ISSA Proceedings 1998 – Reasonableness Rather Than Rationality

ISSAlogo1998The idea that logic alone can determine the distinction between good and bad arguments is rapidly being replaced by a broader dialectical theory of argumentation. Yet, to preserve a suitable notion of normativity, dialecticians appeal to a notion of rationality that shows much the same features as the disreputed logic is sought to replace. In this contribution, I will diagnose the problem and present an alternative: dialogical rhetoric.
The idea that bad arguments are logically interesting is rather young. For ages, logic was primarily interested in good arguments. Bad ones were negatively defined as not-good, and, as distinguishing instrument, logic could be limited to answering the question what accounts for the goodness of arguments. Modern formal logic, in this fashion, sought after sound arguments that yield conclusions by necessity. Starting with true premises, a truth-preserving method of valid inference warrants conclusions that cannot be wrong. The truth of the premises, although essential for soundness, is left to the relevant fields of investigation. Logic proper concerns the method of inference and deals only with validity. Logically speaking, a good argument is a valid one, and a bad argument is invalid. This type of logic observes what we may call the deductive demand. A good argument is one of which the conclusion follows necessarily, under the condition that its premises are true.
Hamblin’s Fallacies (1970) cracked the ice. He showed that the notion of invalidity was not adequate in accounting for bad arguments, and that consequently the deductive demand did not serve the distinction between good and bad arguments. In a nutshell: invalidity was neither a sufficient nor a necessary condition for fallaciousness. Some fallacies are not invalid at all (e.g. the notorious begging the question), and many arguments are invalid but not fallacious (all inductive arguments are deductively invalid). Many thinkers have followed Hamblin, and added doubts on the suitability of the deductive demand. I will mention three problems in particular.

1. The deductive demand is an all-or-nothing matter: only necessary conclusions are allowed and anything less is rejected. To every problem there is only one solution: the best one. Curiously enough, however, no account can be given for a notion of `better’. This makes argumentation, in any substantial sense, impossible. Argumentation, after all, consists of arguments pro and arguments contra, and the balance of those two factors constitute the strength of an argument. The deductive account cannot acknowledge positive and negative forces in this way because a deductive argument `knocks down’ either way.

2. The deductive demand cannot acknowledge alternatives, and is in that sense monological. The point is that as a truth-preserving method it should yield necessary conclusions and it cannot allow a different logic arriving somewhere else. But if so, any deviation of the monologic is impossible, including unlogicality. Indeed, as the early Wittgenstein said: `we can think nothing unlogical, since if we could, we would have to think unlogically’(Tractatus: 3.03). The idea is that thinking as such presupposes logic. This feature gives monologic a transcendental flavor: it provides for the very condition of the possiblity for thinking and cannot be questioned, nor sustained by argumentation. Monologic must be `seen’, and can only be `shown’. The problem, obviously, is that bad arguments do exist and that we must presume that the persons who advance them in fact thought badly.

3. Perhaps the most serious problem for the deductive demand is that it is not hard at all to meet it. Many arguments are sloppy in the sense that not all premises are explicitly mentioned. This is not a problem, because most people will tacitly add the missing premise. To determine the deductive validity, however, we must add the hidden premise. This can do no harm because it cannot make a valid argument invalid, but it can do much good by explicitizing an implicit premise. The problem, however, is that any argument can be made valid by adding the right premise. The associated conditional, or even the conclusion itself, and perhaps even the negation of one of the other premises[i], will do. This simply means that either an argument is valid, or can be made valid. Deductively, no bad arguments exist. Deductive logic, far from providing a suitable instrument, has no powers to perform its distinguishing task.

