ISSA Proceedings 2002 – Persuasive Success And Normatively-Desirable Argumentative Conduct: Is It (Persuasively) Bad To Be (Normatively) Good?

logo  2002-1One recurring concern in argumentation studies is the interplay of descriptive and normative approaches to argument. For example, van Eemeren, Grootendorst, Jackson, and Jacobs (1993) have discussed problems encountered in using normative models to describe natural argumentative discourse. This paper addresses a different but related aspect of the relationship of descriptive and normative concerns, by comparing the results of studies of factors influencing persuasive effectiveness (that is, research findings indicating what makes for persuasive success) against conceptions of normatively-desirable argumentative practice (particularly as suggested by the pragma-dialectical approach). The general question is that of the potential tension between practical persuasive success and normative directives about argumentative conduct. The nature and extent of such tension is an empirical question, and hence this paper closely inspects existing persuasion research to see what light might be shed on whether (and the degree to which) persuaders face a choice between being normatively sound or practically persuasive.

1. Preliminaries
Three preliminary observations are appropriate concerning some uncertainties attendant to this undertaking.
First: There is no single detailed normative argumentation framework that enjoys thoroughgoing acceptance, and hence there is no easily-identifiable set of obvious specific normative standards to employ in this sort of undertaking. In what follows I will often refer to elements of the pragma-dialectical approach (van Eemeren & Grootendorst, 1984), because I think its focus on arguer conduct is especially congenial to the task at hand; but my hope is the relevant pragma-dialectical elements can be seen to be realizations of broader normative principles likely to enjoy widespread endorsement.
Second: Claims about the influence of various factors on persuasive effectiveness necessarily carry with them all sorts of caveats about the evidence underwriting such claims (both general caveats and ones specific to the particular research reviewed). This paper has not been burdened with all the hedging that might have been given. But–by way of reassurance–I do think that the empirical generalizations invoked here are sufficiently secure to permit us to consider their relationship to normative argumentative standards.
Third: Persuasion researchers have commonly not set out with the explicit aim of seeing the persuasive effects of variations in normatively-desirable argumentative conduct. That is to say, there is necessarily some imperfect articulation here, because the research evidence has been gathered with different purposes in mind. Even so, it turns out that various lines of persuasion research do speak to the question of the persuasive effects associated with various normative directives.

2. Normative requirements and persuasive effects
This analysis is organized by four broad requirements for normatively-sound argumentative conduct: that arguers make clear what overall claim is being advanced, that they specify their support for that overall claim, that they defend their views against objections, and that (broadly) they pay close attention to arguments.

2.1 Articulation of conclusion
One general requirement for normatively-sound argumentation is that an arguer make clear just what overall claim is being advanced. In van Eemeren and Grootendorst’s (1992) simplified (nontechnical) presentation of the pragma-dialectical rules for critical discussion, this idea is at least partly represented by a portion of rule 10: “A party must not use formulations that are insufficiently clear or confusingly ambiguous” (van Eemeren & Grootendorst, 1992, 209). Any sort of vagueness or ambiguity thus is potentially normatively questionable: “Evasion, concealment, and artful dodging… are and should be excluded from an ideal model of critical discussion” (van Eemeren et al., 1993, 173). And of all the argumentative elements that might want clarity, surely none is more crucial than the advocate’s overall claim.
Of course, arguers might think that explicit articulation of their overall advocated position (the arguer’s overall conclusion, recommendation, standpoint) can somehow undercut persuasive success. For instance, it might be feared that an explicit statement of the desired overall conclusion could be insulting to the audience (because it states the obvious), or might seem too aggressive or insistent; or it might be thought that leaving the overall conclusion unstated would enhance persuasive effectiveness because it invites the audience’s participation (in an enthymematic way). Hence even though an advocate’s argumentation contains appropriate materials to support the advocate’s overall conclusion, an advocate might nevertheless opt for coyness, thinking that however normatively questionable such coyness might be, it will perhaps enhance persuasion.

