The Fallacy of the False Cause
by Rick Brenner
Although we sometimes make decisions with incomplete information, we do the best we can, given what we know. Sometimes, we make wrong decisions not because we have incomplete information, but because we make mistakes in how we reason about the information we do have.
Ginny was getting pretty steamed. "We tried code inspections back in Release 5, and you know what happened then. Everything slowed down, we got nothing done, everyone got into fights, and Morgan left the group. If we have to do inspections, you can count me out." Ginny's argument, in essence, was that since some unpleasant events happened shortly after inspections began, the code inspections caused them.
Arguments based on the
Fallacy of the False Cause
to make costly errorsAlthough her argument is convincing to many, it doesn't prove her case. It's an example of a rhetorical fallacy called post hoc ergo propter hoc — Latin for after this, therefore because of this. Ginny argues that since the unpleasant events followed the adoption of code inspections, the code inspections caused the problems, and therefore all code inspections, of any kind whatever, are bad.
A more convincing argument would exclude other possible causes. For example, were the inspections run badly? Were people inadequately trained? Were inspections introduced when people were too busy to learn how to do inspections?
The Post Hoc fallacy is a special case of a more general type of fallacy — the fallacy of the false cause. In Post Hoc, the apparent causal connection relates to the timing of the two events. But connections can also be unrelated to timing:
All of the projects Gerhard has managed in the past few years have been late and over budget. Since people now believe that Gerhard was the cause of the overruns, he can no longer get assignments as a project lead. Nobody seems to remember that each of Gerhard's project sponsors had either reduced his budget or expanded requirements so many times that no project manager would have had much of a chance to perform well.
Gerhard's management skill was the most obvious factor common to the failed projects, but it wasn't the cause. In this case, faulty reasoning damages a career and deprives the company of a skilled manager.
How can you spot this kind of error in the heat of debate? The fallacy of the false cause might be lurking if the argument states that:
Since A was present when B occurred, then A was the cause. Or Since A preceded B, A caused B.
To respond to arguments that use this fallacy, use examples in which A was present, but B wasn't. Your debate partner might not be convinced, but it's your best shot.
Educate your colleagues about the Fallacy of the False Cause. When we understand how much it can cost, and when we understand how to avoid it, we can save much pain and frustration. Perhaps Will Rogers said it best:
It's not what we don't know that hurts; it's what we know that ain't so.
Top Next Issue
The article you've been reading is an archived issue of Point Lookout, my weekly newsletter. I've been publishing it since January, 2001, free to all subscribers, over the Web, and via RSS. You can help keep it free by donating either as or as . You'll receive in return my sincere thanks — and the comfort of knowing that you've helped to propagate insights and perspectives that can help make our workplaces a little more human-friendly. More
Your comments are welcome
Would you like to see your comments posted here? Send me your comments by email
, or by Web form
About Point Lookout
Thank you for reading this article. I hope you enjoyed it and found it useful,
and that you'll consider recommending it to a friend
Point Lookout is a free weekly email newsletter. Browse the archive
of past issues. Subscribe for free.
Support Point Lookout by joining the Friends of Point Lookout,
as an individual or as an organization.
Do you face a complex interpersonal situation? Send it in,
anonymously if you like, and I'll give you my two cents.
More articles on Emotions at Work
- What's So Good About Being Laid Off?
- Layoffs during the holiday period of November 15 through January 15 are far more common than you might think. Losing your job, or fearing that you might, is always difficult, but at this time of year it's especially helpful to keep in mind that the experience does have a bright side.
- Irrational Self-Interest
- When we try to influence others, especially large groups or entire companies, we sometimes create packages of incentives and disincentives that are intended to affect behavior. These strategies usually assume that people make choices on rational grounds. Is this assumption valid?
- Hurtful Clichés: Part I
- Much of our day-to-day conversation consists of harmless clichés: "How goes it?" or "Nice to meet you." Some other clichés aren't harmless, but they're so common that we use them without thinking. Maybe it's time for some thought.
- The Injured Teammate: Part I
- You're a team lead, and one of the team members is very ill or has been severely injured. How do you handle it? How do you break the news? What does the team need? What do you need?
- When Change Is Hard: Part I
- Sometimes changing organizations goes smoothly. More often, it doesn't. Whatever methodology we use — and there are many methodologies available — difficulties can arise. When change is hard, what's happening? What makes change hard?
See also Emotions at Work, Critical Thinking at Work and Rhetorical Fallacies for more related articles.
I offer email and telephone coaching at both corporate and individual rates.
Contact Rick for details at rbrenner@ChacoCanyon.com
or (617) 491-6289, or toll-free in the continental US at (866) 378-5470.
Get the ebook!
Past issues of Point Lookout
are available in six ebooks:
Reprinting this article
Are you a writer, editor or publisher on deadline?
Are you looking for an article that will get people talking and get compliments flying your way? You can have 500 words in your inbox in one hour. License any article from this Web site. More info
- Cognitive Biases and Workplace Decision-Making
- For most of us, making decisions is a large part of what we do at work. And we tend to believe that we make our decisions rationally, except possibly when stressed or hurried. That is a mistaken belief — very few of our decisions are purely rational. In this eye-opening yet entertaining program, Rick Brenner guides you through the fascinating world of cognitive biases, and he'll give concrete tips to help you control the influence of cognitive biases. Read more about this program. Here's an upcoming date for this program:
- MITRE, in Bedford, MA: October 21, Monthly Meeting, Boston SPIN.
- The Politics of Meetings for People Who Hate Politics
- There's a lot more to running an effective meeting than having the right room, the right equipment, and the right people. With meetings, the whole really is more than the sum of its parts. How the parts interact with each other and with external elements is as important as the parts themselves. And those interactions are the essence of politics for meetings. This program explores techniques for leading meetings that are based on understanding political interactions, and using that knowledge effectively to meet organizational goals. Read more about this program. Here are some upcoming dates for this program:
- Managing Virtual Meetings for Real Results
- Leading or participating in virtual meetings — teleconferences, Web conferences, video conferences, and more — is challenging. Miscommunications, misunderstandings, distractions, politics, and interpersonal conflict all thrive in the typical environment of the virtual team. We'll inventory the challenges virtual meeting leaders and participants face, and provide tools for anticipating and addressing them. The focus of this program is practical — attendees will learn concrete techniques for preventing and dealing with the problems that arise in virtual meetings. Read more about this program. Here's an upcoming date for this program:
- The Race to the South Pole: Ten Lessons for Project Managers
- On 14 December 1911, four men led by Roald Amundsen reached the South Pole. Thirty-five days later, Robert F. Scott and four others followed. Amundsen had won the race to the pole. Amundsen's party returned to base on 26 January 1912. Scott's party perished. As historical drama, why this happened is interesting enough, but to project managers, the story is fascinating. Lessons abound. Read more about this program. Here's an upcoming date for this program: