Another language change that has already begun and may be inevitable is the use of “tact” instead of “tack,” in the phrase try another tack. When young people favor a particular usage, the older form is in danger. But sometimes the older form hangs on and outlives the fashion, if it is preserved among the educated. Yet if even the educated young people use the new form, unaware that an older form with understandable meaning even exists, I consider the game lost. I am hearing the new usage from medical students and residents. This is how language has changed since it was first created, a new form supplanting the old, for good reasons or bad. It doesn’t much matter if it’s wrong.
“Tact” has an additional advantage in that it makes a sort of sense. Trying a different approach with a person is one strategy of being tactful, so there is nothing in taking a different tact to make the mind rebel. Not that the mind does rebel in such matters very often, even when what comes out of our mouths is odd, would we but look at it. Idioms are so common in every language that we just swallow them whole, for the most part. (For example, look at the very phrase I just used, for the most part. It is an archaic usage preserved in that phrase and few other places. Or, my use of the word “very” in that sense two sentences ago – an oddity, more related to the creedal phrase “Very God of Very God” than to the modern common usage as an intensifier.)
In this case, the older form may yet win the day if more young people take up sailing.
For those to whom this claim that “tack” should still be regarded as more correct is new, the word comes from sailing. You tack into the wind when the place you are trying to get to is upwind. If your destination is north, and the wind is coming from the north, you can’t sail directly into it – you would be pushed back. But you can sail NW for a bit, then “come about,” switching the sail to the other side of the boat, and sail NE. Zigzagging forward in this way, you can go north. At the NW point where you feel you have gotten about as much benefit as you can from that tack, and are now losing more to the destination than you are gaining, you take a different tack and cross back to the NE. “Tact” has nothing to do with it.
Nor are the words related at their roots. “Tact” is from Latin tactus, to touch or feel, used in a metaphorical sense in English of a person who can sense what is needed. “Tack” is probably related to the various uses of small or temporary attachment: carpet tack, sticky tacki-ness. One such temporary fix was a rope tied to the corner of a sail to hold it in place.