A number of experimental studies bear on this possibility. The most relevant studies are ones that compare the persuasiveness of two messages varying specifically in whether the message contains an explicit statement of the advocate’s overall conclusion. For example, Struckman-Johnson and Struckman-Johnson’s (1996) research compared AIDS public service announcements with and without an explicit recommendation to use condoms.
A systematic meta-analytic review of such studies has been reported by O’Keefe (in press; see O’Keefe, 1997, for an earlier review). Meta-analysis has become the preferred means of research synthesis in research domains such as this. In contrast to traditional narrative reviews that focus on whether individual studies achieved statistically significant effects, meta-analytic reviews focus on the size of the effects obtained in individual studies, on whether the overall average effect is dependable, and on the identification of variables that might influence the size or direction of any observed effect.
Across the 17 studies identified as relevant in O’Keefe’s (in press) review, a dependable overall effect (corresponding to a correlation of about .10) was observed, such that messages containing an explicit statement of the advocate’s overall conclusion were significantly more persuasive than parallel messages omitting such a statement. Moreover, there was no evidence that this effect was influenced by such factors as the audience’s intellectual capabilities (e.g., explicit conclusions appeared to enjoy the same advantage among less-educated receivers as among better-educated receivers) or the audience’s initial position (that is, explicit conclusions appeared to enjoy the same advantage when receivers initially favored the advocate’s view as when receivers opposed it). O’Keefe (in press) discusses several explanations for these results, but here the point of interest is simply the overall effect itself: Advocates did not profit persuasively–and in fact damaged their persuasiveness–when they adopted the normatively-questionable tactic of avoiding an explicit statement of their overall standpoint. That is to say, with respect to this particular element of normatively-desirable argumentative practice, there is no contrast between being normatively good and being practically effective.

A related set of studies (also reviewed by O’Keefe, 1997, in press) also speaks to the question of the persuasive effects of variation in how advocates render their overall conclusion. In these studies, the advocate states the conclusion explicitly but varies the degree of detail or specificity in the rendition of the conclusion. For example, Evans, Rozelle, Lasater, Dembroski, and Allen (1970) compared messages giving relatively general, unelaborated dental-care recommendations with messages giving more detailed, specific recommendations. Thus in these studies, the experimental contrast is not between messages that contain an explicit conclusion and ones that omit such a conclusion, but rather between relatively more or less specific renditions of the overall conclusion.
Across the 18 studies identified as relevant in O’Keefe’s (in press) review, a dependable overall effect (corresponding to a correlation of about .10) was observed, such that messages containing a more specific statement of the advocate’s overall conclusion were significantly more persuasive than parallel messages with less detailed conclusions. That is to say, paralleling the effects observed for including or omitting explicit conclusions, advocates profited persuasively when they provided (the presumably normatively-desirable) greater specificity concerning their overall recommended views. Thus, again, with respect to this particular element of normatively-desirable argumentative practice, there is no contrast between being normatively good and being practically effective.
Taken together, then, these two lines of research suggest that an advocate’s lack of explicitness about the advocate’s overall standpoint–whether through omitting a statement of the overall conclusion or through stating the conclusion in a global (general) rather than specific fashion–impairs persuasive success. That is to say, the normatively-sound argumentative practice of explicitly articulating the advocate’s conclusion will, if anything, commonly enhance persuasive effectiveness.

