Several of my current or recent jobs involve a fair amount of fact-checking, so I’m feeling both heroic about the errors and inconsistencies I’ve caught and anxious about the ones I know for absolute sure I’m missing.

You know how it goes: You’re reading along in a pretty good book and you screech to a halt at something that’s flat-out wrong. Not a typo or a misplaced modifier or a grammatical goof: a genuine error of fact. Maybe you know the right answer because it’s about your hometown, the car you drive, a subject you’ve been studying for years, or the work you do for a living.

“Where was the editor?” you cry. “Any idiot knows that’s not right.”

The editor and the proofreader would probably be mortified to learn that this error had slipped through. The more significant the error, the more mortified they’d be. At the same time, it’s ultimately the author’s job to get it right, so let’s not be blaming it all on the poor editor — not least because the reader of a published book has no way of knowing how many errors and inconsistencies the editor and proofreader caught.

Pick up a good book, fiction or nonfiction, and read a few pages. Notice how many matters of fact there are, how many opportunities there are to get something wrong or not quite right?

As an editor I don’t do the kind of rigorous fact-checking done by good journalists and others, where everything that isn’t common knowledge (like the law of gravity) has to be confirmed by at least two independent sources. “Fact-checking” is a task in its own right. It overlaps copyediting, but it’s not the same.

I do routinely check the spellings of place and personal names, especially when I’m not familiar with them. I’m currently editing a book about an eminent classical musician of the last century. This isn’t a field I know well, so I’m looking almost everything up. This is how I learned that Goosens was supposed to be Goossens and something else: that three successive generations of this musical family included a Eugene. The elder two spelled their first name Eugène but the youngest had dropped the accent. I couldn’t tell for sure which Eugene/Eugène Goossens was being referred to, so I asked the author. The youngest, she informed me. “Eugene” it was.

I’m also proofreading a long nonfiction book with many, many names, dates, and other details. This is a “cold read,” which means that though I do have access to the copyedited manuscript, I am not reading the proofs against it. When a book’s been competently edited and copyedited, errors and inconsistencies are generally few and relatively minor, but they are there. I was quite pleased with myself when I realized that a fellow who was survived by eight children when he died on September 13 had been the father of nine on September 9.

What did I do next? From context I knew that there was virtually no chance that a child had died between the 9th and the 13th; in other words, this was an error. Because  this fellow was not famous and the number of children he had was irrelevant to the story, I didn’t even think to look it up. (Fact-checking in the digital age can be a terrible time sink. There are a helluva lot of fascinating facts out there.) I noted the discrepancy on the proofs and left it to the author to deal with.

Reading the same proofs, I came to a sentence that ended with a series of organization names: “the House of Representatives, the New York Urban League, the National Legal Aid, the Defender Association, and the Buffalo Council of Churches.” “The National Legal Aid” looked odd. What was the “the” doing there? So I looked it up — and discovered that “the National Legal Aid” and “the Defender Association” were not two organizations but one: the National Legal Aid and Defender Association (NLADA). Which of course I had to read up on — see what I mean about time sinks?

This is what’s known in the trade as a “good catch.” I’m still feeling a little smug about it.

How about when an error goes beyond an easily verifiable fact? Some things we catch because we have knowledge of the subject matter. Editors bring their personal histories as well as their editorial experience to each new job, so we’ll catch things in the areas we know well and speed on by things in areas we don’t.

Checking street maps to make sure a driver can make a left turn from Street A onto Avenue B? Verifying appropriate technology in a historical novel, or customs in a place far from home? Basically it’s the author’s job to get this stuff right. When the editor, copyeditor, or proofreader catches an impossibility, an anachronism, or a cultural improbability, it’s great, but editors are not fact-checkers and we’re usually working on deadline.

An obvious gaffe can undermine a book’s credibility. Competent editing and proofreading will greatly reduce the number of errors, inconsistencies, and unclarities that slip through, but in this, as in everything else, perfection is not possible.

If you’re the writer, however, it’s your name in the byline or on the book cover. There’s a reason for that. You’re the one with the most power to get the facts right.