COUNTER ARGUMENTATION

The term counter-argumentation can be used to refer to any kind of discourse, argued refutation or objection, that openly opposes an argument. A simple “No!” can be considered as a counter-argumentative move, even a non-verbal expression of rejection that is clearly interpretable as such.

In contrast to direct refutation, a specific “argumentation vs. counter-argumentation” situation occurs when the refutation is reciprocal and indirect:

— Speaker S1 argues for proposition M.
— Speaker S2 counter-argues for proposition R, which is incompatible with M:

S1 — Let’s build the new school here, the land is cheaper.
S2 — Let’s build the new school there, the students will waste less time commuting

S2 makes a counter-proposition R, which is an alternative to M.

Argumentation and counter-argumentation play a reciprocal role in refutation. In such a polarized situation, the fact of providing a reason for doing R that is incompatible with M, serves as a reason for not doing M. Any good reason for supporting R is seen as a counterargument to M.

The argumentation / counter-argumentation structure can correspond to an emerging argumentative situation, or to the moments when the participants present and argue their position without considering the antagonist’s proposal, which can occur at any time in a concrete argumentative situation.

An argued position can be presented in isolation in an autonomous text without refuting or even mentioning an existing counter-argumentation. Such a strongly assertive strategy avoids the paradoxes of refutation, but can be seen as a kind of contempt for the argument of the opposing party, see Question; Contradiction; Antithesis; Dismissal.

As with weak refutations, a weak counter-argumentation strengthens the position being attacked. In the following passage, Noam Chomsky considers that his opponent, the philosopher Hillary Putnam, has failed to develop a counter-argument, not even a counter-proposal, and argues that this shows that he, Chomsky, must be right:

So far, in my view, not only [Putnam] has not justified his positions, but he has not been able to clarify what these positions are. The fact that even such an outstanding philosopher fails to do so, may allow us to conclude that…
Noam Chomsky, [Discussion on Putnam’s Comments], 1979.[1]

Praising one’s opponent as an « exceptional philosopher » is a characteristically eulogistic and perfidious accompaniment to this kind of refutation:

By refuting you, I’m not refuting just any philosopher, but a Master – and therefore, a fortiori, all the philosophers who oppose to my views.

S. Politeness; Ignorance; Paradoxes.

[1] Noam Chomsky, Discussion sur les Commentaires de Putnam. In Piattelli-Palmarini M. (ed.). Théorie du Langage, Théorie de l’Apprentissage. Paris: Le Seuil. 1979. P. 461.
[Discussion of Putnam’s Comments. In Piattelli-Palmarini M. (ed.). Language Theory, Learning Theory.]

COOPERATIVE PRINCIPLE

According to H. P. Grice, the intelligibility of the conversation is governed by “a rough general principle which participants will be expected (ceteris paribus) to observe”, namely:

‘Make your conversational contribution such as is required, at the stage at which it occurs, by the accepted purpose or direction of the talk exchange in which you are engaged’. One might label this the Cooperative Principle. (1975, p. 45; capitalized in the text).

This “Principle of Cooperation”, is specified in four forms, “Quantity, Quality, Relationship and Manner” (ibid.).

— Quantity: “I expect your contribution to be neither more nor less than is required” (ibid.).
— Quality: “I expect your contribution to be genuine and not spurious” (ibid.). This can be compared to the requirement of accuracy mentioned in the pragma-dialectical rule 8; the same concern is also found in Hedge’s rule 1 “For an honorable controversy”, S. Rules.
— Relation: “I expect a partner’s contribution to be appropriate to immediate needs at each stage of the transaction” (ibid.). This concerns in particular the relevance of the turn in relation to the present topic of dialogue and action. Grice recognizes the difficulty of identifying what is relevant in an exchange. The pragma-dialectical “Relevance rule” deals with this same requirement (van Eemeren, Grootendorst (2004, p. 192). S. Relevance; Rules.
— Manner: “I expect a partner to make it clear what contribution he is making” (ibid.). This entry may cover the rejection of obscurity of expression and action; of ambiguity (the first of the Aristotelian fallacies); of the unnecessary verbosity, corresponding to the fallacy of verbiage.