2.2 Articulation of support
A second broad requirement for normatively-sound argumentative practice is that arguers spell out (or be willing to spell out) their arguments in support of the overall claim being advanced. In the simplified (nontechnical) presentation of the pragma-dialectical rules for critical discussion, this idea is at least partly represented by the general “obligation to defend” represented in rule 2: “A party that advances a standpoint is obliged to defend it if asked by the other party to do so” (van Eemeren et al., 1996, 283; see also van Eemeren & Grootendorst, 1992, 208). The conjunction of an obligation to defend one’s claim and an obligation to (be willing to) maximize explicitness naturally produces a generalized normative imperative to be willing to make one’s supporting arguments explicit.
Notice that the appropriate (realistic) normative requirement is not that every argument be made in a completely explicit form (in which every premise and sub-premise is expressed), but rather that arguers be capable of making explicit their underlying reasoning. Of course, the best evidence of such capability is actual explicitness, and hence arguers who provide a more explicit rendition of their argumentation may be said to more straightforwardly represent adherence to this normative ideal.
But arguers might fear that adhering to this normative ideal could impair practical persuasive success. The more explicit one’s supporting arguments are, the more opportunities there are for listeners to find defects. Detailed articulation of an advocate’s supporting materials naturally invites closer scrutiny, counterargument, and rejection. Such explicitness can be said to enlarge the “disagreement space,” in the sense that it puts more claims on the table for discussion – claims to which objections might be raised (for discussion of the idea of disagreement space, see van Eemeren et al., 1993, esp. 95-96; Jackson & Jacobs, 1980).

The empirical evidence that bears on this matter is limited, in that sense that it has taken up only a few of the various ways in which supporting argumentation might be made more explicit. But two particular forms of variation in support explicitness have been studied relatively extensively. The first is variation in whether the advocate explicitly identifies the source(s) of information and opinion that are offered in the message. For example, Cathcart’s (1955) research included a comparison between one message in which “all contentions and assertions in the speech were directly supported with evidence, but none of the evidence was linked to a source or documented in any way” and a second message with the same evidence but also with accompanying information about the source (“the name of the person or document quoted and the place and date of its promulgation”; Cathcart, 1955, 228-229).
O’Keefe (1998) reported a meta-analytic review of 13 such studies. Across these studies, a dependable difference (corresponding to a correlation of about .07) was observed such that messages providing citations to information sources were more persuasive than their less explicit counterparts. As noted in that review, these studies typically used what would be likely be perceived to be relatively high-quality information sources – which means one cannot be sure that the same effect would obtain were lower-quality sources to be cited. (Little research exists on the question of the effects of citing lower-quality sources – and the extant studies have not produced consistent results; see Cronin, 1972, and Luchok & McCroskey, 1978.) But the evidence in hand does indicate that the normatively-desirable practice of identifying information sources will at least sometimes enhance persuasive effectiveness.
The second form of variation in support explicitness that has been examined is variation in what might be called the completeness of arguments – that is, whether the advocate lays out explicitly the underlying bases of claims advanced by the message (provides explicit articulation of premises and conclusions, supporting information, and the like). For example, in research informed by Toulmin’s (1958) model of argument, Munch, Boller, and Swasy (1993) varied whether consumer advertisements explicitly stated the warrants for its arguments. O’Keefe’s (1998) meta-analytic review of 18 such studies reported a significant persuasive advantage (corresponding to a correlation of about .14) for messages with more complete supporting arguments. Thus more complete renditions of an advocate’s supporting arguments are likely to commonly engender greater persuasion.
In short, then, what relevant research evidence exists suggests that the normatively-desirable practice of clearly articulating one’s argumentative support – concretized here as specifically involving explicit identification of information sources and explicit statement of supporting arguments – will commonly make messages more persuasive. Thus with respect to this element of argumentative conduct, there appears to be no general conflict between normatively-sound practice and practical persuasive success.

