Arguments can be approached on the basis of very different systems of rules.

— Rules expressing observational regularities.
— Rules expressing norms, imperatives, which are instrumental for argument evaluation.
— Rules as counsels to do things well, how to convince a person to believe or to do something.

1. General rules of interaction

1.1 Rules of interaction

Argumentative interactions in natural language follow the various systems of rules proposed for interaction in general, so for example, the rule of justification of non-preferred sequences is applied:

A dispreferred second part is a second part of an adjacency pair that consists of a response to the first part that is generally to be avoided, and which is likely to be marked by such features as delays, prefaces and accounts. (SIL, Dispreferred second part)

1.2 Cooperative principle

The principle of cooperation expresses not only what the participants actually do (observational regularity), but also what is reasonable for them to do (rational regularity).

1.3 Principles of politeness

The principles of linguistic politeness regulate talk relationships on the basis of the concepts of face and territory. In ordinary conversation, these rules might inhibit the development of arguments. The overriding concern to preserve the relationship means that contradiction is difficult to express and develop.

1.4 Language Sins

A set of commands related to the control of discourse has been developed by the theological tradition inspired by the Bible. The violation of any of these rules is characterized as a sin of language (Casagrande & Vecchio 1991), S. Fallacies as Sins of the Tongue.

2. Rules specifically attached to argumentative speech

2.1 Rules of the Place

Specific codes are attached to specific argumentative places. Parliamentary rules for example apply in Parliament; tribunal proceedings, or classroom interactions develop in line with their own specific regulatory conventions, S. Forum. These regulations are drawn up in accordance with a sui generis procedure and are applied by the competent authorities ruling in the given place. These rules frame the kind of local rationality which characterizes the “genius loci”, the spirit of the place.

In such places, the rules determine the topics to be dealt with, the procedures that will lead to a legitimate decision and conclusion, and the persons qualified to take the floor; they regulate the right to speak, the quantity of speech, and the succession of turns at speech. These rules might, for example prohibit overlaps and interruptions.

2.2 “The Rules of an Honorable Controversy”

Levi Hedge, in his Elements of Logick (1838), presents the following seven “Rules for Honorable Controversy”:

Rule 1. The terms, in which the question in debate is expressed, and the precise point at issue, should be so clearly defined, that there could be no misunderstanding respecting them.

Rule 2. The parties should mutually consider each other, as standing on a footing of equality in respect to the subject in debate. Each should regard the other as possessing equal talents, knowledge, and desire for truth, with himself; and that it is possible therefore that he may be in the wrong and his adversary in the right.

Rule 3. All expressions which are unmeaning or without effect in regard to the subject in debate should be strictly avoided.

Rule 4. Personal reflections on an adversary should in no instance be indulged.

Rule 5. No one has a right to accuse his adversary of indirect motives.

Rule 6. The consequences of any doctrine are not to be charged on him who maintains it, unless he expressly avows them.

Rule 7. As truth, and not victory, is the professed object of controversy, whatever proofs may be advanced, on either side, should be examined with fairness and candor; and any attempt to ensnare an adversary by the arts of sophistry, or to lessen the force of his reasoning, by wit, caviling, or ridicule, is a violation of the rules of honorable controversy.
(Hedge, 1838, pp. 159-162)

Some of these rules sound familiar. Rule 5 corresponds to the accusation of having a hidden motive: “You agree with this proposal not because you approve it but to please the director”. Rule 6 is original, and refers to the problem of the hidden agenda, or even of conspiracy, S. Pragmatic argument. Disputes can be said to be “honorable” in both the intellectual and social sense. This system reintroduces what is socially acceptable in a situation where the participants will not spontaneously apply the common rules of cooperation and politeness. Such considerations join the rhetorical problematic of the prepon and the aptum (Lausberg [1960], § 1055-1062).

In Hedge’s system, social control is the root of the imposition of co-operation. The rules for avoiding the sins of language originate from religion, S. Fallacies as sins of language. In the Pragma-dialectical system, the system of rules avails itself of communicational rationality, in the spirit of Grice, S. Cooperative principle.

3. Pragma-Dialectic rules and the re-conceptualization of fallacies

These rules define “A Code of Conduct for Reasonable Discussants” (van Eemeren, Grootendorst 2004, p. 190), for partners willing to rationally resolve their difference of opinion. A fallacy is defined as a violation of one of these “Ten Commandments for Reasonable Discussants” (id., 190-196), S. Fallacies (I):

Commandment 1, Freedom rule: Discussants may not prevent each other from advancing standpoints or calling standpoints into question

Commandment 2, Obligation to defend rule: Discussants who advance a standpoint may not refuse to defend this standpoint when requested to do so.

Commandment 3, Standpoint rule: Attacks on standpoints may not bear on a standpoint that has not actually been put forward by the other party.

Commandment 4, Relevance rule: Standpoints may not be defended by non-argumentation or argumentation that is not relevant to the standpoint.

Commandment 5, Unexpressed-premise rule: Discussants may not falsely attribute unexpressed premises to the other party, nor disown responsibility for their own unexpressed premises.

Commandment 6, Starting-point rule: Discussants may not falsely present something as an accepted starting point or falsely deny that something is an accepted starting point.

Commandment 7, Validity rule: Reasoning that in an argumentation is presented as formally conclusive may not be invalid in a logical sense.

Commandment 8, Argument scheme rule: Standpoints may not be regarded as conclusively defended by argumentation that is not presented as based on formally conclusive reasoning if the defense does not take place by means of appropriate argument schemes that are applied correctly.

Commandment 9, Concluding rule: Inconclusive defenses of standpoints may not lead to maintaining these standpoints, and conclusive defenses of standpoints may not lead to maintaining expressions of doubt concerning these standpoints.

Commandment 10, Language use rule: Discussants may not use any formulations that are insufficiently clear or confusingly ambiguous, and they may not deliberately misinterpret the other party’s formulations.

This system is inspired by the proposals of the Erlangen school for the definition of a rational “ortholanguage”, S. Logics for dialogue. In the spirit of Grice, these commandments introduce or impose cooperation where it would not be spontaneously practiced by the participants. The game is based on the notion of standpoint. It corresponds to a dialectical treatment of the difference of point of view, with a proponent affirming the point of view and responding to the attacks of an opponent who casts doubt upon it. Rule 9 recalls the aim of the game, that being to settle the difference of opinion either by eliminating the unsustainable opinion or by eliminating the doubt about a well-justified opinion.

Such a system of rules accounts for the validity judgments of the speakers (van Eemeren, Garssen, Meuffels 2009). It is also possible to identify the implicit rules to which the speakers refer for their evaluations based on observing their practices (Doury 2003, 2006).