Formal Logical Fallacies in Marketing: Introduction
This chapter introduces you to six formal logical fallacies in marketing compared to the 54 informal logical fallacies discussed in Chapter 5. Since most marketers’ arguments are inductive and not deductive in nature, one does not often come across formal logical fallacies in marketing. Nonetheless they do occur, and when they do, they can be subtle and lead to some disastrous outcomes if not checked.
Formal logical fallacies can be subtle for two reasons: First, they often sound valid. The statement, “Average sales for each of our sales reps increased six weeks after we initiated the new sales training program. That was a great sales training consultant we hired,” sounds valid, but isn’t, as you’ll read in the Affirming the Consequent vignette later in this chapter. Second, formal logical fallacies can be difficult to identify without examining the logical connections of the premises using pencil and paper, as we demonstrate in the upcoming Illicit Minor logical fallacy.
Recall that a formal logical fallacy is an argument form whose structure does not always guarantee that the argument’s conclusion is true. Another way of thinking about formal logical fallacies is that they are non sequiturs. Non sequitur means “does not follow.” So in a formal logical fallacy, the conclusion does not follow—it’s not guaranteed—from the argument’s premises.
The six formal logical fallacies that follow are culled from dozens that you can find on the Internet and they are the ones that we have most experienced in our marketing travels.
Location: Conference room at dry-cleaning franchise company.
Issue: The marketing team is debating why their franchisees’ sales have been declining over the past 18 months.
Karen (VP franchise relations): “We are, of course, worried about our franchisees’ sales because, if their sales go down, so do our profits.”
Jack (EVP marketing): “How do you explain this? It seems to me that either our franchisees’ customer service is declining or our franchisee marketing programs are not working.”
Karen: “I’ve reviewed the most recent marketing research studies, and they do show that customer satisfaction with our franchisees’ service has declined over the past 18 months.”
Jack: “That makes me feel a bit better, because I’d hate to think our marketing programs weren’t working.”
Jack is making a number of mistakes in his reasoning. Chief among them is that, when two reasons are offered to explain declining franchise sales, and if the evidence supports one of the reasons, then the other is false.
Definition: Affirming the Disjunct is a formal logical fallacy that takes the following structure:
1st Premise: If P or Q. |
Franchisees’ customer service is declining (P) or the company’s marketing programs are not working (Q). |
2nd Premise: P is true. |
Research supports that P is true. |
Therefore, Q is false. |
Therefore, the contention that our marketing programs are not working (Q) is false. |
In logic, a disjunction or “disjunct” is a compound sentence formed by combining two claims (i.e., statements) using the word “or.” In the previous argument, there is no logical reason why Q is false if P is true; thus, Jack’s statement is fallacious.
Discussion: The marketing world is often grey, not black and white, but people are often more comfortable with definitive answers.
In our example, there may be other reasons explaining why franchisees’ sales have been declining beyond simply poor customer service or a failed marketing program. For instance, a declining economy, more and better competitors, or changing traffic patterns and demographics in the stores’ trading areas, may explain declining sales. What’s more, the reasons may be difficult to express in an absolute form—the marketing program may not have failed per se, but it could be only 80 percent as effective as hoped.
Dealing with Affirming a Disjunct
Be on the lookout for arguments using the disjunct “or.” When you come across one, ask the following questions:
Are there just two or even one claim being considered to support a conclusion? In our example, Karen and Jack only identified poor customer service and a failed marketing program as potential causes of reduced store sales. Is the conclusion, if true, brought about by more factors?
Once you’ve identified the relevant factors supporting a conclusion, ask the following: Is it the case that a factor’s presence or nonpresence explains an outcome, or are there degrees to which a factor is present that best explains an outcome? In our case, it’s likely that the marketing program did not utterly fail—some parts of it probably worked and other parts either did not work well or indeed failed. Often, factors explaining a marketing outcome are not mutually exclusive.
Answers to the previous questions should help clear away muddled thinking that leads to Affirming a Disjunct. Whenever you encounter the word “or” in an argument, your fallacy detector should go off and lead you to examine all the alternatives more closely.
Location: Off-site meeting between Human Resources (HR) and the sales department.
Issue: HR and sales force management are reviewing the results of a sales training system the company has had in place for 18 months.
Tom (human resources VP): “My department has reviewed the sales force’s performance before and after we deployed the new training system. Sales are up and I, for one, would attribute that to the new training system. What do you think, Brian?”
Brian (sales VP): “Well, we spent a lot of time screening different training system companies, and it seems we selected the right one. I vote that we continue with the program.”
Tom: “I agree, Brian.”
Tom and Brian are assuming that the improved performance of the sales force can be attributed to the training program, and their inference seems reasonable. If the sales training program is effective, and all other factors are held constant, sales would increase. Sales increased; therefore, the sales training program has been effective. This conclusion may be correct, but the logic isn’t.