2.3 Defense against counterarguments
A third expectation for normatively-sound argumentative practice is that arguers must be willing to defend their views against objections. The obligation to defend (rule 2 of van Eemeren et al., 1996, 283) contains the idea that an arguer must be willing to defend the advocated view against objections (attacks, counterarguments). That is, the normatively-responsible advocate, rather than ducking opposing arguments, confronts these head-on and attempts to defend against them, presumably by refuting them.
Quite a few experimental persuasion studies bear on the question of the relative persuasive effectiveness of ignoring as opposed to refuting opposing arguments. The relevant investigations are often labeled studies of “one-sided” messages (which ignore opposing arguments) versus “two-sided” messages (which discuss opposing arguments). But this contrast is insufficiently sharp for present purposes, because two-sided messages can vary in the way in which opposing arguments are discussed. Some instantiations of two-sided messages simply mention opposing considerations without specifically attacking them, but other versions of two-sided messages do attempt refutations of opposing arguments. The former sort of two-sided message (that is, nonrefutational two-sided messages) thus does not represent an attempt to defend the advocate’s standpoint; nonrefutational mention of opposing arguments discharges no argumentative burdens. The latter sort of two-sided message (refutational two-sided messages), on the other hand, does represent an effort at meeting the obligation to defend, and hence is of specific interest here.

O’Keefe (1999) reported a meta-analysis of 42 studies comparing the persuasive effectiveness of refutational two-sided messages and one-sided message. Refutational two-sided messages enjoyed a general persuasive advantage (corresponding to a correlation of .08) over their one-sided counterparts. That is to say, the normatively-desirable practice of defending against opposing arguments by refuting them – as opposed to simply ignoring such arguments – seems commonly to enhance persuasive effectiveness.
The effects of nonrefutational two-sided messages are also worth noticing in this context. Nonrefutational mention of opposing arguments, as mentioned above, does not represent an attempt at defending the advocate’s standpoint; indeed, if anything, it would seem to be an evasion of the responsibility to defend (though perhaps not so normatively dubious as ignoring opposing arguments altogether). Notably, nonrefutational two-sided messages are dependably less persuasive than their one-sided counterparts (O’Keefe, 1999; across 65 studies, the average effect corresponds to a correlation of -.05).
Thus when an advocate gives voice to opposing arguments without attempting to refute them – when the advocate as much as offers reasons to oppose the advocated view – then the advocate’s persuasive success naturally suffers. But when an advocate actively takes up the burden of refutation, persuasive success is likely to be enhanced. So here (again) there appears to be no conflict between normatively-desirable practice (defending against objections) and persuasive success.

2.4 Critical scrutiny of arguments
It is commonly taken to be normatively desirable that arguers carefully scrutinize arguments. This idea is more commonly implicit than explicit, but one recurring theme in argumentation studies concerns the value of close, careful attention to argumentative materials. Indeed, argumentation instruction often aims at enhancing argument-analysis skills (as distinct from argument-production skills) with the hope of encouraging closer (and more critical) scrutiny of arguments.
As it happens, there is some potentially illuminating persuasion research that bears on the question of the effects (on persuasive outcomes) of increasing message scrutiny. This research concerns the effects of variation in the amount of issue-relevant thinking in which message receivers engage (as indexed by, for instance, the number of issue-relevant thoughts that receivers list when asked to do so following exposure to a persuasive message). This issue-relevant thinking is commonly labeled “elaboration,” and one well-known model of persuasion processes – Petty and Cacioppo’s (1986) elaboration likelihood model (ELM) – treats elaboration variation as an important determinant of how persuasion operates. Of course, elaboration can take forms other than increased message scrutiny. For example, presented with a persuasive message, a receiver might be led to think about various arguments recalled from memory (as opposed to the arguments being presented in the message). But obviously one common realization of increased elaboration is increased message scrutiny (increased thinking about the message’s arguments).

So now consider the question of the effects (on persuasive outcomes) of increasing elaboration (and specifically increasing message scrutiny). One might plausibly entertain opposed hypotheses here. On the one hand, one might suppose that people can’t be persuaded unless they actually engage the message somehow – and hence one would expect that increasing elaboration could only enhance persuasion. On the other hand, one might suppose that increasing message scrutiny would naturally make receivers more critical of the message’s arguments – and hence one would expect that increasing elaboration could only diminish persuasion.
But the research evidence in hand suggests a much more complex picture, sufficiently complex that not all the details can be discussed here (for some recent discussions, see O’Keefe, 2002, 145-161; Petty & Wegener, 1998, 1999). However, there is one particular finding of special interest for the present enterprise, namely, the finding that increasing elaboration makes message receivers more sensitive to variations in the quality of the presented arguments.