Grice claims that his principles capture the rational character of conversation:

One of my avowed aims is to see talking as a special case or variety of purposive, indeed rational behavior. (Id., p. 47)

as well as its reasonable character: Respect these principles is not merely “something that all or most do IN FACT follow, but as something that it is REASONABLE for us to follow, that we should not abandon” (ibid., p. 48; capitalized in the text).

These four principles can be compared with those of normative theories of argumentation, see Rules.

A statement that violates Grice’s principles is not eliminated as fallacious, but is understood as an indirect speech act. When a participant notices that something does not conform to a conversational rule, the response is not to accuse the partner of making an irrelevant or irrational contribution, but to engage in an interpretive process to determine why he or she has violated the conversational rule. The analysis of fallacies returns to this interpretive orientation whenever it adds to its logic pragmatic considerations that take into account the contextual conditions of the exchange.

In an argumentative situation, the concept of cooperation is a strategic issue that is redefined by the participants, who are not necessarily willing to cooperate, for example in their own refutation. There is nothing scandalous or irrational about this, as long as the partners are aware that they are in such a deliberately opaque context, see Politeness. Rational, reasonable, as well as honorable rules for discussion are intended to restore or strengthen cooperation in such antagonistic contexts.

CONVERSION

1. Logic

In logic, two propositions are converse (in a relation of conversion) if they swap their subjects and their predicates. “As are Bs” and “Bs are As” are converse propositions. The converse of a true proposition is not necessarily true, see Proposition, §3.2

2. Grammar and argumentation

In grammar, the conversion transformation can be applied to any binary structures. Restructuring an expression of the opponent, that is, playing with his or her words, can help to reverse the global orientation of his or her discourse, according to the mechanisms of the antimetabole, see Orientation Reversal.

Well, you know, this talk about the so-called pleasures of retirement is just empty talk to cover up the retirement of pleasures.
Personally, I’d prefer a frightful/terrible end to this endless fright/terror.
González, on Kohl ‘He fought for a European Germany, never again a German Europe.” (El País, 07-01-2017)

One can radically counter-argue a proposition by emphatically supporting its converse, S. Causality (II); Analogy:

S1 —     A is the cause of B; A is like B; A mimics, copies B.

S2 —     Not at all! B is the cause A! B is like A; B copies A.

In the same way, a sweeping defense strategy consists in converting the roles of accuser and accused, first by applying the reciprocity principle, “it takes one to know one”:

You blame me (for X), I blame you (for Y)
You filed a complaint against me (for X), I file a complaint against you (for Y).

and, second, by converting the position about the same criminal offense:

You are the culprit, you did it, you, who accuse me!

The child’s reply “he who says it did it” converts the accusation, , and justifies the counter-accusation:

S1 — You stole the orange!
S2 — No, you stole it, who says it he did it!

The fact that S1 accuses S2 is used by S2 as an argument to accuse S1. see Reciprocity; Stasis.

CONVERGENT, LINKED, SERIAL Argumentation

The conclusion of an argumentation is usually expressed in a single statement, possibly expanded in a short closing speech, see Argument – Conclusion.
The arguments, i.e., the part of the argumentative discourse that supports and sometimes surrounds the conclusion, can be considerably developed along quite different lines:

— Convergent argumentation, also called multiple argumentation, combines several co-oriented arguments.

— Linked argumentation, also called coordinate argumentation consists of several statements that combine to form an argument.

— Serial argumentation, also called subordinate argumentation consist of a sequence of argumentations, such as the conclusion of the first one is taken as an argument to support a second one and so on, see sorite.