Definition: Affirming the Consequent is a type of argument that takes the following form:
Premise: If A is true, then B is true.
Premise: B is true.
Conclusion: Therefore, A is true.
In the previous vignette, Tom’s argument takes this form:
Premise: (A) If the sales training system is effective, then (B) sales will increase.
Premise: Sales increased.
Conclusion: Therefore, the training system is effective.
However, Tom’s argument is not valid. Validity in this context means that, if his argument’s premises are true, his conclusion is guaranteed to be true. The classic example of this kind of validity, which you probably first came across in college, is demonstrated in the following argument:
Premise: All men are mortal.
Premise: Socrates is a man.
Conclusion: Therefore, Socrates is mortal.
In this example, the premises are true and, as such, they logically guarantee the conclusion to be true—if Socrates is a man and all men are mortal, by definition, Socrates is mortal. In contrast, the logical structure of Tom’s argument simply does not guarantee his conclusion to be true because other factors may have caused the sales increase. “If the sales training system is effective, then sales will increase” is Tom’s premise but it is not a truism like “All men are mortal.” Tom set it out as a true premise but that does not mean it is true. Training is not guaranteed to achieve the results; it might, it should, but it is not a certainty. Sales and training have a more complex relationship than death and taxes.
Discussion
Sales might have increased, for instance, because of an improving economy, mistakes made by competitors, changing consumer tastes, or the simple fact that the sales force is 18 months older and more experienced. Of course, you might find this to be a trivial logical fallacy or one that is self-evident. After all, we all know that “correlation is not causation.” Nevertheless, training programs are expensive and management should require better justification to approve such expenditures.
Tom should be looking for multiple, empirically based indicators that support the belief that the sales training program is working. He should not just focus on the single metric of sales volume if he wants to make a strong argument supporting his conclusion.
Think of it this way: If the sales training system is working, what else should be true? Example empirical indicators that could corroborate Tom’s claim might be the following: After the sales training program, 1) the percentage of initial prospecting calls that result in a sale increase; (2) reps follow up customers’ inquiries quicker; (3) there are fewer customer complaints; and, (4) customers express a higher level of satisfaction with the sales force’s performance. The more relevant evidence Tom can produce to support his claim, the stronger his argument will be that the training program actually affected sales positively.
Dealing with Affirming the Consequent
When a colleague confronts you with an argument that affirms the consequent, employ the following two strategies. First, simply point out that there are potentially multiple causes of “B”–the consequent of whatever “A” is. Second, help your logically challenged friend think through the following question: If A is true, what else should be true in addition to B? If you can’t think of anything, then maybe A is false.
Remember, antecedents don’t necessarily guarantee consequents. Correlation is not causation.
Location: McDonald’s headquarters.
Issue: How should the corporation reinvigorate coffee sales in Australia? (Note to any McDonald’s employees: this is an apocryphal interpretation of a case study found in Byron Sharp’s textbook, Marketing: Theory, Evidence, Practice.)1
Ethan (vice president, marketing for McDonald’s Australia): “So, Emma, your team was charged with coming up with a strategy to revive our coffee sales. What is your team’s recommendation?”
Emma (product marketing manager): “We concept tested a new idea, Ethan, based on an image study we did on our brand last year. Our team does not feel that we can ever be a serious competitor to Starbuck’s if we try to continue to sell premium and sophisticated coffees in our current channel of McDonald’s restaurants. Our restaurants just don’t have a premium or sophisticated image—face it, we’re a fast-food restaurant. Consumers just don’t link premium coffees with our restaurant brand. We believe that we need to break out with a totally new channel—a new retail outlet, with a new name, and image.”
Ethan: “No way that’s going to work, Emma. Other retailers have sold premium brands without creating a new channel and store brand—heck, you can buy a high end model of a Maytag washer and dryer at Sears; and even Kohl’s department store sells the Ralph Lauren brand. No way. We just have to figure out how to sell a premium coffee in our existing restaurants.”
Emma: “I see your point.”
Clearly, Emma did not make the best argument for her recommendation. For example, she might have conducted a research study on the proposed McCafé concept—and had it received a positive reaction from target consumers, she could have used those results to support her team’s recommendation. Ethan is using her poor argument to conclude that Emma’s team’s recommendation is no good.
Definition: Bad Reasons is a formal logical fallacy in which “a conclusion is false because an argument given for it is bad.”2 Its logical form is as follows:
Premise: Argument P for conclusion Q is bad.
Conclusion: Therefore, Q is false.
