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4.2: Students Should Learn About the Logical Fallacies

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    Author: Daniel V. Bommarito, Bowling Green State University

    One measure of effective writing, when taught alongside argument and critical thinking, is the extent to which a writer identifies and roots out logical fallacies, both in others’ arguments and in one’s own. Variously defined as errors or flaws of reasoning, logical fallacies are generally thought to be violations in an argument that keep the truth of the matter, whatever it may be, somehow beyond the grasp of the writer and reader. In fact, such a view is so ingrained in our popular consciousness that it’s not uncommon for discussions of fallacies to slip into a hyperbolic, even religious tenor, as in the case of one highly trafficked blog on fallacies that commands across the top of its homepage, “Thou shalt not commit logical fallacies!” Such commandments rest on an assumption that by stamping out fallacies a writer’s ideas can stand firmly on the foundations of logic, thus free of obfuscation and open to unadulterated analysis. However, as with most rules associated with writing, the proscription of logical fallacies is more complicated than commonly thought.

    Logical fallacies earn the bad idea label because their application to writing and argument often serves as much to obstruct communication as not. I’ll admit this is an ironic claim, since fallacies are preserved in most writing guides because their identification and eradication are presumed to put arguments on firmer ground—but hear me out. Logical fallacies should be put out to pasture for three reasons: (1) defining logical fallacies is notoriously difficult and leads to selective attribution and enforcement; (2) identifying logical fallacies can actually work to shut down communication rather than energize it; and (3) attempting to adhere to proper logical form can stifle creativity and undermine one’s ability to wrestle

    with uncertainty. Taken individually, maybe none of these reasons would be enough to warrant casting fallacies aside altogether, but, taken together, they suggest a need to rethink how we define and use fallacies in the context of writing.

    An initial strike against logical fallacies is the lack of a clear definition or explanatory theory, despite having a rather long history. The notion of a logical fallacy can be traced back to Aristotle’s On Sophistical Refutations. There, Aristotle describes fallacies as “reasonings” that seem to be genuine “but are not so.” He illustrates with a few examples: Some people are beautiful, while others “seem to be so, by dint of embellishing themselves”; some people are physically fit, “while others merely seem to be so by blowing and rigging themselves out”; some inanimate objects really are gold, “while others are not and merely seem to be such to our sense.” You get the picture. Suffice it to say, on Aristotle’s account, fallacies are arguments that appear on the surface to be reasonable or logical but are not in reality.

    However, the philosopher Ralph H. Johnson believes that such a characterization doesn’t hold water because the recognition of a fallacy is entirely subjective. That is, what appears to be good reasoning to one person might very well be bad reasoning to another. Similarly, the philosopher Stephen Toulmin, whose work has been highly influential in the discipline of rhetoric and composition, puts an even finer point on it, saying that “we shall not be able to identify any intrinsically fallacious forms of arguing.” In other words, one person’s appeal to authority—to, say, the Bible for a historical account of the origin of life—might be perfectly reasonable to a person with the same set of values and expectations while that explanation would seem totally faulty to a person with different values and expectations. And no technical description of the reasoning itself, without reference to the particular circumstances in which the reasoning occurs, can explain why it may satisfy some and not others. For those committed to flagging fallacies and incriminating others for their misuse, these charges are at least a setback, if not a critical blow.

    But it gets worse. Even the ancients suspected that Aristotle’s notion of fallacies wasn’t all it was cracked up to be. For example, around the second century C.E., Sextus Empiricus—skeptical of logicians, philosophers, and just about anyone who claimed to have secure knowledge of any sort—found identifying fallacies to be misguided and ultimately useless. He held that fallacies could tell us nothing more about an argument than what we already knew. That is to say, an argument’s conclusion might be deemed false, not because of any technical knowledge of the way an argument unfolded, but because of the arguer’s prior knowledge of the issue under debate. As Sextus put it in an example, a person does not avoid a chasm at the end of the road because of his penetrating study of the road; rather, it is prior knowledge of a chasm at the road’s end that leads him to ignore the road altogether. In making such a claim, Sextus took dead aim at his contemporaries who believed they could diagnose arguments and explain why and how reasoning failed or succeeded as it moved from premises to conclusions. In effect, Sextus leaves us with a functional definition of fallacies that goes something like this: An argument is fallacious when it leads to conclusions that we already dislike or know to be problematic. Wholly unsatisfying, I should think, and contrary to what we tend to presume when it comes to studying the role of fallacies in arguments.

    Despite the problems identified by Sextus, Toulmin, and Hamblin, the tradition of fallacies has remained largely intact for over 2,000 years. Sure, theorists have rearranged the furniture a bit, as Hamblin tells us, but little if anything has been added or developed. Today, we continue to rely on the authority of tradition without paying much mind to that tradition’s shortcomings.