One caveat: these categories are logical categories; they assume that arguments correspond to clean-cut, continuous explicit linguistic segments, just like premises in a logical reasoning. This is not the case in ordinary language, where arguments can be intertwined, an argument can contain another argument,  and episodes of expository language can take a distinctly argumentative turn. See Tagging.

CONVERGENT argumentation

Convergence is a basic mode of organization of complex discourse to support a conclusion, S. Convergent, Linked, Serial.
Two or more arguments are convergent when they independently support the same conclusion. The arguments are said to be co-oriented, and the argumentation is said to be convergent or multiple.
“Two reasons are better than one”: In a convergent argumentation, a claim is defended on the basis of several arguments that, taken separately, may be relatively weak, but, taken together, combine to make a stronger case: “My computer is getting old, there are discounts on the price of my favorite brand, I’ve just got a bonus, I’m going to buy one! ”.

The above diagram shows each argument is represented as a whole. The following diagram spells out the transition laws according to Toulmin’s proposal, S. Layout; compare with linked argumentation:

As well as pro-arguments, counter-arguments can converge to refute a claim, see Script.

This open structure defines the argumentative network, in contrast to the demonstrative chain. In the demonstrative chain, each step is necessary and sufficient; if one step is invalid, the whole construction collapses. In the case of the argumentative net, if one link in the mesh is broken, the net can still be used to catch fish, at least the biggest ones.

In a convergent argumentation, the organization of the sequence of arguments is relevant. If the arguments are of a very different strengths, a ridiculous or a weak argument next to a strong one risks damaging the whole argumentation, especially if that argument ends the enumeration:

He’s a great hunter, he killed two deer, three wild boars and a rabbit.

In classical rhetoric, the theory of the general organization of discourse (Lat. dispositio) discussed the supposedly different persuasive effects of the various possible textual arrangements of converging arguments of different strength, S. Rhetoric.

Convergent arguments can be merely listed (paratactic disposition):

Arg, Arg and Arg, so Concl

They can be connected by any listing or additive connective:

first, Arg1; second, Arg2; third, Arg3; so Concl.
Additionally, also, in addition, let alone, moreover, not only, 
besides

Connectives such as besides, not only, in addition, let alone, not to mention… not only add argument(s) upon argument(s), they present them as if each one was actually sufficient for the conclusion, and only added just “for good measure” (Ducrot & al. 1980, pp. 193-232):

No, Peter will not come on Sunday, he has work, as usual, besides his car broke down.

The additive approach holds that each argument contributes a piece of truth, and that these pieces can be arithmetically added together, to form a large, conclusive discourse. Speech activity theory holds that, by default, an argument is presented as sufficient, and that the addition of other arguments actually follows the logic of commercial presentation to consumers (the audience), i.e. the speaker offers the audience a series of arguments he considers equally satisfying and self-sufficient.

Case-by-case argument  — To refute the conclusion of a convergent argumentation, each of the arguments supporting that conclusion must be refuted. Thus, a convergent argument is countered by a case-by-case rebuttal, limited to the cases presented by the proponent.

CONTRARY and CONTRADICTORY propositions

1. Definition

In logic, the « square of oppositions » connects the affirmative and negative propositions, the universal and particular propositions, according to a set of immediate inferences, among which are the relations of contradiction and contrariety, see Proposition §4

— Two propositions P and Q are contradictory if they cannot be simultaneously true or simultaneously false; that is, one of them is true, and the other is false, as shown in the  following truth table (see Logical connectives)

In the logical square, the proposition « All M are N » and « some M are not N » cannot be simultaneously false true of false; they are contradictory propositions.
A proposition and its negation are contradictory proposition.

— Two propositions P and Q are contrary when they cannot be simultaneously true, but can be simultaneously false.

In the logical square, the proposition « All M are N » and « No M is N » can be simultaneously false when « some M are N« ; they are contrary propositions.

These terms can easily be confused. The easiest way to avoid confusion is to relate the relations of contrariety and contradiction to two kinds of universes, thus defining two kinds of opposites. Let U be a universe containing a number of individuals.

