A user on Twitter asked me recently about the difference between "affect" and "effect." Specifically, she wanted to know which to use in the phrase "the affect/effect of celebrity endorsements."
The difference between "affect" and "effect" is Grammar 101. It's one of the first things any aspiring copy editor is sure to note. And it's something I've written about so many times I'm always surprised when people have to ask about it.
So naturally, I answered the question wrong. In a moment of haste, I glossed right over the words "the" and "of," instead reading the example as something like "Such and such will affect celebrity endorsements."
Had that been her question, my answer would have been right. Unfortunately, the words "the" and "of" in the phrase "the effect of celebrity endorsements" make all the difference in the world, rendering this a passage clearly in need of a noun. Yet I told her to use the verb "affect."
There's an important lesson in here about carelessness. Unfortunately, I may be more in need of that lesson than anyone reading this. But here it is anyway: When you're minding your p's and q's, mind your p's and q's. A great many language errors are born not of ignorance but of haste. Those can be a crying shame for anyone who took the time to learn a language rule but nonetheless gets it wrong, especially if she gets it wrong in a public forum.
Of course, slow, cautious reading and writing aren't the only ingredients for proper use of "affect" and "effect." You have to know the difference, too.
In most cases, the difference is simple. "Affect" is a verb, and "effect" is a noun. So if you're using it as an action, as in "Caffeine doesn't affect me," you usually want the one that begins with A. If you're treating it as a thing, as in "Caffeine has a bad effect on me," you usually want the one that begins with an e.
To remember this, I used to think of the term "side effect," which is clearly a noun, and I would note that the E at the end of "side" prompts me to use an E to start the next word as well.
"Affect" and "effect" are usually simple. But, like many things in language, there's a twist. Luckily, it's rare and hardly ever comes up in casual writing. If you're still on shaky ground with "affect" and "effect," you might want to just think of the former as a verb and the latter as a noun and leave it at that. But if you can handle a wrench thrown into the works, here it is: Sometimes "effect" is a verb and sometimes "affect" is a noun.
The form of "effect" that's a verb seldom comes up in casual conversation. You hear it more in formal contexts like academia and government in sentences like "This new policy will effect positive change." See how "effect" is working as a verb here? The verb form of the word "effect" means to cause something or to make something happen.
The noun form of "affect" is even rarer. It comes up mostly in contexts that have to do with psychology, such as "Patients showed perfectly normal reactions and affects." Here's how Merriam-Webster defines this form of affect: "the conscious subjective aspect of an emotion considered apart from bodily changes" or "a set of observable manifestations of a subjectively experienced emotion."
Again, those are rare. In most cases, the difference between affect and effect is the simple difference between nouns and verbs. But to get them right, it also helps to be awake.
June Casagrande is the author of "The Best Punctuation Book, Period." She can be reached at JuneTCN@aol.com.