The research evidence that bears on this conclusion consists of studies in which receivers are exposed to messages containing either high-quality arguments (good evidence, important consequences, sound reasoning, and the like) or low-quality arguments (weak evidence, trivial issues, poor reasoning, and so forth) under conditions in which the receivers’ degree of elaboration is likely to vary. A number of factors have been identified as influencing the degree of elaboration (including the personal relevance of the topic, personality dispositions, knowledge about the persuasive topic, and so forth), and such factors can be used to produce experimental variations in elaboration. So, for example, a large number of studies have varied the personal relevance of the topic as a means of influencing elaboration (because increased relevance produces increased elaboration).
Now as one might expect, higher-quality arguments are generally more persuasive than lower-quality arguments. But – and this is the result of interest here – the persuasive advantage of higher-quality argumentation is increased under conditions of higher elaboration (a result obtained in many studies; for a classic example, see Petty, Cacioppo, & Goldman, 1981). That is to say, the greater the scrutiny receivers give to messages, the more sensitive they are to variations in the argumentative quality of those messages. Of course, this is precisely the result one might hope for, in that it suggests that the normatively-desirable practice of attending closely to presented arguments has the effect of privileging (with respect to persuasive effects) more meritorious arguments (This treatment passes over some important complexities concerning the definition of argument quality in this research area. For discussion, see O’Keefe, 2002, 155-157; O’Keefe & Jackson, 1995).
But this does mean that there is potentially a conflict between normatively-desirable conduct and persuasive success, in the sense that a persuader will not necessarily want to enhance the degree of message scrutiny undertaken by receivers. Specifically, a persuader with poor-quality arguments will suffer (in terms of persuasive effects) as elaboration increases, and hence such a persuader would presumably be disinclined to do anything that might enhance critical scrutiny. Of course, on the other hand, persuaders with high-quality arguments will welcome such scrutiny. So enhancing message scrutiny is at least not necessarily inconsistent with persuasive success–and indeed under some circumstances enhanced message scrutiny will be likely to enhance persuasive effectiveness.

3. Conclusion
The claims offered here have to be seen as rather circumscribed. I am certainly not asserting that there are no persuasively-successful-but-ethically-dubious argumentative tactics. And I am not saying that normatively-good argumentative conduct is invariably rewarded with a corresponding persuasive payoff. But at least to some extent, it does seem as though some very general normative desiderata (with respect to argumentative conduct) are at a minimum not incompatible with practical persuasive success.
And perhaps it is worth noticing that the normative criteria explored here are rather fundamental elements of responsible argumentative practice – clearly articulating one’s claim, spelling out the support for that claim, meeting objections head-on, critically scrutinizing presented arguments. That these facets of normatively-desirable argumentative conduct are consistent with persuasive success suggests that – at least with respect to these very basic practices – persuaders do not face a choice between being normatively sound or practically persuasive.