(i) Contradictories — In the case of contradiction, the opposition is within a two-dimensional universe, such as the traditional system of genre: “— is a man” and “— is a woman” are contradictory predicates in this system. In a non-traditional genre system, they are contrary propositions.

U is a two dimensional universe; two properties P₁ and P₂ are defined upon this universe, such as:
— Every member of this universe possesses either the property P₁ or the property P₂:
— No one possesses both properties P₁ and P₂: no one is both (P₁ & P₂). This is noted as (P₁ W P₂), with the symbol ‘W’ for “disjunctive or”.

P₁ and P₂ are complementary properties; they divide the universe U into two complementary (non-overlapping) sets.
— P₁ and P₂ are contradictories (opposites); they stand in a relation of contradiction.

(ii) Contraries — In the case of contrariety, the opposition is within a multidimensional universe such as the universe of colors. “— has white hair” and “— has red hair” are contrary predicates: a person cannot have both white and red hair (notwithstanding the case of badly dyed hair roots); and he may have brown hair.

U is an n-dimensional (more than two dimensions) universe: P₁, … P_i, … P_n.

— Every member of this universe has one of these properties, P_j; that is, is either a P₁ , … or a P_i, … or a P_n.
— No one has two or more properties P₁ , … P_i, … P_n, that is, no one is both (P_k & P_l).
— P₁ , … P_i, … P_n are contraries; they are in a relation of contrariety.

To sum up, semantically related predicates, or properties, are opposite if they exhaustively divide their reference universe into a series of non-overlapping sets. If there are just two such properties, they are said to be contradictory properties; if there are more than two, they are said to be contrary properties. So, contradictories are the limit case of contraries.

2. Refutation by substitution of contrariety to contradiction

It follows that an assertion based on a contradiction can be refuted by showing that the universe under discussion should not be considered as two-dimensional, but multi-dimensional. This seems to be the case in the following example.

In 1864, Pope Pius IX published the Syllabus, that is, a collection or a catalog of the Vatican’s positions on “modernist” ideas. Considered retrograde, the Syllabus was strongly attacked by “the modernists. In 1865, Mgr. Dupanloup, defended the Syllabus in the following terms; “they” refers to the modernists.
It is an elementary rule of interpretation that the condemnation of a proposition, condemned as false, erroneous and even heretical, does not necessarily imply the assertion of its contrary, which could be another error, but only of its contradictory. The contradictory proposition is the one that simply excludes the condemned proposition. The contrary proposition is the one that goes beyond the simple exclusion.
Now! It is this general rule that they have apparently not even suspected in the unthinkable interpretation of the Encyclical and the Syllabus that they have been giving us for the past three weeks. The Pope condemns this proposition: “It is permitted to refuse obedience to legitimate princes” (Prop. 63).
They claim that, according to the Pope, disobedience is never permitted, and that it is always necessary to submit to the will of princes. This is a leap to the extreme of the contrary, and ascribes to the Vicar of Jesus Christ, the most brutal despotism, and slavish obedience to all the whims of the kings. This is the extinction of the noblest of all liberties, the holy liberty of souls. And that’s what they claim the Pope said!
Félix Dupanloup, Bishop of Orleans, [The Convention of September 15, and the Encyclical of December 8 [1864] ] (1865) [1].

Reasoning on the content
There are several possible responses for someone who receives an order from a civil authority (« the prince »). Let’s look at the following three:

a. Obey
b. Disobey = « refuse to obey »
d. Appeal against the order, to a higher authority than the one who gave the order: the latter is not legitimate; they abused their power, etc.

We do not mention the case of the interpretation (§3) of the order, which is probably too specific. Reasons such as the conscience clause are not considered at this time.

1. « The Pope condemns this statement: ‘It is permissible to refuse obedience to legitimate princes‘« .