    A second strike against fallacies is that they can easily shut down debate rather than energize it. In fact, shutting down debate is precisely what Aristotle’s original discussion of fallacies was designed to do. The opening portion of On Sophistical Refutations indicates the type of argumentative dialogue Aristotle has in mind for the application of fallacies—namely, “contentious” dialogue. Contentious dialogue referred to the verbal sparring that took place in public contests between a protagonist and an antagonist, those who, in Aristotle’s words “argue as competitors and rivals to the death.” The aim of such competitions was the metaphorical death of an opponent, and there were five ways to bring about such a demise: (1) to win by refutation outright, (2) to show an opponent’s argument to be fallacious, (3) to lead the opponent into a paradox, (4) to force him into making a grammatical mistake, or (5) to reduce him to “babbling.” And of course, as Aristotle notes, it would also suffice “to give the appearance of each of these things without the reality.” The fallacies, then, were strategies taught to students so that they could learn to take down the opposition. Cast in this light, it’s not surprising that fallacy talk shows up frequently when someone wants to silence the opposition—literally to leave an opponent with nothing else to say, rather than engage in fruitful debate.

    A third strike, related to the second, is that too much concern for identifying and rooting out fallacies can inhibit creativity and keep people from wrestling with the uncertainties of daily life. The Italian professor of rhetoric, Giambattista Vico, made a similar claim as far back as the 18th century. Vico believed that his contemporaries’ preoccupation with formal logic was harmful to students because it dulled their natural creativity and, once they grew up, left them unpracticed in dealing with pressing social issues of the day, issues about which formal logic had little to offer. In place of teaching students to target and purge seemingly faulty reasoning, as was common in his day, Vico advocated teaching what rhetoricians call invention by way of the topics. Invention is the activity of drumming up arguments and is one of the key intellectual practices the discipline of rhetoric offers writers. The topics were helpful forms of reasoning that offered people strategies for producing arguments in a variety of contexts. Vico believed that this inventive process would capitalize on the natural creativity and imagination of young students and, most importantly, give them the tools needed to be well-rounded, prudent adults by the time they entered public life. For Vico, and indeed even for rhetoricians today, the narrow preoccupation with debunking flawed reasoning can stand in the way of such development.

    So what’s the take-away? Let me make three last points. First, writers benefit when they realize that fallacies exist in the eye of the beholder and that, by and large, people only search for fallacies when they already dislike something in an argument. Being on the lookout for fallacies will tell you more about the person doing the looking than it will about the argument itself.

    Second, writers benefit when they avoid seeing fallacies as endpoints or conclusions to arguments. Too often, fallacies conjure up combative exchanges that are focused more on winning than on moving toward some shared understanding. Rather than errors to identify and eradicate, fallacies can be indicators of something amiss that needs to be investigated further. At their best, fallacies can serve as starting points for fruitful dialogue, not endpoints.

    Third, writers benefit when they recognize that fallacies are a necessary part of the day-to-day, lived-in world, where incomplete knowledge and leaps of logic are a practical necessity. When writers approach communication as the messy business that it is, fallacies go from being violations of reasoning to the very reasons we continue conversing at all.

    By making this case against the traditional treatment of fallacies, I of course don’t mean to suggest that argument strategies cannot be deceptive or that reasoning cannot be abused. They can, and it often is. However, it is important to realize that the problem with fallacies (informal ones, at least) is not the thinking itself in any technical sense, but the spirit in which that thinking is undertaken and defended. Writers benefit when they understand and control fallacies, rather than see them as errors simply to be avoided.

    Further Reading

    Aristotle’s classic work discussing fallacies, On Sophistical Refutations, is accessible online through MIT’s The Internet Classics Archive, as is Aristotle’s Rhetoric, which can serve as useful complementary reading. For critiques of the tradition following Aristotle, see C. L. Hamblin’s Fallacies (Methuen Publishing) and Gerald J. Massey’s “The Fallacy Behind Fallacies” (Midwest Studies in Philosophy). Similar critiques of fallacies can be found in other volumes that also discuss practical reasoning more generally, including Stephen Toulmin’s The Uses of Argument (Cambridge University Press); Toulmin, Richard Rieke, and Allan Janik’s Introduction to Reasoning (Macmillan); and James Crosswhite’s The Rhetoric of Reason: Writing and the Attractions of Argument (University of Wisconsin Press).

    For examples of contemporary approaches to the teaching of fallacies, see Anne-Marie Womack’s article “From Logic to Rhetoric: A Contextualized Pedagogy for Fallacies” and Sharon Crowley and Michael Stancliff’s Critical Situations: A Rhetoric for Writing in Communities (Pearson). Womack’s approach moves fallacies to the center of class discussion and shows how fallacies can be used to conduct audience analysis. Crowley and Stancliff, while not discussing fallacies explicitly, emphasize rhetorical reasoning, which works to ground arguments, and the practice of argumentation itself, in particular historical contexts.

    Contemporary scholars of rhetoric have sought to develop alternatives to the agonistic view of argumentation that is so widely circulated. Wayne Booth’s The Rhetoric of Rhetoric: The Quest for Effective Communication (Blackwell) is a fine volume that offers an accessible discussion of the virtues and limitations of rhetoric and argumentation from a 21st-century perspective. Another fine work that considers alternatives to agonistic dialog is Krista Ratcliffe’s Rhetorical Listening: Identification, Gender, Whiteness (Southern Illinois University Press). Ratcliffe shows how understanding the logics underlying systems of thought can facilitate communication across cultural differences.


    argument, invention, logic, reasoning, rhetoric

    Author Bio

    Daniel V. Bommarito is an assistant professor at Bowling Green State University, where he teaches in the doctoral program in rhetoric and writing. His research explores composition theory and pedagogy, writing program administration, collaboration, doctoral education, and cross-cultural discourse.