Q: I used to know the difference between “affect” and “effect,” but I’m not sure anymore. I often find them used interchangeably or in ways that I once thought were incorrect. Can you help?
A: Pat has discussed the distinction between “affect” and “effect” during her appearances on WNYC, but we find to our surprise that we’ve never written about it on the blog.
Let’s begin with an excerpt from the new third edition of Pat’s grammar and usage book Woe Is I:
“AFFECT/EFFECT: If you mean a thing (a noun), ninety-nine times out of a hundred you mean effect. The termites had a startling effect on the piano. If you want an action word (a verb), the odds are just as good that you want affect. The problem affected Lucia’s recital.
“NOTE: Then there’s that one time out of a hundred. Here are the less common meanings for each of these words:
“Affect, when used as a noun (pronounced with the accent on the first syllable), is a psychological term for ‘feeling.’ Termites display a lack of affect.
“Effect, when used as a verb, means ‘achieve’ or ‘bring about.’ An exterminator effected their removal.”
In addition, the verb “affect” can be used in the sense of to put on a false show (“He affected a British accent”) or to show a liking for (“She affects flashy clothing”).
With all these meanings, it’s no surprise that people have been confused by “affect” and “effect” since the various usages of these words showed up in English in the 14th, 15th, and 16th centuries.
“All this history of befuddlement has left us with a fat collection of warning notices,” says Merriam-Webster’s Dictionary of English Usage, which adds that nearly every usage handbook published in the 20th century had such warnings.
Most published writers know how to use these words, according to Merriam-Webster’s, but errors get into print because of “inattention to spelling,” “poor proofreading,” or “no proofreading.”
As an example of such a typo, M-W cites a comment by the former NBA player Darryl Dawkins about the impact on his flashy playing style of having therapeutic electrodes attached to his shoulder during a game.
Although Dawkins used the verb “affect” correctly (to have an impact on something), it appeared this way in a carelessly edited wire-service report: “It effected my interplanetary funksmanship.”
Our advice: When you use these words, especially when you’re in a hurry to finish an email, take another look before hitting Send.