Sunday, September 14, 2008

.

Parallel lists

A kosher meatpacking plant in Iowa, the largest such plant in the country, has been in the news lately for non-kosher labor practices. In the latest round, they’re accused of violating child-labour laws. In the version of the report on National Public Radio’s news, the reporter said that their employment of under-age workers is “illegal because the children are exposed to dangerous chemicals, power machinery, and often work longer hours than permitted.”

Lists have to have parallel structure to make them easier to understand, but that’s a rule that’s violated more often than labour laws are. One can almost think of it mathematically: you ought to be able to “factor out” the common bits, or, alternatively, to factor them back in. Each item in the list should make sense if it’s attached to the “factored out” part by itself.

Let’s put NPR’s list in bullet form, to highlight the point:

It is illegal because the children are exposed to
  1. dangerous chemicals.
  2. power machinery.
  3. often work longer hours than permitted.
Item three is the odd one out: it doesn’t make sense when you stick it onto the introductory phrase.

So let’s back up:

It is illegal because
  1. the children are exposed to dangerous chemicals.
  2. the children are exposed to power machinery.
  3. the children often work longer hours than permitted.
There, that makes sense. We can still factor “the children” out, of course. And pulling it back to this point also shows us that “exposed to power machinery” is a somewhat awkward or unclear way to say it. Is it that they’re actually operating the power machinery? Or are they working in the area while someone else is operating it? The Times article tells us this:
The complaint charges that the plant employed workers under the legal age of 18, including seven who were under 16, from Sept. 9, 2007, to May 12. Some workers, including some younger than 16, worked on machinery prohibited for employees under 18, including “conveyor belts, meat grinders, circular saws, power washers and power shears,” said an affidavit filed with the complaint.

Then here’s another try:

It is illegal because the children
  1. are exposed to dangerous chemicals.
  2. operate power machinery.
  3. often work longer hours than permitted.
And putting it back into narrative form, their employment of under-age workers is “illegal because the children are exposed to dangerous chemicals, operate power machinery, and often work longer hours than permitted.”

We need to think about this when we’re writing presentations, where we often use bullet-lists and they’re often not written to be parallel. For example, this bullet list is from a recent presentation I attended:

Methodology:
  1. Identify business problems
  2. Discover and leverage existing activities
  3. Ongoing communication
  4. New technology evaluation
Please excuse “methodology” and “leverage”; I didn’t write the slide. The point is that the first two bullets are active — they have verbs and they tell us what the speaker is proposing to do — and the last two are passive — they don’t have verbs; they’re just noun phrases.

I’d rewrite the slide this way (leaving the business-speak alone, much as I’d like to change it):

Methodology:
  1. Identify business problems
  2. Discover and leverage existing activities
  3. Communicate regularly [with whom?]
  4. Evaluate new technology [for inclusion?]
That reads better, and it also points out that the last two bullets are missing something: without some specified target, they’re just empty phrases that mean nothing. Of course, that’s often why we write them the original way. “Ongoing communication” is clearly a good thing, and we want to avoid having to be too specific about it. But it makes for a weak presentation, and anyone who’s paying attention will see that.

It’s easy to say, when someone goes on about something like parallelism in lists, that it’s just unnecessary pickiness and “You understand what I’m saying.” But this parallelism thing isn’t just a random rule; thinking about this — and stuff like it — leads to clearer, more effective communication. Isn’t a better presentation worth it?

1 comment:

Dr. Momentum said...

I've never heard it put mathematically before. A sort of distributive property of lists. Nifty.