The first article I submitted to DWT was on the error of writing it’s for its.
I was too late. Michael (It’s or Its?) had beaten me to it.
No doubt about it — the error of writing it’s for its is on everybody’s list of top ten errors that damage a writer’s credibility.
So why do so many of us keep making this error in our drafts?
As well as I know the rule, as many times as I have corrected the error in the manuscripts of others, the occasional it’s for its creeps into my own writing and must be caught in the final revision.
Why do we do it?
Because our subconscious mind tells us that the spelling it’s as a possessive is not “un-English” in the way that other errors are.
We write the house’s roof, so why not write it’s roof? The error it’s for its is the result of an instinctive mirroring of the possessive apostrophe s we use to form the possessive of nouns.
Here’s the kicker: when the third person neuter possessive adjective came into the language in the 16th century, it was spelled it’s for the very reason that the new form was modeled on the ‘s of the possessive noun. The spelling it’s for the possessive adjective was acceptable “down to about 1800” (A.C. Baugh, A History of the English Language, p. 295).
Nowadays, however, to write it’s roof instead of its roof marks a writer as pitiably ignorant of the rules of punctuation and orthography.
I’m not suggesting for a minute that we throw the rule out the window. It’s too firmly established for us to disregard it. All I wish to point out is that the error–while a mark of carelessness if permitted to escape the final revision of your manuscript–is the result of linguistic instinct, not obstinacy.
Moral: Rules of behavior are often arbitrary, like driving on the right side of the road in a given country. Arbitrary or not, we ignore them at our peril.