Dialectical Shift
Increasing numbers of logicians have dropped the deductive demand over the last three decades, in favour of a dialectical approach. Dialectics differs from deductive logic by applying acceptable instead of true premises, and by acknowledging different systems of logic between which a choice must be made. Dialectics  does not yield necessity but is satisfied with probable conclusions[ii]. Dialectical logic is much more modest than deductive logic, and `may or may not be a good one in the full alethic sense’, as Hamblin says, `but it is certainly a good one in some other sense which is much more germane to the practical application of logical principles’(Hamblin 1970: 241).
If logic is to perform its normative task in the practice of argumentation, it should comply to the nature of argumentation better than formal deductive logic does. A first observation is that argumentation is always a dialogical matter involving, basically, two participants: a proponent, defending a thesis, and an opponent, resisting the thesis. Monologic concentrated on the support of the conlusion only, but dialectical logic emphasizes the generic role of the opponent: only when disputed it makes sense to defend a thesis. Supporting an undisputed thesis is a waste of time at best; irrelevant babbling at worst; or an ignoratio elenchi in between. Dialectical logic, thus, takes disagreement as a condition for the possibility of discussions, but this calls for a suitable form of regimentation. Or else, the participants may `simply bash each other until bashing served no further purpose’(Freeman 1991: 18).
There are many different ways to deal with disagreements. We may try to solve the conflict, or stick to investigating where exactly the difference lies. We may want to settle the issue by means of force, or try to tackle the opponent by ridiculizing her position. Different ways of dealing with conflicts yield different types of discussion. And different types allow for different moves. What is suitable in a quarrel is not always acceptable in a critical discussion, and vice versa[iii]. Whether or not a move is acceptable depends upon the type of discussion that is going on. Dialectical logic presumes that it is up to the participants to decide upon how they want to deal with their disagreement. But when they have agreed upon a specific type of discussion, they should observe its particular regulative rules. The goodness of an argumentative move is determined by the rules that are in force: compliance with the rules makes an argument good whereas violation of the rules disqualifies it.
Clearly, the participants must voluntarily submit to the rules and their compliance to some type of discussion must be of their own accord. Only when someone has accepted the authority of a set of rules, she can be held committed to them. Dialectical rules are only in force if they are conventionally accepted by all participants involved. The rules can change only when the conventional demands are being observed: suspend the discussion in progress, discuss the necessity of accepting new or modified rules, authorize them conventionally, and recommence the discussion proper again. The conventional authorisation of the rules implies that dialectical system is always local in scope; only when conventionally authorized, influences from other discussions can be acknowledged. Very often, the conventional aspect remains implicit: many rules of discussion go without explicitly mentioning them and it would be even very tedious to issue a `dated and signed written declaration’ every time an argument were about to begin[iv]. Nevertheless, as Douglas Walton says, `the rules can be explicitly stated, and agreed to by the participants, where it is useful and necessary, at the opening stage’(Walton, 1989, 10, italics whs). In other words, the participants would accept the rules if they were explicitly asked to. Conventional normativity may be called `would-normativity’.

The normative force of rules provides for a possibility to determine win or loss of a discussion in an objective way. If the rules are clear, anybody can see whether they are being followed or not. In particualr, it allows the logician to put a decisive verdict on discussions. She is supposed to be able to determine exactly what type of discussion is going on, and she is supposed to be able to apply the suitable standard to the discussion and determine who has the best arguments. Because the participants have committed themselves to the rules, and she is only applying these standards, her verdict is normative for the participants involved. Obviously, the external observer must be neutral regarding the positions of the participants. His verdict should be unbiased and only the arguments as advanced should count. An external observer can control the agreed-upon regimentation of the discussion, and by application of that standard determine win and loss in an unbiased way. Barth and Krabbe define rationality in these terms: `it is not irrational to lose a discussion’. But it is – we suggest – irrational not to admit that one has lost’(Barth and Krabbe 1982: 71).