Discussion
This fallacy most likely manifests itself in a group setting when several people are debating the goodness of one or more arguments. The motivation behind using the Bad Reasons fallacy is simply this: If a person can show that another’s argument is poor or weak, that fact can be used to bolster one’s own argument. As Gary Curtis says on his website, Logical Fallacies:3
It is always tempting, in the heat of debate, to think that one has established one’s own case when all that one has succeeded in doing is undermining the opposition’s case. To commit the Bad Reasons Fallacy is to act as though argumentation is a zero-sum game in which, if the other side loses, then you win.
Dealing with Bad Reasons
Don’t put yourself, or your team, in a position in where a colleague can leverage your poor argument to his or her advantage. One way to accomplish this is not to present your recommendation as an argument—that is, as a well-thought-out set of statements comprised of premises and a conclusion designed to persuade others to accept it. Rather, offer your idea as a suggestion that will take some time and research to investigate. Only when you are ready to defend your argument should you present it to others for critique.
If you read Sharp’s case study, you’ll discover that “Emma’s recommendation” turned out to be a grand success. Now, take a break from reading our book and go to your local McCafé and have a good cup of coffee.
Location: Office of the VP of HR in a large vehicle parts manufacturer.
Issue: The VPs of HR and sales are discussing the criteria for hiring new salespeople.
Jacqueline (VP HR): “I understand that you’ve been doing some research on your sales force and you’d like the HR department to screen applicants differently than we have in the past. What’s your recommendation?”
John (VP sales): “This is what we discovered. Nearly all MBAs with bachelor’s degrees in business have performed well as sales people. Also, in reviewing past applications, few undergraduate humanities majors have MBAs. So in the future don’t pass on to us any humanities majors. They likely will not make good salespeople, and interviewing them is mostly a waste of our time.”
Jacqueline: “That makes sense to me. Plus, it saves both your department and mine valuable time we can invest elsewhere.”
On the surface, John’s argument seems to make sense, but it is not deductively valid. The truth of his premises—(1) that nearly all MBA’s with bachelor’s degrees in business are good salespeople and (2) that few undergraduate humanities majors have MBAs—do not guarantee his conclusion—that humanities majors lacking an MBA are not good sales-people—is true. This is an example of a fallacy known as “Illicit Major.”
Definition: Illicit Major takes the following form:
All A’s are B’s.
No C’s are A’s.
Therefore, no C’s are B’s.
You can see that the truth of the premises does not guarantee the truth of the conclusion in the following popular example of this fallacy:
All cats (A) are mammals (B).
No dogs (C) are cats (A).
Therefore, no dogs (C) are mammals (B).
Discussion
Attributed to Aristotle, deductive arguments containing two premises and a conclusion are called categorical syllogisms. The two premises are composed of a general statement (called the major premise) and a specific statement (called the minor premise), such that the truth of these premises guarantees the argument’s conclusion. The most famous of these is: All men are mortal (the general statement); Socrates is a man (the specific statement); therefore, Socrates is mortal (the deduced conclusion).
In Illicit Major, no statement is made that relates B to C or to not-C. Consequently, some not-C’s could be B’s. In our example, some undergraduate humanities majors without MBAs might just be good salespeople!
In reality, John may realize this, but he simply wants to “play the probabilities”—undergraduate humanities majors without MBAs just don’t seem the type to be good salespeople. But accepting conventional wisdom disguised in an Illicit Major may blind you to valuable opportunities. Consider:
All tech company employees (A) are tech-savvy (B).
No high school-only graduates (C) are tech company employees.
Therefore, no high school-only graduates are tech-savvy.
Dealing with Illicit Major
Google wants to hire tech-savvy employees; however, after extensive data analysis, Google’s senior vice president for People Operations, Laszlo Bock, says that relying on college transcripts and standardized testing is not predictive of Google employee success. He says:
One of the things we’ve seen from all our data crunching is that G.P.A.’s are worthless as a criteria for hiring, and test scores are worthless—no correlation at all except for brand-new college grads, where there’s a slight correlation. Google famously used to ask everyone for a transcript and G.P.A.’s and test scores, but we don’t anymore, unless you’re just a few years out of school. We found that they don’t predict anything.
What’s interesting is the proportion of people without any college education at Google has increased over time as well. So we have teams where you have 14 percent of the team made up of people who’ve never gone to college.4
Google understood the error of the Illicit Major, and it has changed the way it hires employees as a result. So, in dealing with this fallacy, remember Google!
Location: Conference room at Advanced Technologies’ advertising agency.
Issue: How to best target web advertisements for the company’s products.
George (Advanced Technologies’ advertising department director): “Jill, your agency has been tasked to research the best ways to target prospects with web ads for the new product. What have you come up with?”
Jill (the agency’s research director): “We discovered several factors that may play a role in targeting the best prospects. As you’d expect, all consumers in the Progressive Segment are prospects for the new product.