<NEG (refuse obedience)> is contradictory to, i.e., exludes <refuse obedience>

The syllabus excludes option b. « refuse to obey », but leaves open all other opposites of obey. In other words, excluding refusal to obey is not imposing obedience.
« The contradictory proposition is the one which simply excludes the condemned proposition« . It does not say whether one must obey the command or protest against it.
Similarly, <NEG having blonde hair> is contradictory to, that is, excludes <having blonde hair>, but it does not say that the hair in question is brown or chestnut.

2. »The contradiction is that which goes beyond this simple exclusion » of the possibility of disobedience. It claims that this exclusion is tantamount to a prohibition of disobedience.
Modernists « leap to the extreme opposite« , misinterpreting what is a contradiction (three possibilities) as an opposition between two exclusive possibilities. They consider only two cases: either obey or disobey, they omit the case of appeal against the command.

Reasoning on the modality
Is the universe of the Syllabus binary or multidimensional? Let’s consider a position X.

— If it is a binary opposition, “allowed vs. forbidden”, then the propositions “it is permitted (to refuse obedience)” / “it is forbidden (to refuse obedience)” are contradictory: only one of these propositions is true. If we condemn the proposition “it is permitted to refuse obedience to legitimate princes”, then we have to conclude that the contradictory is true, that is to say, “it is forbidden to refuse obedience to legitimate princes”, or, in other words: “we must always bow our heads under the will of the princes.”
Thus, for Dupanloup, the malevolent “modernists” substitute contradictories for contraries, which he describes as “jumping to the last end of the contrary”, I understand a leap to the (binary) contradiction, which is the limit of (multidimensional) contrariety.
He accuses the modernists of reframing the Pope’s position, using a strategy of absurdification (an exaggeration to the point of absurdity), see exaggeration.

— If the position X enters a three-dimensional universe, as “required / permitted (indifferent) / forbidden” then the propositions “It is permitted / it is forbidden” (to refuse obedience) are not contradictories but contraries: they are not simultaneously true, but they can be simultaneously false, e.g. if X is indifferent. The conclusion “If X is not opposed, X is demanded” is not valid. If we condemn “It is permissible to refuse obedience to legitimate princes” then we can only conclude one or the other of these opposites:

It is obligatory to refuse obedience to legitimate princes.
It is forbidden to refuse obedience to legitimate princes.

Since it would be difficult to admit that Pius IX, or anyone else, prescribes a systematic duty of disobedience to the legitimate rulers, we are left with the other member of the disjunction, that is, “X is forbidden.

One could also put in parenthesis the alternative obey/desobey, neither obey nor disobey, but file an appeal against the order, arguing that the prince is not legitimate, or not empowered to issue this kind of order, or that the order is harmful to the common good, etc.
This might be worth a try, if the appeal is not suspensive, and if the prince is interested in discussing his policies with the people he orders.

[1] Quoted from Félix Dupanloup, La Convention du 15 Septembre et l’Encyclique du 8 décembre [1864]. In Pius IX, Quanta Cura and the Syllabus. Paris: Pauvert, 1967. P. 104-105.

[2] https://www.nd-chretiente.com/dossiers/pdf/articles/2010_la%20vertu%20d%27obeissance.pdf St Gregory sets the following limits to obedience:
No one is obliged to obey men in everything. The limit of obedience is the abuse of power.
Resistance to an abusive command is justified when its execution would cause certain harm to the common good.
Such an abuse may occur when the order comes from an authority that is not legitimate, or when the order comes from a legitimate authority but encroaches on a sphere that is not its own. There is also an abuse of power when the order of a legitimate superior, who commands within the limits of his authority, is contrary to the order of a higher superior: this establishes the duty to resist an order or law that is contrary to natural law or a formal order of God.