Would-normativity is not satisfactory, because, shortly, it allows for would-not. In face of losing a discussion, a participants may simply withdraw his commitment, or demand modification, or simply deny that he made the commitment at all[v]. The external observer can note this, but has nothing to go on to condemn it. The evil-doer can simply claim not to accept the move in question. The local character of dialectical normativity, demanding specific agreement, allows for very limited, even opportunistic exceptions. Would-normativity is not what we expect from normativity; it lacks normative force precisely where it is needed most: when somebody would not accept something she should accept. To account for should-normativity, we must rule out arbitrary or strategical one-sided withdrawals. Dialectically, this is only possible if the agreements are controlled in some way. Not only the observance of agreed-upon rules, but also the agreement as such must be secured to safeguard normativity. If this were not regimented conventional normativity were a farce, because participants could change their commitments at will.
Control of agreements as such is needed for another reason as well. How are the conventional agreements arrived at? Presumably by discussion. But in what way is such a meta-discussion regulated? If a conventional set of rules were normative here as well, an infinite progress would have started. Dialectical logicians, if they address the problem at all, appeal to a notion of `logical intuition’ or `natural rules’ of normal argumentative behavior[vi]. The idea is that participants want to cooperate because they agree on the purpose of the discussion. If so, it is rational to follow rules that promote cooperation, for example: do not abuse the adversary; acknowledge loss if forced to; do not mislead the other; etc. Although the rules that make up for dialectical rationality are innocent enough, they are substantial. They do not only demand that one must be reasonable, they also say what counts as reasonable. Rationality, thus, provides for a substantial higher-order standard, which stops higher-order discussions in a notion of rational acceptability. We may see, incidentally, that a reason is given to be rational: it promotes the purpose of the discussion.
Still, if conventional acceptance is to be taken serious we must acknowledge that someone may reject rationality in terms of normal argumentative behavior. For example, what if compliance to the `normal’ rules would result in loss of the discussion, and the stakes are just too high for that? We need not necessarily think of people seeking advantage to find examples. Gandhi should be called irrational if `normal’ argumentative behavior defined the substance of rationality. But if there can be reasons for being irrational, can those reasons be good? And what standards are conceivable to determine this? Ever higher-order systems of rules lead to the infinite progress. Only an indisputable rationality can call such progress to a halt.

The Rational Observer
It may seem, and it is often claimed, that the dialectical shift in logic followed Hamblin’s proposal to leave `the control of each discussion’  in the hands of the participants themselves’(Hamblin 1970, 283). But the foregoing suggests a third crucial role: the external observer who controls the rationality of the discussion. Dialectical logic is not dialogical, but in fact trialogical, and the logician typically is in the position to play the third role. The dialectical understanding of normativity as being dependent upon agreement is responsible for this proliferation of logical roles. To account for agreement we must account for commensurablity: the standards of assessment must be the same for everyone involved. If normativity is a matter of agreement, it should transcend the particular preferences and provide for a standard that commensurates the idiosyncratic “standards” of the respective participants[vii]. The rational observer is the embodiment of this standard[viii]. This means, however, that the control of the discussion is in the hands of the participants themselves only in so far as they represent the verdict of the rational observer.
It may not surprise us, considering the role of the rationality, that dialecticians generally make a qualitative distinction between two different ways of dealing with conflicts; they distinguish between settling and resolving a dispute. Settling simply indicates that the problem at issue is set aside by whatever means: tossing; refereeing; fighting or intimidation. `To really resolve a dispute’, however, `the points that are being disputed have to be made the issue of a critical discussion that is aimed at reaching agreement
’(Van Eemeren and Grootendorst 1992: 34). Although people are granted the freedom to deal with conflicts of opinion in several different ways, one specific type of discussion if singled out: the prototype of rational argumentation, critical discussion.

The rational observer is unbiased and evaluates any discussion by the strength of the arguments alone; not by the particular interests of the participants. The criteria applied by the rational observer depend upon the type of discussion that is going on. Still, contrary to what dialecticians tend to say, the participants are not free to chose any type of discussion they want. The choice of a type of discussion depends upon the best way to deal with a problem, and the rational observer surveys all possible ways and can pick the best one. The notion of rationality, indeed, is only useful if it provides for a `best’ solution. If it yielded just another opinion, it could not be normative regarding the other options. It would just be another perspective like those of the other participants. The opinion of the rational observer must be qualitiatively better to have normative force. In fact: it must be the best solution, because rationality should be normative for all possible positions. But this merely means that rationality has taken over the role monologic played before the dialectical turn. To account for its normativity, dialectics turns out to be a monologic in disguise. If so, we may ask to what extent the objections to monologic apply to dialectical rationality as well? To a large extent, I think.

