You may have been taught that affect is a verb and effect is a noun—and so may the folks who created your grammar checker. For example, Google will underline “affect” in blue—its marker for “words that are deemed to be grammatical flubs” (Lanaria)—if you paste this sentence by Adam Gopnik into a Gmail message:
It was a family tease, and, like all family teases, was well-meaning in its affect and sharp-edged in its effect.
Yet the sentence employs both affect and effect correctly as nouns. Gopnik is using affect in the sense Merriam-Webster describes as “a set of observable manifestations of an experienced emotion: the facial expressions, gestures, postures, vocal intonations, etc., that typically accompany an emotion” (“Affect”). The “family tease” appeared well-intended, but its power (see “Effect”) was felt keenly.
By labeling this definition of affect “psychology,” the dictionary indicates that its use is specialized. “In ordinary usage,” however, according to Bryan Garner, “affect is always a verb; it means ‘to influence; to have an effect on.’ Effect, as suggested by its use in that definition, is primarily a noun meaning ‘result’ or ‘consequence.’ To affect something is to have an effect on it” (26). Yet this rule, which is widely taught to help students differentiate between the two words, is not comprehensive. Garner adds, “But as a verb, effect means ‘to bring about; produce’” (26). Claire Cook offers an example in which both words are used correctly as verbs:
The new wage offer affected our willingness to compromise on other issues, and we were able to effect a settlement within a few hours. (165)
Confusion over the correct use of the verb effect shows up frequently in discourse about “effecting change.” Effect, rather than affect, is correct because the phrase refers to creating, not influencing, change.
It may help to remember that to effect something is to bring it into existence; to affect something is to influence something that already exists. For example, “How can I affect the outcome?” means, “How can I influence the outcome?” The existence of the outcome is presumed. “How can I effect the outcome I desire?” means, “How can I create a specific outcome?” The outcome in question may not occur if the speaker doesn’t effect it.
“Affect,” N. (1a). Merriam-Webster Unabridged, 2022, unabridged.merriam-webster.com/collegiate/affect.
Cook, Claire Kehrwald. Line by Line: How to Edit Your Own Writing. Houghton Mifflin Harcourt, 1985.
“Effect,” N. (4). Merriam-Webster Unabridged, 2022, unabridged.merriam-webster.com/collegiate/effect.
Garner, Bryan A. Garner’s Modern American Usage. Oxford UP, 2003.
Gopnik, Adam. “How Florine Stettheimer Captured the Luxury and Ecstasy of New York.” The New Yorker, 21 Feb. 2022, newyorker.com/magazine/2022/02/28/florine-stettheimer-artist-book-review-barbara-bloemink.
Lanaria, Vincent. “Gmail Will Help You Write Grammatically Correct Emails with Artificial Intelligence Soon.” Tech Times, 20 Aug. 2019, techtimes.com/articles/245070/20190820/gmail-will-help-you-write-grammatically-correct-emails-with-artificial-intelligence-soon.htm.