CONTRADICTION

1. In dialogue, a contradiction emerges when a first turn  of speech is not ratified by the partner’s next turn.
Emerging contradictions can be resolved on the spot through a series of adjustments and arrangements, playing with the margins of indeterminacy and windows of opportunity left by ordinary language and actions.
The contradiction is open when both parties produce oppositional (anti-oriented) turns of speech. When the opposition is thematized and ratified by both participants, an argumentative situation arises.

See Disagreement; Argumentative Question; Stasis;
Denying; Refutation; Counter-argumentation.

2. Contradiction in speech: ;Ad hominem; Consistency;  Absurd.

3. Contradiction between terms, see opposites.

4. Logical treatment of contradiction: Non-contradiction principle;
Propositions contrary and contradictory.

CONSISTENCY

The basic expression of argumentative coherence or consistency is non-contradiction,  see non-contradiction; absurd; ad hominem.

The consistency requirement is particularly important in systems of regulation of human behavior, religion, law, and  ordinary institutional or family rules.

The consistency requirement is expressed a contrario in the refutation strategy mentioned in Aristotle’s Rhetoric, topic # 22:

Another line of argument is to refute your opponent’s case by noting any contrast or contradiction of dates, acts or words that it anywhere displays. (1400a15; RR p. 373).

1. After the event as before

Topos ≠5, “On the consideration of time” appeals to consistency. This theme is not explicitly stated, but is presented by two examples:

If before doing the deed I had bargained that, if I did it, I should have a statue, you would have given me one. Will you not give me one now that I have done the deed? (Rhet, II, 23, 5; RR, p. 361).

The situation is this:

1. 1. X (asks nothing and) performs a deed (perhaps an impulsive heroic act)
   2. Afterwards, he asks for a reward.
   3. Argument: if he had asked before, a reward would have been agreed upon
      

The hero feels that all feats must be paid for as such. It is as if the definition of the word feat includes the characteristic “deserves a reward”:

L1:   — If you do it, you’ll get…
L2:   — I have done it, and done well, so give me …

This argument scheme express the disappointment of someone who reports finding a wallet and does not receive a reward.

2. Human (in)consistency

Consistency may be the rule, but inconsistency is a fact of life. This is what the argument scheme #18 says:

Men do not always make the same choice on a later and on an earlier occasion, but reverse their previous choice. (Rhet, II, 23, 18; RR, p. 371)

This argument scheme is materialized in the following enthymeme:

When we were exiles, we fought in order to return; now that we have returned, it would be strange to choose exile in order not to have to fight. (ibid.)

The enthymeme seems to assume the following situation. In the past, the exiles fought to return home, and they returned. In the present situation, they are suspected of refusing to fight, and preferring exile. They deny the charge with this enthymeme, which is a claim of consistency, as in:

You fought for this position, now you can’t accept being thrown out like this!

This is a kind of positive ad hominem argument; it may presuppose an a fortiori: “We fought to return to our homeland, a fortiori we will fight not to be thrown out of it!”
The accusers reply “Men do not always make the same choice, etc.”

The opposing party argues from a contrary view of human nature; the two opinions “men are constant / inconstant”, are equally probable (see ibid I, 2, 14; p. 25). They can thus be the basis for two antagonistic conclusions.

S. Ad hominem; A fortiori.

3. Consistency of the legal system and stability of the objects of the law

Lat. arg. a cohærentia, de cohærentia, “to form a compact whole”.

3.1 Principle of coherence of laws, a cohærentia

This principle requires that, within a legal system, one norm cannot conflict with another; the system does not allow antinomies. An argument can therefore be rejected if it leads to the view that two laws are contradictory; this is a form of argument from the absurd.
In practice, this principle excludes the possibility of the same case being decided in two different ways by the courts.

According to this principle, if two laws contradict each other, they are only seemingly contradictory, and, consequently, they must be interpreted in such a way as to eliminate the contradiction. If one of these laws is obscure, it must be clarified by reference to a less doubtful one.