1. Dialectical rationality is supposed to settle issues and cannot itself acknowledge alternatives. If the ideal standard were applied in any pure form, everybody would agree to its conclusions. This regards the outcome of any discussion that is regimented by a specific set of rules, but it also applies to the higher-order choice of a logical system as such. The ideal observer makes the ideal choice of a logical system. For every problem, an ideal rationality would find (or invent if necessary) a perfect normative tool to solve it. In this way, rationality does not acknowledge `better’ anymore than monologic and quests for the `best’ solution as well.

2. The acknowledgement that people in fact argue and that arguments pro and contra both cut ice is a matter of discomfiture and is a result of the fact that real-life arguers are not perfectly rational. The problem is how this imperfection as such can be accounted for. As highest standard, rationality has a similar transcendental status as monologic: `we ”play” upon modes of thought we expect the readers already to follow’(Barth and Krabbe 1982: 75). In what way can people be irrational, under these circumstances. Indeed, how can they have a perspective that deviates from the rational one?

3. The main problem for a dialectical notion of rationality is that it is an ideal standard and, as human beings, we have only our limited perspectives at our disposal. The normative standard of an ideal observer is fundamentally inaccessible for us. In argumentation both parties may claim that their own arguments accord to the rational standard, but that is often precisely what is at issue. When it comes to distinguishing good from bad arguments, we need an instrument that is available, and dialectical rationality by definition is not.

The failure of a dialectical notion of rationality to perform its normative function can be illustrated by making a short detour to fallacy-theory. Van Eemeren and Grootendorst link fallacies directly to the violation of specific rules for critical discussions: `the dialectical rules which are violated in case of fallacies are applicable only in so far as the purpose of the discussion is to resolve a dispute’(Van Eemeren and Grootendorst 1987: 296, italics whs). The pragma-dialectical understanding of rational normativity, thus, is conditional: if people engage in a critical discussion, they must obey its specific rules. But the occurance of a fallacy simply yields a modus tollens of the normative conditional: violating the rules simply negates the consequent which means that the antecedent is false as well. The occurance of a fallacy, unless as slip of the tongue or corrigeable mistake, simply indicates that no critical discussion is going on. If so, as Van Eemeren and Grootendorst argue, it is not possible to apply the standard for a critical discussion and consequently `there is no point, from a dialectical perspective, in referring to a fallacy’(Van Eemeren and Grootendorst 1987: 298). Dialectical normativity based on rationality fails to perform its normative task.
In brief: dialectical normativity is either a monologic in disguise, meeting much the same problems as deductive monologic, or the rational solution cannot be distinguished qualitatively from other opinions and represents just another point of view without specific normative force. Slightly differently put: the verdict of the neutral external observer either remains external and thus irrelevant for the participants, or becomes an element within the discussion, cancelling its neutrality. The external rational observer will not do for a suitable notion of normativity. Yet, we need not be sad about this. It may, as Hamblin argued, `not be the logician’s particular job to declare the truth of any statement, or the validity of any argument’ (Hamblin 1970: 244).

