What journalists write when they encounter a known unknown.

For the purpose of an elegant finish to this piece, I wish that Nexis had revealed me as one of the guilty so I could humbly attack myself. I'm not so lucky. A handful of my Slate colleagues, however, lapsed in that direction. I am as filled with forgiveness for them as I am with relief for myself.

As journalistic ills go, this one is no cancer, but it's often a symptom of journalists who chased a story and didn't catch it.

******

Thanks to reader Ian Quigley for the idea. Maybe I missed my use of the phrases. Make me honest! Fire up your Google and your Nexis, and catch me in the act. Send your findings to slate.pressbox@gmail.com. For unknown unknowns, see my Twitter feed. (E-mail may be quoted by name in "The Fray," Slate's readers' forum; in a future article; or elsewhere unless the writer stipulates otherwise. Permanent disclosure: Slate is owned by the Washington Post Co.)

Track my errors: This hand-built RSS feed will ring every time Slate runs a "Press Box" correction. For e-mail notification of errors in this specific column, type the word unknowns in the subject head of an e-mail message, and send it to slate.pressbox@gmail.com.

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