This month, quite by coincidence, I’ve been reading three books written by men who are all well past retirement age. Experience has taught them to write concisely about big topics, a skill that no writer ever really perfects.

In “The Meaning of Human Existence,” 85-year-old scientist Edward O. Wilson discusses what he’s learned about why we’re here and where we’re going. He says what he has to say about life’s most profound question in 204 pages.

In an even slimmer book called “Essays After Eighty,” 86-year-old Donald Hall describes what it’s like to be really old.

Roger Rosenblatt, who’s over 70, uses 175 pages in “The Book of Love” to consider affection of all kinds — romantic love, love of country, love of work.

Wilson’s book is already in bookstores. Hall’s and Rosenblatt’s books haven’t been released yet, but advance copies crossed my desk.

I mention the age of these authors because we often assume that people get more long-winded as they grow older. These writers, though, say a lot with a few words.

As a newspaper editor, I must often ask writers to shorten their work, a message that no one likes to hear. Brevity isn’t everything, I’ll grant you. In a world where all things must be brief, we’d have no “War and Peace,” no Shakespeare, no Bible. Even so, we can often express a great deal in a small space. These books by Wilson, Hall and Rosenblatt remind me that this is so.

In “Essays After Eighty,” Hall tells readers that writing frequently involves revision. In refining his work, Hall usually learns ways to make it shorter, not longer.

“There are problems in writing one can learn to avoid,” he says. “Almost always, in my poems or essays, the end goes on too long. ‘In case you didn’t get it, this is what I just said.’ Cut it out. Let the words flash a conclusion, then get out of the way.”

In one memorable sentence, Hall sums up how a year looks from his living room window: “Out the window, I watch a white landscape that turns pale green, dark green, yellow and red, brown under bare branches, until snow falls again.” Using just 25 words, Hall aptly describes the passage of 365 days. Even lean language can contain multitudes.

A friend recently shared a story, perhaps true, of a colonial hat maker who initially ordered a 10-word sign for his shop, but eventually reduced it to a simple picture of a hat with his name underneath — enough to tell his customers who he was and what he sold.

Writing briefly takes practice, and there’s always room for improvement. Earlier this year, for a New York Times blog about writing, I wrote an essay about the virtue of brevity. Comments poured in from across the country.

A few readers said they liked my essay about brevity, although they suggested that it could have been shorter …

Danny Heitman is on Twitter, @Danny_Heitman.