Cathcart, R. S. (1955). An experimental study of the relative effectiveness of four methods of presenting evidence. Speech Monographs, 22, 227-233.
Cronin, M. W. (1972). An experimental study of the effects of authoritative testimony on small-group problem-solving discussions (Doctoral dissertation, Wayne State University, 1972). Dissertation Abstracts International, 33 (1973), 6485A. (UMI No. AAG-7312497)
Eemeren, F. H. van, & Grootendorst, R. (1984). Speech acts in argumentative discussions: A theoretical model for the analysis of discussions directed towards solving conflicts of opinion. Dordrecht/Cinnaminson: Foris Publications.
Eemeren, F. H. van, & Grootendorst, R. (1992). Argumentation, communication, and fallacies: A pragma-dialectical perspective. Hillsdale, NJ: Lawrence Erlbaum.
Eemeren, F. H. van, Grootendorst, R., Jackson, S., & Jacobs, S. (1993). Reconstructing argumentative discourse. Tuscaloosa, AL: University of Alabama Press.
Eemeren, F. H. van, Grootendorst, R., Snoeck Henkemans, F., Blair, J. A., Johnson, R. H., Krabbe, E. C. W., Plantin, C., Walton, D. N., Willard, C. A., Woods, J., & Zarefsky, D. (1996). Fundamentals of argumentation theory: A handbook of historical backgrounds and contemporary developments. Mahwah, NJ: Lawrence Erlbaum.
Evans, R. I., Rozelle, R. M., Lasater, T. M., Dembroski, T. M., & Allen, B. P. (1970). Fear arousal, persuasion, and actual versus implied behavioral change: new perspective utilizing a real-life dental hygiene program. Journal of Personality and Social Psychology, 16, 220‑227.
Jackson, S., & Jacobs, S. (1980). Structure of conversational argument: Pragmatic bases for the enthymeme. Quarterly Journal of Speech, 66, 251-265.
Luchok, J. A., & McCroskey, J. C. (1978). The effect of quality of evidence on attitude change and source credibility. Southern Speech Communication Journal, 43, 371-383.
Munch, J. M., Boller, G. W., & Swasy, J. L. (1993). The effects of argument structure and affective tagging on product attitude formation. Journal of Consumer Research, 20, 294-302.
O’Keefe, D. J. (1997). Standpoint explicitness and persuasive effect: A meta-analytic review of the effects of varying conclusion articulation in persuasive messages. Argumentation and Advocacy, 34, 1-12.
O’Keefe, D. J. (1998). Justification explicitness and persuasive effect: A meta-analytic review of the effects of varying support articulation in persuasive messages. Argumentation and Advocacy, 35, 61-75.
O’Keefe, D. J. (1999). How to handle opposing arguments in persuasive messages: A meta-analytic review of the effects of one-sided and two-sided messages. Communication Yearbook, 22, 209-249.
O’Keefe, D. J. (2002). Persuasion: Theory and research (2nd ed.). Thousand Oaks, CA: Sage.
O’Keefe, D. J. (in press). The persuasive effects of variation in standpoint articulation. In: F. H. van Eemeren (Ed.), Advances in pragma-dialectics. Amsterdam: Sic Sat.
O’Keefe, D. J., & Jackson, S. (1995). Argument quality and persuasive effects: A review of current approaches. In: S. Jackson (Ed.), Argumentation and values: Proceedings of the ninth Alta conference on argumentation (pp. 88-92). Annandale, VA: Speech Communication Association.
Petty, R. E., & Cacioppo, J. T. (1986). Communication and persuasion: Central and peripheral routes to attitude change. New York: Springer-Verlag.
Petty, R. E., Cacioppo, J. T., & Goldman, R. (1981). Personal involvement as a determinant of argument-based persuasion. Journal of Personality and Social Psychology, 41, 847-855.
Petty, R. E., & Wegener, D. T. (1998). Attitude change: Multiple roles for persuasion variables. In: D. T. Gilbert, S. T. Fiske, & G. Lindzey (Eds.), Handbook of social psychology (4th ed., Vol. 1, pp. 323-390). Boston: McGraw-Hill.
Petty, R. E., & Wegener, D. T. (1999). The elaboration likelihood model: Current status and controversies. In: S. Chaiken & Y. Trope (Eds.), Dual-process theories in social psychology (pp. 41-72). New York: Guilford.
Struckman-Johnson, D., & Struckman-Johnson, C. (1996). Can you say condom? It makes a difference in fear-arousing AIDS prevention public service announcements. Journal of Applied Social Psychology, 26, 1068-1083.
Toulmin, S. E. (1958). The uses of argument. Cambridge: Cambridge University Press.