The argument a cohærentia is used to resolve conflicts of norms. To prevent such conflicts, the legal system provides for adages, which are meta-principles of interpretation, such as “the most recent law takes precedence over the oldest”. These adages are interpretive meta-principles, coming from Roman law and sometimes expressed in Latin: “lex posterior derogat legi priori”.

3.2 Principle of the stability of the object of the law, in pari materia

Lat. in pari materia: lat. par, “equal, like”; materia, “topic, subject” argument “in a similar case, on the same subject”.

The argument a cohærentia deals with the formal non-contradiction of laws in a legal system. The argument in pari materia, or argument “on the same subject”, expresses a substantive form of consistency. It requires that a law be understood in the context of other laws that have the same goal or refer to the same beings, that is to say the same beings (persons, things, actions) or the same subject.

The given definition of the subject of the law must be stable and consistent. The application of the argumentation a pari presupposes the stability of the legal categories. see Classification; A pari.
This principle of consistency leads the legislator to harmonize the system of laws on the same subject. What constitutes the same subject and the set of laws on the same subject may be questioned. For example, anti-terrorist laws, are a package of different legal provisions, for which it is necessary to ensure that the definition of “terrorism” remains the same in each of the passages that use the term. If this is not the case, these laws need to be made consistent, which means that they themselves need to be underpinned by a consistent policy.

The two topoi discussed in the two following paragraphs are taken from Aristotle’s Rhetoric. They are based on the two incompatible, but equally recognized substantive topoi, “human conduct is, or ought to be consistent” and “human conduct is inconsistent”.

4. Argument from narrative inconsistency

As a special case of ad hominem argumentation, showing inconsistencies in the accusatory narrative can refute an accusation:

S1:    — You are the heir, you benefit from the crime, you killed to inherit!
S2:    —Then, I should have killed the other legatee too.

The prosecution will have to prove that S2 also intended to murder the other heir, or otherwise find an alternative motive. The defense starts from the hypothesis proposed by the prosecution to show that the actions of the suspect do not fit into the proposed scenario; the accusatory narrative contains flaws or contradictions.

The incoherent accusation argument exploits a basic principle of practical rationality: the suspect’s actions must be consistent with his or her claimed goal. The defendant can refute the accusatory narrative by showing that, according to hat narrative, he acted inconsistently:

You say I’m the killer. But it has been proven that just before the crime, I spent an hour in the cafe in front of the victim’s house, everyone saw me. It is not consistent behavior for a murderer to show himself at the scene of the crime.

Any weakness found in the prosecution’s scenario can then be used to exonerate the defendant.

The principle of consistency of laws and the principle of stability of the subject of the law concern the coherence of the legal system. The argument from the inconsistency of the narrative exploits the resources of narrative rationality: all the narratives offered as excuses, all the narratives mixed with argumentation are vulnerable to this kind of refutation.
Conversely, the argument seems plausible and reasonable because the story is so, and because the speaker knows how to tell it.

The strategies described in the topoi # 22, 25 and 27 and probably 18 (see above) of the Rhetoric are relevant to this discussion (Aristotle, Rhet., II, 23), see Collections 2.

EFFECT-TO-CAUSE Arg.

The word consequence can mean:

— Effect, referring to a causal, cause-effect relationship, see causality.
— Consequent, referring to a logical, antecedent-consequent relationship, see connectives (§Implication)

1. Effect-to-Cause Argument

Other expressions can also be used as well, such as argument by the effect, or from the effect to the cause, see also a priori, a posteriori.
The effect-to-cause argument works backwards from the effect to its cause. Data is considered to be the effect of a hypothetical cause, which that can be reconstructed based on the data combined with a known causal relationship between this type of fact and its cause.

You have a fever, therefore you have an infection

— Argument: A confirmed fact t, the patient’s temperature. This fact t belongs to the category of facts or events T, “having a temperature”, as defined by medicine. This is a categorisation process.
— Causal law: There is a known causal law linking I-facts “having an infection” to T-facts, “having a temperature.”
— Conclusion: t has a I-type cause, an infection, and the patient should be treated accordingly.