Dialogical Rhetoric
Rhetoric is often blamed for lacking normativity. It is conceived of containing argumentative tricks that induce people to accept things they would not have accepted were they put in less woolly terms. Rhetoric aims at bringing people to accept conclusions they would not accept by themselves and should not accept by general standards.
Rhetoric is considered an instrument to deceive people. Such an understanding of rhetoric is very far off the mark, at least when we look at rhetorical theories. Classical rhetoricians maintained that only the virtuous could speak well and that deception was the least advisable strategy for any orator. We need not appeal to a now outdated Aristotelean epistemology, -which linked virtue and truth-, to see that deception is a very bad advice for a speaker. Trustworthiness pays double; deception only makes people suspicious on the long run. Only a very shortsighted rhetoric resorts to deception. Rhetoric does not focus on the advantages of the speaker, but much more on the position of the hearer. Rhetoric, Perelman and Olbrechts-Tyteca say, `aims at gaining the adherence of minds’(Perelman and Olbrechts-Tyteca 1969: 14), and this can only be achieved if, indeed, the audience to which the speaker directs her arguments becomes convinced. The speaker seeks the cooperation of her audience and in order to attain it, she must take seriously the standards of the hearers. This rhetorical demand for a fundamental audience-orientation implies the pedestrian hint to speak English to anglophones and not to bore lay-people with technicalities. But it also takes into regard the asymmetrical startingpoint of discussions. Rhetoric accepts the idea of dialectics that some thesis must be disputed for an argument to begin. That is, only when a thesis is being questioned by someone, it makes sense to support it. As it is the actual resistance of a specific opponent that blocks the establishment of the thesis, it is his doubt that should be removed. The very raison d’etre of argumentation indicates that a specific audience is addressed.
But if rhetoric directs its arguments at a particular audience what about the rest of the world? Perelman and Olbrechts-Tyteca discuss mixed audiences in this respect, and they propose a notion of the Universal Audience to conceive of arguments that are convincing for all audiences, and thus normative for any audience. This construction is superfluous, however. The speaker can only orient herself to the audience as she perceives of it. She has no direct access to the minds of her hearers and can only estimate its standards. Particular, mixed and universal audiences are all projections of the speaker, and the orientation to the audience thus has always a tentative character that needs to be adjusted while the dsicussion is in progress. Perelman and Olbrechts-Tytcea define the  notion of audience as `the ensemble of those whom the speaker wishes to influence by his argumentation’(Perelman and Olbrechts-Tyteca 1969: 19), and this can be substantiated in a particular, mixed, or perhaps even universal way. There is no need to make a fundamental or even qualitative distinction between types of audiences [ix].
Still, there is an important normative problem. The demand to orient oneself to the standards of the audience, erodes the position of the speaker herself! If the standard of the audiences were all that counted, the speaker seems to be extradited to the whims of her audience. This surely, would be a very disturbing consequence of audience-orientation. There would be a moral objection: it is absurd to demand the orientation to abject standards. There is a rhetorical objection on the longer run: one would disqualify as serious partner in discussion when shifting standards according to specific audiences.
Most serious, however, is the logical objection that only by observing one’s own standards a thesis is worth defending. Much like the dialectical idea that an argument only begins when some thesis is being questioned, we should say that an argument only starts when the speaker is willing to support it. If only the standards of the audience were decisive, its very resistance would be the end of the discussion. Precisely because the speaker is committed to the thesis, she defends it, but this is only possible if she acknowledges the normative force of her own position, at least for herself.
If rationality fails to transcend the subjectivity of the respective participants, it seems that the disagreement that initiated the discussion in the first place pervades the entire discussion and that, indeed, we have nothing to go on but the idiosyncracies of the respective participants. In contrast to dialectics, however, I do not think this is much of a problem. In fact, I think that acknowledging the fundamental differences between participants may even yield a much stronger notion than the dialectic appeal to rationality. Note that agreement is not denied. People may, and in fact do, agree on many things; just as they are disagreeing on many other things as well. My point, however, is that agreement is insubstantial for normativity, and that commensurability is of no consequence when it comes to distinguishing good from bad arguments.

Whereas dialectics stopped the infinite progress jeopardizing conventionalism in the rational acceptability of arguments, I propose to locate the stop of the progress in the actual acceptance by the adversary. Instead of tacitly assuming a third logical role in the dialogue, I suggest we take the responsibility of the participants themselves seriously. The idiosyncracy of the standards is not resolved in the commensurability of a transcendent standard of rationality, but is restrained by eachother. When rhetoric is seen from a dialogical perspective, we will observe that the orientation to the audience goes both ways. In any dialogue, of course, both participants are speaking, and both must orient themselves to the standards of their respective audiences, that is: their adversary. A dialogical rhetoric, I suggest, understands a discussion as the mutual orientation of the participants to each other’s standards. Not only actively, as proponent, but also passively, as opponent, a participant must orient herself to the other. Dialectical logic burdens only the proponent to proof her thesis. The opponent can ask any question he likes. Dialogical rhetoric concedes this in principle, but adds the condition that the questions must be reasonable. The point simply is that not every question is good enough to demand a serious answer. As Aristotle remarked: `a man should not enter into discussion with everybody or practice dialectics with the first comer’(Topica, VIII, 14, 164b). The proponent may ask the oponent to defend his opposition. In effect this means that both participants face burden of proof for their respective positions both in defending and in resisting a thesis.