George: “That’s what we were hoping for. With our web analytics tools, we can identify the people who visit certain web sites and whether they fit our Progressive Segment profile or not. What else did you learn?”
Kelly (the agency’s research manager): “We discovered that all prospects are families with at least two children in the household. So, based on what Jill said, we can safely assume that all two-plus kid households are in the Progressive Segment, and our web analytics can easily ID these particular households as well.
Kelly may be correct, but her conclusion that all prospects are families with at least two children in the household is not a deductively valid statement. Let’s explore why.
Definition: Illicit Minor is a formal logical fallacy that takes the following form:
All A’s are B’s.
All B’s are C’s.
Therefore, all C’s are A’s.
However, some C’s may not be A’s.
Discussion
Let’s examine Jill and Kelly’s argument more formally:
All consumers in the Progressive Segment (A) are prospects (B).
All prospects (B) are households with at least two kids (C).
Therefore, all households with at least two kids (C) are in the Progressive Segment (A).
Figure 4.1 Two situations that are consistent with Jill’s argument
What Kelly said certainly seems reasonable, but Jill’s statement that “All consumers in the Progressive Segment (A) are prospects,” does not mean that all prospects are exclusively in the Progressive Segment, which, if they were, would make Kelly’s statement correct.
At least two vastly different situations are consistent with Jill’s argument, as shown in Figure 4.1. In both Situation A and B, all Progressive Segment members are two-plus kid households; however, in Situation B, most two-plus kid households are not prospects!
Dealing with Illicit Minor
We believe that the best way to deal with this fallacy is simply to restate the chain of logic back to the person who made the argument. Another useful tool can be to draw a Venn diagram giving a counter example to the argument, and asking (using our previous example): “What evidence do we have that supports Situation A versus Situation B? Which is more plausible? Is there another interpretation to the relationships among the Progressive Segment, prospects, and households with two-plus kids that is a more accurate description of this market?”
Sometimes the best way to understand a logic problem is to draw a picture of it.
Negating Antecedent and Consequent
Location: In the kitchenette next to the coffee machine. You know, the one near the large conference room on the third floor.
Issue: How should we be looking to execute a new e-commerce channel partnership with our dealers?
Don (sales leader): “Most of our competitors let their dealers maintain a web site where they can conduct both product and service transactions with their customer base. Clearly it has proven to be a good way to compete since it has become such a standard practice in our industry.”
Julio (marketing leader): “I want to propose we put in place some different mechanisms to control this channel. I think we should front-end the transaction with our own site and then either pass the sale on to the dealer if they have stock or drop ship it and give the dealer a commission on the sale.”
Don: “Our competition is not doing it that way, so I have to assume it is not a good way for us to compete.”
Julio: “Wait, I think you have your logic mixed up.”
Julio is pointing out a logical fallacy known as “negating antecedent and consequent.”
Definition: In Negating Antecedent and Consequent, say that someone proposes: “If X is true, then Y is true.” If this is, indeed, a valid statement, then the following proposition is false: “If X is not true, then Y is not true.” Y may be true for other reasons, even if X is not true.
For example, assume the following statement is valid: “If it rains (X), then the sidewalk is wet (Y).” Then the next statement is not valid: “If it does not rain (not-X), then the sidewalk is not wet (not-Y).” It may not be raining, but I could be watering my lawn, which makes the sidewalk wet.
Assume that If X, then Y, is a valid statement. |
|
Then, this transpositional form (a) is also valid: (a) If not-Y, then not-X. |
But, this transpositional form (b) is not valid: (b) If not-X, then not-Y. |
Let’s see how this logical fallacy tripped up Don.
Discussion
Don’s underlying logic is as follows: “If X (competitors are doing what he describes above), then Y (it’s a good way to compete).” Julio offers an alternative strategy—“not-X”—and states that it, too, is a good way to compete.
However, Don then makes the illogical leap in critiquing Julio: “If Julio’s strategy is not-X” [that is, it is not the same as mine], then it is not a good way to compete.” Don unconsciously used the transpositional form (b), which is not valid. Again, it is not valid because there may be other “good ways to compete” that differ from Don’s “X.”
Dealing with Negating Antecedent and Consequent
Julio has started off right by saying, “Wait, I think you have your logic mixed up.”
However, Julio needs to further explain that, while Don’s statement may be correct—and Julio does not dispute Don’s statement—what it does not do is prove that something untried (e.g., Julio’s idea) is not a good way to compete as well.
In short, “If X, then Y” is true, does not mean that “If not-X, then not-Y” is true as well. If the dog had not stopped to sniff the tree, he would have caught the rabbit, does not mean that if he had ignored the tree, he would have caught the rabbit.