The Science of Simple Writing

Using Flesch–Kinkaid to punch up your prose and be a better writer

Steve Chatterton
Dec 6, 2017 · 5 min read

Abstract: The whole point of writing is to spread ideas. To make ourselves better understood. To that end, we should do all we can do to write simply. To make our writing plain and easy to understand. This article looks at the work of Flesch and Kincaid and the science behind simple writing. It also suggests how you can put their work to use in your writing for greater impact.

Photo Credit: trustypics

Short words good. Short sentences? Better!

I used to love big words. The bigger the better, really. I took great pride in my big brain and wanted the whole world to know how clever I was.

It wasn’t until much later that I realized I was an idiot. No one cares about my vocabulary. My eloquence is irrelevant. If people have to work so hard to follow my train of thought, where is their motivation to try?

Good writing is about sharing interesting ideas, and the best way to do that is to write plainly.

Write better, with science!

Dr. Rudolph Flesch fled Austria to escape the Nazis. He settled in America and went to Columbia where he earned a Ph. D in Library Science.

Flesch obsessed over clear writing and wrote several books on the topic. He took issue with the teaching methods of the day which pushed for rote memorization. His best-known book, Why Johnny Can’t Read, called for a return to good old-fashioned phonics. And his ideas caught on, too. You may not know his work, but you likely know the most-famous book inspired by it; The Cat in the Hat by Dr. Suess.

Flesch developed a test to rate how difficult a piece of writing would be to comprehend. We call this the Flesch Reading-Ease Test. Three factors determine the test’s score; total sentences, total words, and total syllables. The complexity of the words involved doesn’t matter. As they’re both two-syllable words, “kitten” and “amok” would have the same impact.

(My apologies if you suffer nightmares of kittens running amok because of this. Not my intention.)

Scores usually look like percentages, but the scale has no fixed limits. Some work by Dr. Suess can score higher than 120, while one sentence by Marcel Proust scores below -500.

Subject matter counts

Light-hearted fair tends to score easier. Reader’s Digest averages around 65 while Time gets a 52. An issue of The Harvard Law Review usually gets in the low 30s.

A review of 2,000 Wikipedia articles shows a similar trend. Pages about sports pros and musicians score in the 50s. Meanwhile, pages about scientists and philosophers come in in the 40s.

This is because technical jargon bloats your writing, making it harder to read. The same goes for most Latin terminology (sorry, biologists) and legalese.

With this in mind, take special care when writing about technical matters. When every syllable counts, words like “epidemiologist” have to be earned. Even if you’re writing for a university-educated audience, clarity is still important.

Enough about scores, let’s talk about grades

Flesch later worked with J. Peter Kincaid on the Flesch–Kincaid Readability Test. Developed for the U.S. Navy, the test looks at the same criteria — sentences, words and syllables. A grade is assigned to show the reading level required. Ever hear someone say their toddler’s reading at a grade four level? This is what they’re talking about.

The test was designed to line up with American public school grade levels. But as with the Reading-Ease test, there are no real limits. Dr. Suess’s Green Eggs and Ham is grade level -1.3. And that Proust sentence? Grade 39.1.

A different approach to building word power

Some authors always suggest aspiring writers build their word power. Learn all the obscure words you can so you can use insanely precise language when you write. You’ll never need an adverb again.

I’ve never understood this thinking. Rare words don’t make writing better. In fact, they make it suck. Period.

I’m going to say this once. Writing is the closest thing we have to real magic. As readers, we volunteer to be mesmerized, letting the writer weave their spell around us. Binding us to their will. It’s a completely immersive experience that dangles by a single, slender thread.

By making me put down a story to find a word in the dictionary, the spell is broken. All so the writer could show off with a word like “rachitic.” Way to go, Cormac McCarthy.

But seriously, wouldn’t it be better if you could just get lost in the words and not get kicked out by the writer?

Maybe we should redefine what word power is all about. To hell with obscure words! The new word power should be about stating complex thoughts in simple sentences. Sentences almost anyone can understand.

How can I measure and improve my readability?

There are a few tools at your disposal. You may have some of them already.

Microsoft Word can do it for you, but they make it hard. For starters, it’s turned off by default. To turn it on, go to File/Options/Proofing in the menu. Then, under When correcting spelling and grammar in Word, check Show readability statistics.

You’ll now see a readability report when you run a spelling and grammar check. But you have to muddle through the whole spellcheck process before you get to see it. You’ll get a pop-up screen showing your score and grade so you can think about what needs improvement.

There are also two freeware options I can recommend; Hemingway Editor and ProWritingAid. Both apps target your problem areas and show you exactly which sentences need to be fixed. That’s something Word can’t do.

Whichever one you choose to go with is a matter of personal preference. I go back and forth between them myself. But I tend to favor Hemingway Editor. Its interface is simpler. ProWritingAid definitely has more features. But that alone makes it easier to get lost in the process. Too many distractions for my taste.

Mind you, Hemingway Editor is tighter about what it defines as a long sentence. If you need a little wiggle room in your ramble, then maybe ProWritingAid is for you.

Quick tips for better readability

  1. Use short words whenever possible.
  2. State your thoughts as simply as you can.
  3. Keep your sentences short. How short? Real short!
  4. Keep sentence structures straightforward. Subject, predicate. Repeat. Follow Mr. Morton for guidance if you need it.
  5. Avoid subordinate clauses.
  6. Never use nested subordinate clauses.
  7. If you don’t know what a subordinate clause is, don’t ask me to clarify. You’re better off not knowing. Hopefully, you aren’t using them and don’t have anything to worry about.
  8. Use software to measure your readability and try to keep your writing below a grade 9 level. (According to Hemingway Editor, this article’s readability is grade 5.)

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