Both participants are both advancing a position of their own, and opposing the position of the other. Whether they succeed in doing so is up to the respective adversary. It is the adversary that has to be convinced of the reasonableness of the advanced move, and it is the adversary’s standard that determines the goodness of the argument. But only so, we should add, if the adversary is reasonable himself. He may for various reasons resist the thesis, even against his better judgment; he may use fallacies to distract attention; he may simply be too ignorant to see the real point… He may simply be the wrong person to discuss the issue with. He may not be among those whose minds we seek adherence of. The reasonableness of the hearer opposing some thesis, depends on the standards of the proponent.
The basic idea of dialogical rhetoric is that the two personal or even idiosyncratic standards of proponent and opponent `span’ a normative field that determines the argumentative moving space of a particular discussion. Like dialectical discussions, such a dialogico-rhetorical normative field always has only a local character, because it is always the result of the contributions of the particular participants involved. Yet, we may see that discussion has consequences for other discussions. The audience is, as said, a construction of the speaker, and she can only make her projections on the basis of past experiences or reputation of the adversary. A reputation may seriously damage, or strengthen, one’s point of departure in other discussions. Bad behavior may have as a consequence that the adversary terminates the discussion at issue, but may also deter other potential partners in discussion. Still, sometimes it may be worth the risk.
The adversary determines whether or not an argumentative move is accepted or not. If it is, the move is established. If it is not, the proponent may try to support the claim in an other way, or she may question the reasonableness of the resistance. If so, it is up to the opponent to defend the opposition. In general, this will not be a fruitful strategy when a discussion has just started. A discussion begins with resistance of the opponent and the proponent’s wish to convince him. It is strategically unwise to begin a defense by asking why on earth he is resisting her claim. But at the end of a discussion, after many moves have been made, such a question may not be strange at all. If an elaborate defence has been given it may very well be the question why somebody is still resisting the claim that has been supported extensively. Still, resistence may be the right thing to do; the opponent may convince the proponent of the reasonability of the opposition. This may result in the withdrawel of the claim, in which case the opposition of the claim is established[x].

The normative force of dialogical rhetoric lies in the fact that for the establishing of any move both participants are responsible. Obviously, the proponent is responsible for the moves she advances. But the opponent also becomes committed when he does not, or no longer, resist the claim[xi]. In this way, both participants become responsible for both supporting and rebutting moves. Both positive and negative aspect form, as it were, a vector that together constitute the strength of the argument. The resulting conclusion is binding for both participants because they either advanced or accepted the consititutive elements.
Dialogical rhetoric plays on the disagreement that got the argument started in the first place. It works in cases of incommensurability, but can obviously also be maintained when the situation is much less différant as some contemprorary philosophers want us to believe. The matter is insubstantial for a suitable notion of normativity. Just as unimportant is the taxonomy of types of discussion. Discussions are not neatly defined from the outset and may slide from one type to another[xii]. The problem is that if the rules are normative, it is impossible to see how such a sliding could ever occur. In fact, a rule-based normativity should prevent normative sliding. If incidental exceptions to the rules are allowed this merely means that the normativity is not located before the argumentation proper starts, but within the discussion itself. Even if rules were laid down at the beginning, the very decision that no exception is to be made puts the normative authority within the discussion proper. But this is simply to say that it all depends upon whether or not some argumentative move is accepted or not. There is no use in doubling this issue by postulating incidental rules in between. There is no use for any notion of discussion-rules other than as suggestions of strategic hints, indicating argumentative regularities that may be helpful, and even to the benefit of everybody involved. The point is that an argument does not become good or bad because of these rules. They do so because they are, or are not, accepted by the only one whose opinion is of any substantial interest: the adversary’s. Instead of the term `rules’ I prefer the rhetorical term `topos’. The question is not how to authorize a rule, but how to implement a topos effectively.
The goodness of arguments is determinied by the acceptance of the adversary; the badness of arguments by the refusal of the adversary to accept an argumentative move. This idea has consequences for the notion of fallacy. Without an operative notion of discussion-rules, fallacies cannot be seen as violations of rules. The traditional fallacies can, however, be understood as unadvisable argumentative strategies. Arguments that are usually considered fallacious are bad because they are weak; they are easy to expose, and not very convincing for the most part. A taxonomy of fallacies is useful to show risky argumentative strategies, but not as a list of arguments that are as such always bad. If only, I may shortly point out, because fallacies are not merely slips of tongues, but are often committed for good reasons. A fallacy can shift the burden of proof to the adversary because his charge of `fallacy!’ may be called for support. In this way, committing a fallacy can be strategically advantageous. Fallacies should not only be studied for logical self-defense, but also as a means to win a discussion. If an adversary accepts a `fallacy’ there is not much reason to call it a fallacy at all, although the logician may want to point out to the naive adversary that he could have maintained his position better. A fallacy is only fallacious if it is exposed as such, and not all traditional fallacies are fallacious all the time. In any way, it is up to the adversary to point out the fallacy, not to any external observer. But a charge of `fallacy!’ can always be called for defence.

