We need not suffer this affective disorder
After seeing “affect” used improperly several times in succession years ago, I photocopied the “AP Stylebook” entry, cut it out, copied it at 200 percent, then doubled its size again, knowingly contributing to deforestation and exacerbating profit declines for the Newhouse family.
Unfortunately, the small act of posting the enlarged affect/effect entry on my desk divider failed to put the issue to a rest. At some point AP updated its entry. It’s now less succinct, but it’s still a good guide. There are many good explanations out there of the correct usage (see a few below), but affect/effect mixups remain a common usage annoyance.
A copy editor friend recently suggested I blog about it. His suggestion came on the heels of another copy editor’s call for help after her brain seized up on the matter.