Line Drawing

Alexander E. Hooke

Well, the line has to be drawn somewhere.

Overheard in moral conversations

Many logic or critical thinking textbooks treat the line-drawing fallacy as a footnote to or subcategory of another fallacy.

Depending on how one interprets a key premise or central term of the argument, detecting a line-drawing fallacy can take several forms. Consider a typical exercise in a textbook:

Officer: You are getting a ticket for driving at an unsafe speed.

Driver: Oh, then please tell me what is a safe speed? Is it 50 mph, 45 mph, or should I go so slow that I cause a traffic jam?

Clearly the irritated response imputes fallacious reasons to the officer’s actions, but it also commits a line-drawing fallacy by implicitly holding that

safe and unsafe are indistinguishable since there is no exact number on a car’s speedometer indicating an unsafe speed.

This line-drawing fallacy appears as a form of false dilemma since the driver distorts or limits the either/or options. It can also be a problem of vagueness as the key term “safe driving” is not clarified, to the chagrin of the driver. Line-drawing concerns also appear in slippery slope, hyperbole, and straw man fallacies. The driver, somewhat impudently and imprudently, challenges the officer with a critical thinking question that may thwart the possible compassion the officer has for an apologetic driver who might just receive a warning rather than a ticket.

In fact, the driver is implying a challenge to the officer that has perplexed philosophers for centuries.

To correct or to prevent such absurd conclusions, logicians try to identify and/or explain the nature of the line-drawing fallacy. Roy Sorensen, in discussing one of Zeno’s paradoxes, regards the line-drawing fallacy as a slippery slope. Once you disagree on the preciseness of point A or line B, then all points and lines are disputed. One way to avoid the paradox is to reassess the actual premises. Others view the line-drawing problem as an extension of the inability to agree on how to measure or evaluate the empirical aspects of an idea or concept. This either/or approach turns the line-drawing fallacy into a variation of the perfectionist or false dilemma fallacy. Those who emphasize vagueness contend that one or more of the central terms are imprecise and to prevent reaching an absurd conclusion, we need to assess or to agree on these terms.

Such cautions clearly can help the critical thinker to spot overt cases of sloppy thinking. When a petulant child whines about having to go to bed at 9 p.m., demands to know why 9:01 p.m. is any different, a line-drawing fal­lacy lurks on the horizon. Becoming a teenager, he or she will learn these arbitrary or imprecise distinctions when considering the proper age to drink or vote, the SAT score a college uses to accept or reject an applicant, when mom or dad are classified as senior citizens, or the official distinction between a freedom fighter and a terrorist. What makes this fallacy so impor­tant is that it intertwines with innumerable ordinary and controversial aspects of human life in which people are agreeing on or disputing where to draw the line.

To draw the line is a perennial source of cooperation and conflict. In sporting events, drawing lines demarcates what is in and out of play.

In international circles, drawing the line distinguishes respected borders and limits of military aggression. Among social contract theorists, drawing the line might determine where privacy ends and the public begins or when the personal domain becomes part of the communal.

This task is also evident in everyday concerns. Establishing the legal ages for voting or drinking, deciding when a stimulant becomes a drug, and distinguishing which student essay is a B+ rather than a B are just a sample of the many instances of when we draw a line, consciously or by habit. A recent animated film, Ted 2, drew rebuke for its humorous take on sickle cell disease. A president of a sickle cell organization called for movie makers and parents “to draw the line” on humor that disparages unfortunate victims of a debilitating disease.

Consider one ongoing and relatively recent controversy that illustrates the practical significance and philosophical difficulty in drawing the line. Visualize two photos, one of an anorexic teenage girl and the other an obese middle-aged tycoon. Asked to identify each one, no sensible person would fail. To explain the difference simply in terms of exact numbers, laymen as well as experts have trouble reaching a consensus. Such an inability to “draw the line” has animated social controversies about controlling diets and moral debates about proper eating, and has even been the unexpected cause of tragic accidents. For example, over the last two decades, several small planes have crashed due to excessive and unbalanced loads. The planes were originally built on the assumption that the average passenger weighed 160 pounds. Now, with so many overweight passengers or an imbalanced seating arrangement with too many obese people sitting on one side of the plane, several small planes have crashed at takeoff.

So the practical and philosophical underpinnings of line drawing show how the line-drawing fallacy can readily appear should arguments be devel­oped to support specific answers to some of the following questions. Should airlines begin charging fees based on passenger weight or assign obese peo­ple designated seats? Will this draw protests of bias or favoritism? Suppose fatness is not a medical term but a social construct, then isn’t this a moot issue? Can we sue the airlines for not safely determining in advance that passengers were gradually getting heavier?

In light of the above, a simple exercise:

Parent: Please stop eating all that junk food. It will make you fat.

Child: What’s wrong with a couple of chips and some ice cream? Do you want me to like those skinny models on TV?

Several line-drawing-related fallacies immediately arise, from false dilemma to straw man (distorting the parent’s point). Yet this exercise is too obvious to help a student discern the underlying difficulty in recognizing the line-drawing fallacy or avoiding the paradox it raises. As a potential critical thinker, the student or child might acknowledge his or her youthful moment of illogic, but then offer this more earnest rejoinder to the parent: “OK, but where do I draw the line? Exactly how do I decide when an occasional treat becomes too much snacking, or at which pound am I no longer normal but over­weight?” While we don’t expect youthful respondents to have Aristotle’s “means between the extremes” in the back of their minds, their questions seek some counsel about when or where to draw the line.

Margaret Cuonzo, in a lucid and scholarly discussion of paradoxes, devotes considerable attention to the sorites problem (the more formal category of line drawing) and possible solutions. One she proposes involves the notion of “folk concepts.” These refer to ordinary language terms that are not meant to be so precise and that undermine efforts to communicate or to deliberate ideas.

A shortcoming to the folk concepts approach is that folk concepts them­selves are hardly univocal in their meanings or standards. To assert that someone is skinny, normal, or fat is often based on tacit or subjective standards. They might rely on different criteria to make sensible judgments about beauty, health and longevity, functionality, liability for insurance companies, even the risk factor for flying in a small plane.

While the line-drawing fallacy can be subsumed under more standard fallacies, it warrants distinct attention insofar as it raises a perennial problem in everyday thinking and important disputes. Textbook exercises tend to present obvious cases of the fallacy. This has the inadvertent effect of students accepting the charge and moving on.

Instead, students and logic teachers might be encouraged to consider their own examples and experiences that reflect that drawing the line is one of the most enduring issues in critical thinking and philosophical reflection. Rather than offering the quick answer then checking the next exercise, we might first consider whether an apparent line-drawing fallacy can be resolved with a rational or successful decision about when or where the line should be drawn.

Reference

Moore, Brooke, and Richard Parker. 2007. Critical Thinking. Boston, MA: McGraw-Hill.