Sweating the small stuff
Jan Freeman, writing at Throw Grammar From the Train, points out that it’s for its is a spelling error rather than a mark of ignorance or a moral failing. People, at least literate adult people, know the meanings of the two forms and simply make a mechanical error. Everyone does.
The slip is made easy because English uses the apostrophe to indicate both contraction and possession. In Anglo-Saxon, es was one of the suffixes indicating possession. As Middle English developed, es came to be used for all possessives, and, since the e was not pronounced, the apostrophe was introduced to indicate the omission.
The development has not been smooth sailing. Some writers thought erroneously that ’s was a contraction of his, so you have Sir Thomas Browne writing things like “Moses his man.” And before orthography became standardized in the nineteenth and twentieth centuries, you have Jane Austen writing her’s.
For today’s writers, as those busy fingers navigate along the keyboard at the brain’s direction, it is extremely easy for the pilot to blink and veer to the familiar pattern it’s rather than the equally familiar pattern its. The same thing happens with a lot of closely resembling pairs, such as then and than.
We're all susceptible to such slips, which look sloppy and require cleaning up to make a text presentable, but they are still minor errors, however annoying. They indicate that you are unkempt, not that you are illiterate.
Many of you have been kind enough to point out typos in these dispatches*—the other day I mistyped America in a headline, thanks to posting early in the morning, before coffee, while wearing the wrong glasses. That was embarrassing and a mark of haste and carelessness, but the reader who pointed it out did not assume that I was ignorant of the correct spelling.
Ignorant and incompetent writing abounds, so there is plenty about which to get huffy. But don’t spend your superiority on typos and trivial misspellings. Save it for the big things.
*Correcting a copy editor appears to be one of the profoundest satisfactions in life.