduction to absurdity as modes of deduction and reasons to evaluate a consequence as inadmissible. The qualification as absurd may thus apply to:
— Mathematical consequences. One clearly sees the variety and the diversity of what is called the “absurd” in argumentation by contrasting these forms with the demonstration from the absurd, where absurd means “contradictory”, cf. infra.

— Logical or semantical consequences. The consequences analytically derived, from the very meaning of the expression lead to a semantic difficulty, S. Dialectic; Opposites; Consequence.

— Causal consequences. In the physical domain and natural experience, the effects predicted by the hypothesis are not attested, S. Refutation by the opposite. The refutation by an attested fact, different from the theoretically expected fact, is a kind of refutation from the absurd.

— Practical consequences. As soon as one turns from the scientifically established causal link to the “causal story” as constructed in a pragmatic argument, however, the speaker intervenes through his or her positive or negative valuation of the consequences. The consequence is then:

— Contrary to the intended goals, the effects of the proposed action are perverse; the measure is counterproductive, contrary to various interests.

— Inadmissible from the point of view of common sense, law, or morality, S. Apagogic; Ad Incommodum.

Pragmatic refutation by negative consequences is opposed to a measure by showing that it will have negative consequences unforeseen by the individual who proposes the measure, and that these drawbacks will prevail over any possible advantage.
The argument is strengthened  if the opponend can show that these  alledged negative consequences are not just  collateral effects, but are in fact  diametrically opposed to the expected positive effects:  the measure proposed to cure the patient will in fact strengthen her disease.

3. Demonstration by reduction to the absurd

Proof by the absurd, or by contradiction, is based on the principle of the excluded middle, according to which “A or not-A” is necessarily true. The rea- soning is based not on the proposition A that we want to prove, but on its negation, not-A.

The negation, not-A, is provisionally admitted and its consequences are de- duced; these consequences lead to statement A. But the conjunction “A and not-A” contravenes the principle of contradiction; thus, not-A is false, and A is necessarily true.

In the language of implication, we are in a situation where “A → non-A’. According to the principle of “one can deduce anything from the false”, this implication is true only if A is false.

It can be shown by reduction to the absurd that “the square root of 2 (the number whose square is 2, noted by the symbol √2) is not a rational number” (proposition A).

(1) Suppose that “the number corresponding to √2 is a rational number” (proposition not-A).
(2) By definition, a rational number can be written in the form of a fraction “p / q”, where p and q are prime numbers (a prime number can be divided only by itself and 1).

From this hypothesis, it can be deduced that both p and q are even; Therefore, they have 2 as a common divisor, which is contradictory to the initial hypothesis.

(8) Conclusion: hypothesis (1) is false, and √2 is not a rational number.

The demonstration by the absurd is an indirect method of demonstration. It has not been proved that A is true, but only that not-A is false. This reasoning is by no means permitted by all specialists, “if the classical mathematicians consider the proof by the absurd as valid, the intuitionists reject it: in order to prove a, they say, it is not enough to establish that not-(not-a)” (Vax 1982, Absurd). We see that the demonstrative character of a demonstration can be discussed.

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  Lat. absurdus, “absurd”. Argument ad absurdum, ab absurdo, ex absurdo; or reductio ad absurdum, “reduction to absurdity”, under different forms: reductio ad impossibile, “reduction to the impossible”; r. ad falsum, “r. to the false”; r. ad ridiculum, “r. to the ridicule”; r. ad incommodum; “r. to the undesirable”.
  

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Latin labels are used to name arguments and fallacies. This practice, although not systematic, is common in modern texts, not exceptional in law, and some traces remain in contemporary usage.

A few of these labels belong to the usual vocabulary of argumentation theory:

argument ad hominem, a fortiori, a contrario, a pari…

The English counterpart of the Latin word is often transparent:

argument e silentio, argument from silence.

Nonetheless, some labels remain opaque when one is not familiar with Latin:

argument ad crumenam, argument to the purse.

The current translation of these Latin labels may be questionable. The label argument ad verecundiam is often translated as “argument from authority”, while the Latin word verecundia means “modesty, humility”. For Locke, who introduced this label, the ad verecundiam argument is not precisely a sophism of authority but of submission to authority, S. Modesty.

This terminology is no longer spontaneously understood. In many cases, this piecemeal Latin appears gibberish and even ridiculous, particularly when well established, or more readily understood English terms can be used to refer to the same argument scheme.

This continued use of Latin labels, however, is due to the power of Latin as the language of law, theology, philosophy and traditional logic. This designation system for argumentation parallels the one which is well established and currently used for the designation of rhetorical figures. Latin has provided a common technical language for everyday reasoning, whilst giving the theoretical discourse some fragrance of Ciceronian authority. This use of Latin is altogether comparable to the contemporary use of English in countries where English is not the native language.

Three main types of Latin phrases can be distinguished.

1. Prepositional labels using the prepositions ab /a — ad — ex

Some arguments or fallacies are designated, in contemporary texts, by prepositional phrases having the following structure:

Latin Preposition + Latin Noun + argument

Sometimes, the Latin word “argumentum” replaces argument.

Latin is an inflected language; in prepositional phrases, the preposition imposes a specific grammatical case on the following noun, marked by a morphological variation at its end.

The three most used prepositions are ab, ex, and ad.

— The preposition ab (or a before consonant) means “from, pulled of, drawn from”:

a contrario argument, argument from the contrary.

—The preposition ad, means “to, towards, for »:

ad personam argument, argument to the person.