Postlude
Obviously, despite overpowering evidence and even while acknowledging the reasonableness of the arguments, someone may persist in resisting a conclusion. No account of normativity can prevent this, but at least dialogical rhetoric can blame someone for doing this. Dialectical logic, depending on the voluntary submission to rules of discussion can only determine the fact that someone does not accept the rules that were supposed to be normative. It can never blame someone for not voluntarily submitting to any rule. Not even to rules of transcendental rationality: there is no dialectical answer to someone who wants to be irrational. But there is a rhetorical answer to someone who wants to be unreasonable: go and waste someone else’s time. It moreover allows one to take up responsibility for one’s own position, even facing non-cooperation because of unreasonable demands of the adversary.

NOTES
i. Obviously, this will make the premises inconsistent. But the problem of inconsistency is its triviality, not its invalidity. After all: ex falsum sequitur quodlibe.
ii. Cf. Van Eemeren, Grootendorst, and Snoeck Henkemans 1996, chapter 2.
iii. Walton distinguishes between eight different types of discussion, including eristic discussions. Most dialecticians, however, do not recognize the latter as genuine discussion. Cf. Walton 1989: 3-11.
iv. Cf. Barth and Krabbe 1982: 21f, defining a logical convention for a well-defined company.
v. Walton and Krabbe see retraction as ‘one of the most fundamental (almost intractable) problems concerning commitment’. They are certainly right, but the problem may be less intractable if there were no need for an external observer to decide upon the acceptability. Cf. Walton and Krabbe 1995: 9ff.
vi. Cf. e.g. Barth and Krabbe 1982: 39; 75.
vii. Johnson and Blair argue that: ‘many people evaluate arguments by one ‘standard’ only: does it support my view or not? That’, they insist, ‘is not a logical standard of evaluation but rather a purely idiosyncratic one’(Johnson and Blair 1983: 30).
viii. Obviously, the rational observer is a logical role; it is not demanded that it is actually present at the spot. The participants may themselves take up the role of the rational judge. What is important, however, is that only an unbiased evaluation of the advanced arguments is normative.
ix. Cf. also Ray 1978.
x. It is also possible that the participants accept the reasonableness of each other’s position and yet retain to their own point of view. The conclusion is that the disagreement is not resolved.
xi. At what stage he does so is not important at this point. In some cases, hem must be quick to react, because the discussion may pass an irreversible moment after which no return to an earlier stage is possible. In other cases, steps may be retraced to an earlier stage. What is allowed is simply ot the adversary to decide.
xii. Cf. Walton and Krabbe 1995: 100-116.

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