Chaim Perelman

Chapter 4: Arguing Quasi-Logically

CHAPTER 4 Arguing Quasi-Logically N ow that we have scrutinized the philosophical underpinnings of Perelman’s rhetorical thought and have analyzed the concept of rhetorical audience lying at its core, we are ready to examine the typology of argumentation set forth in The New Rhetoric. After discussing facts, truths, presumptions, and other “starting points” upon which arguments can be constructed, Perelman and Olbrechts-Tyteca proceed to explain the discursive techniques used by arguers to elicit agreements or “adherences ” from their audiences. Arguments are sometimes structured in the form of an association, or liaison, in which the adherence accorded the premise is transferred to the conclusion; at other times, arguments are presented in the form of a dissociation, which seeks to persuade or convince an audience by separating elements of thought that were previously tied together, either by language or by a recognized tradition. As we saw in Chapter 2, Perelman’s early investigations in the 1930s, when he was still “imbued with positivism,” revealed that beneath all knowledge claims lie axioms that cannot be postulated as self-evident, and whose selection cannot entirely escape the charge of arbitrariness. Furthermore , his analyses of logical fallacies, conducted from the same rationalistic paradigm, led him to conclude that formal logic—the only logic practiced by contemporary logicians—had become largely irrelevant to all practical reasoning about human affairs. Even as he came to this conclusion, Perelman recognized that the notion of logic continues to exert a powerful sway over the modern mind. To charge one’s opponent with being “illogical” is to hurl a stinging rebuke, one that invites an immediate denial or rebuttal. This occurs in philosophical circles, courtroom settings, or even in conversations around the family dinner table. Presenting one’s own arguments as 44 chaim perelman “logical,” on the other hand, goes a long way toward assuring them a favorable hearing. If logic is indeed irrelevant to practical decision-making, how is it that its attraction remains so psychologically compelling? Perelman and OlbrechtsTyteca scoured the logic books in vain, looking for a resolution to this dilemma . Finally, their extensive field investigations of argumentative practices yielded the solution, which appeared in the form of a species of arguments exhibiting a peculiar rhetorical property: these arguments owe their potency to their similarity to well-established formal structures. “Quasilogical arguments,” as the Belgian researchers dubbed them, “lay claim to a certain power of conviction in the degree that they claim to be similar to the formal reasoning of logic or mathematics” (The New Rhetoric 193). Any similarity between these arguments and formal reasoning, however, turns out to be purely illusory, as any careful analysis will reveal. As a case in point, take the following argument, which resembles a logically valid syllogism: Conservatives support the preservation of the status quo. Jones is a conservative. Hence, Jones supports the existing policies of the present administration. Unlike a chain of formal reasoning, this argument contains terms that are not univocal. The term status quo in the major premise cannot be equated with the “policies of the present administration” in the conclusion, nor is the term “conservative” defined precisely enough to carry the same denotation in both premises. (In logic, this is known as the fallacy of the “undistributed middle.”) Without putting too fine a point on the matter, we can say that this argument has a superficial plausibility, owing in part to its resemblance to the familiar logical pattern of deduction. But even a cursory examination shows it cannot meet the tests of formal validity. Because an arguer seeks the adherence of an audience, not formal validity, however, his or her goal is not to establish a chain of reasoning in which some ideas are derived from others according to accepted rules of inference. “The quasi-logical argument’s lack of rigor and preciseness may seem to be a logical flaw,” writes Perelman, “but to charge a person with using a logically flawed argument would make sense only if that person claimed to advance a logical demonstration” (Realm of Rhetoric 53). Quasi-logical arguments are not simply deceptive or imprecise versions of the real thing; they are neither correct nor incorrect, but are weaker or stronger, depending upon how well they are reinforced by other kinds of arguments. Instead of relying on a chain of reasoning, argumentation consists of “a web formed from all the arguments Arguing Quasi-Logically 45 and all the reasons that combine to achieve the desired result” (The New Rhetoric and...