The Fallacy of Composition

In group discussions, debates about issues are informal and sometimes fast-moving. They can move so quickly that the group's members don't realize that they have reached incorrect conclusions. When this happens, one or more rhetorical fallacies probably played a role — accidentally or intentionally inserted by one of the group's members.

Because of its subtlety, the Fallacy of Composition is a favorite of those who intentionally use rhetorical fallacies. When people use the Fallacy of Composition, they make statements about some parts of a whole (or even every part of a whole), and then conclude something about the whole. To illustrate the use of the fallacy, here's a particularly transparent form, just to give you the idea of how it works:

Since the global economy is in recession, and our jobs are less secure than they once were, everyone should pay off their debts and increase the fraction of their income that they save.

If we were to follow this advice, the recession would quickly become a depression, because economic activity would contract severely. Although the statement is probably true for individuals, the conclusion about the entirety of all individuals is false.

The Fallacy of Composition also occurs in group discussions about managing projects:

We can make up some time and get closer to the original schedule if Tim and Ellen work through the weekend. So it's probably best if everyone works every weekend for the rest of the project.

If we take this approach, people will become fatigued, their work quality will degrade, some will seek reassignment, and the project might never complete.

Here's an example in which an approval board finds two issues in a proposal, and then rejects the entirety on that basis:

We've found serious problems in the proposal. The Localization budget is too low, and the schedule for customer extensions is too aggressive. You need to rethink the whole thing.

The above Because of its subtlety,
the Fallacy of Composition
is a favorite of those
who intentionally use
rhetorical fallaciescomment omits any proof that the two flaws cited are justification for the final recommendation.

And from Glen's performance review:

I'm sorry I couldn't recommend you for a promotion this year. You had some trouble working with Fran, and there were also problems with Leo. You need to learn how to work better with people.

Perhaps the conclusion above is correct, but two difficult relationships are probably not adequate proof. For instance, if both Fran and Leo have problems with everyone, perhaps the problem isn't Glen's. This application of the Fallacy of Composition offers a convenient alternative to justifying decisions made for other reasons.

One important distinction between a Fallacy of Composition and valid inductive reasoning is the nature of the generalization. An inductive argument contains a proof of its generalization; a fallacy of composition merely suggests its generalization. It is the subtlety of this distinction that makes the Fallacy of Composition so difficult to identify in the moment.  Top    Next Issue

Do you spend your days scurrying from meeting to meeting? Do you ever wonder if all these meetings are really necessary? (They aren't) Or whether there isn't some better way to get this work done? (There is) Read 101 Tips for Effective Meetings to learn how to make meetings much more productive and less stressful — and a lot more rare. Order Now!

Your comments are welcome

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.

This article in its entirety was written by a human being. No machine intelligence was involved in any way.

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.

Related articles

More articles on Effective Meetings:

Overtalking: II

Overtalking is a tactic for dominating a conversation by talking to stop others from talking. When it happens, what can we do about it?

Meta-Debate at Work

Workplace discussions sometimes take the form of informal debate, in which parties who initially have different perspectives try to arrive at a shared perspective. Meta-debate is one way things can go wrong.

Preventing Sidebars

Sidebar conversations between meeting participants waste time and reduce meeting effectiveness. How can we prevent them?

How to Waste Time in Virtual Meetings

Nearly everyone hates meetings, and virtual meetings are at the top of most people's lists. Here's a catalog of some of the worst practices.

Workplace Politics and Social Exclusion: I

In the workplace, social exclusion is the practice of systematically excluding someone from activities in which they would otherwise be invited to participate. When used in workplace politics, it's ruinous for the person excluded, and expensive to the organization.

See also Effective Meetings for more related articles.

Forthcoming issues of Point Lookout

Coming July 2: The True Costs of Contractors

Among the more commonly cited reasons for hiring contractors instead of direct employees is cost savings. But are these savings real? Direct compensation, including perks and benefits, might favor the contractor arrangement, but indirect costs tell another story. Available here and by RSS on July 2.

And on July 9: On Being Seriously Funny at Work

Humor is such a valuable tool at work that it ought to be recognized as an official contribution by team members who provide the laughs that keep some teams from auto-destructing. Even if you're not known for bringing the funny, there are a few simple techniques that can change your image. Available here and by RSS on July 9.

Coaching services

I offer email and telephone coaching at both corporate and individual rates. Contact Rick for details at rbrenaXXxGCwVgbgLZDuRner@ChacDjdMAATPdDNJnrSwoCanyon.com or (650) 787-6475, or toll-free in the continental US at (866) 378-5470.

Get the ebook!

Past issues of Point Lookout are available in six ebooks:

• Get 2001-2 in Geese Don't Land on Twigs (PDF, )
• Get 2003-4 in Why Dogs Wag (PDF, )
• Get 2005-6 in Loopy Things We Do (PDF, )
• Get 2007-8 in Things We Believe That Maybe Aren't So True (PDF, )
• Get 2009-10 in The Questions Not Asked (PDF, )
• Get all of the first twelve years (2001-2012) in The Collected Issues of Point Lookout (PDF, )

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 500-1000 words in your inbox in one hour. License any article from this Web site. More info