— The preposition ex means “from, out of”, indicating the origin:

Argument ex datis: argument drawn from what is admitted by the audience.

Ex labels are less common.

Occasionally, other prepositions can be found:

per: per analogiam argument, argument by analogy;
in: argument in contrarium, argument from the opposites;
pro: argument pro subjecta materia, argument relative to the subject matter. S. Subject matter.

From a semantic point of view, there is a directional contrast, origin vs. purpose, between the prepositions ab and ex on the one hand, and ad on the other hand:

ab, ex + Latin noun + argument = argument based on —, using —
— ad + Latin noun + argument = argument targeting —.

Ab, ad and ex compete in the designation of some arguments, with the same meaning:

ab auctoritate or ad auctoritatem argument;
ab absurdo or ad absurdum or ex absurdo argument.

The argument schemes designated by each of these labels have no common semantic basis. Many ad tags have been introduced in the modern period. Sometimes, they  refer to very specific contents, in particular, to appeals to emotion or to a subjective position, whilst the labels ab and ex are never used in this sense.

The following entries list the Latin labels according to the preposition head of the noun phrase, give some equivalent of the Latin terms, and refer to the corresponding entry or entries:

Ab — Arguments (A Contrario, etc.)
Ad — Arguments (Ad Ignorantiam, etc.)
Ex — Arguments (Ex Concessis, etc.)

These lists are taken from Bossuet ([1677]), Locke ([1690]), Bentham ([1824]), Hamblin (1970); Perelman & Olbrechts-Tyteca ([1958]), and from the Internet. They do not claim to be exhaustive.
Modern Latin labels are presented along with ancient ones, as they were used by Cicero, Quintilian and Boethius, and sometimes incorporated unchanged by modern authors. Examples of this original terminology may be found under the entry Typologies (II): Ancient.

2. Other Latin phrases

Less frequently, various Latin phrases are used to refer to classical Aristotelian fallacies:
— Fallacy of omission of relevant qualification or circumstances; undue generalization of a limited claim:

Fallacy a dicto secundum quid ad dictum simpliciter: a reasoning concluding from a qualified statement (limited in scope) to a generalizing statement (absolute).

Lat. dictum “word; maxim; sentence” here: “assertion”; Lat. secundum quid “according to something”; Lat. simpliciter, from simplex, “simple”.

This formula is abbreviated as “secundum quid fallacy”, S. Circumstances.

— Fallacies of false cause, that is to say, of poor construction of the causal relation, S. Causation; Cause-Effect: The causal link:

Non causa pro causa: “a non-cause is taken for a cause”. E1 is said to be the cause of E2, although this is not the case.
Cum hoc, ergo propter hoc: “At the same time as, thus because of ”.
From the fact that E1 and E2 are concomitant, one wrongly infers that they are causally linked.
Post hoc, propter hoc ergo: “later, thus because of”: from the fact that E1 always occurs before E2, one wrongly infers that E2 is due to E1.

— Fallacy of vicious circle:

Petitio principii, Lat. petitio, “demand”; principium “principle”: “request to grant (something equivalent to) the claim which is actually disputed”

The language of law uses Latin phrases and expressions to refer to argumentative principles, for example:

eiusdem generi: lat. idem, “the same”; genus, “genus”. Argument from the identity of genus; S. Genus; Juridical arguments.

3. A mocked pattern

In Tristram Shandy, Sterne mentions the arguments ad verecundiam, ex absurdo, ex fortiori, ad crumenam and the argumentum baculinum (ad baculum) and asks to add to this list the argumentum fistulatorium, which he claims to have invented.

— There lies your mistake, my father would reply; — for in Foro Scientiae there is no such thing as MURDER, —’tis only DEATH, brother.
My uncle Toby would never offer to answer this by any other kind of argument, than that of whistling half a dozen bars of Lillabullero.—–You must know it was the usual channel thro’ which his passions got vent, when anything shocked or surprised him; — but especially when any thing, which he deem’d very absurd, was offerd.

As not one of our logical writers, nor any of the commentators upon them, that I remember, have thought proper to give a name to this particular species of argument, — I here take the liberty to do it myself for two reasons. First, That in order to prevent all confusion in disputes, it may stand as much distinguished for ever from every other species of argument — as the Argumentum ad Verecundiam, ex Absurdo, ex Fortiori, or any other argument whatsoever: — And, secondly, That it may be said by my children’s children, when my head is laid to rest, — that their learn’d grandfather’s head has been busied to as much purpose once, as other people’s; — That he had invented a name, — and generously thrown it into the TREASURY of the Ars Logica, for one of the most unanswerable arguments in the whole science. And, if the end of disputation is more to silence than convince, — they may add, if they please, to one of the best arguments too.

I do therefore, by these presents, strictly order and command, That it be known and distinguished by the name and title of the Argumentum Fistulatorium, and no other; — that it rank hereafter with the Argumentum Baculinum and the Argumentum ad Crumenam, and for ever hereafter be treated of in the same chapter.

As for the Argumentum tripodium […] Laurence Sterne The Life and Opinions of Tristram Shandy, Gentleman [1760]1

Lillibullero is a famous Irish march; the fistula is a panpipe (Gaffiot, Fistula). Uncle Toby’s maneuver is an excellent, although rude, strategy to annihilate a discourse, S. Destruction of discourse; Dismissal.

1 In The Complete Work ofLaurence Sterne. Delphi Classics, 2013. P. LV