This corresponds to the diagnostic process. One might speak of diagnostic reasoning, a type of abduction.

The effect (the temperature) is the natural sign of the cause. These natural, palpable, effects provide a basis for argument from natural signs:

Look! The ashes are still hot, th a fire must have occurred recently. They cannot be very far away.

In the field of ​​socio-political decision-making, the argument by consequences corresponds to the pragmatic argumentation, which transfers the positive or negative evaluation of the effects of a proposed measure to the measure itself.

The pathetic fallacy is a type of pragmatic argument that goes from the premise that « Rain would ruin our party » to the conclusion, « So, it won’t rain”, as if one’s wishes could influence the natural course of events.

2. Arguments by the Identity of the Consequences

The same type of argument applies to deductions made from the implied meaning of words, as an appeal to the sense of semantic coherence or logical consistency:

Topos: “Another topic consists of concluding the identity of precedents from the identity of results.”
Instance: “There is as much impiety in asserting that the gods are born as in saying that they die; for either way the result is that at some time or other they did not exist” (Aristotle, Rhet. II, 23, 1399b5; F. pp. 313-315).

 If the reason for banning marijuana is that it causes a loss of control, then all substances that cause a loss of control must also be banned, including alcohol for example.
If something is condemned because it mechanically involves something negative, then it automatically creates a category of causes “having that kind of negative consequences”, which must also be condemned.

3. Refutation by Contradictory Consequences

Refutation by contradictory consequences is a type of ad hominem, used in dialectic:

Peter says “S is P”.
The fact that S has the consequence Q: the fact is acknowledged by Peter.
However, P and Q are incompatible.
Therefore Peter is saying incompatible things about S.

Example:

Peter says that power is good.
However, everyone agrees that power corrupts.
Corruption is evil.
Since good and evil are incompatible, power should exclude corruption to be good.
Peter says contradictory things.

CONSENSUS

1. Consensus as agreement

See Agreement; Persuasion

2 Argument from consensus

The label argument from consensus, appeal to consensus, covers a family of arguments claiming that a belief is true or that things must be done in such and such a way on the basis that everyone thinks or does so, and that other proposals should be rejected.

We have always thought, wished, done … so; so, buy (please, do…) so.
Everybody loves so-and-so product.
Everybody puts so-and-so ketchup on their burgers!

It implies that by disregarding the existing consensus, the proponent of a new action or a new idea, that is the opponent of the consensus, risks being excluded from that community, see burden of proof.

The universal consensus argument claims that “all people in all times have thought this way things have always been done this way”.
The existence of God has been argued on the basis of the universal consensus argument.

The argument from the relative (partial) consensus includes the argument from majority, the argument from number (Latin ad numerum; numerus, “number”) and related expressions:

The majority / many people … think, wish, do … X.
Three million Syldavians have already adopted it!
My book is selling better than yours.
He is a famous actor.

Common Sense — The argument of consensus is the kind of authority generously granted to traditional wisdom or to common sense, S. Authority.

I know that all true Syldavians agree with this decision
Only the extremes attack me, all people of common sense will agree with me.

The populist argument is based on a real or supposed consensus among (or attributed to) the people, see Ad Populum.

Bandwagon argument and fallacy — The bandwagon argument is a special case of the consensus argument. The bandwagon is the decorated chariot that leads the orchestra through town, the bandwagon argument adds joy and enthusiasm to the dry consensus argument. To get on the bandwagon is to follow the popular movement, to participate in a popular “emotion” in the etymological sense of “a public upheaval”. Joining a party to have fun and sing along should not be condemned as systematically fallacious; but, from the perspective of any opposing party, climbing on the bandwagon can be seen as fallacious, as a follow-the-group or follow-my-leader attitude, sheepish behavior, as uncritically adopting the views of the most vocal or visible group.