Metaphors — comparisons of one thing to another in a poetic sense — are not just for poetry: they are an integral part of language. Metaphors help us communicate an idea more clearly by making it more vivid, more relevant or less complicated. We use metaphors every day: whenever we compare sports to war, a corporate merger to a romance, a political campaign to a horse race.
Metaphors are a useful linguistic device, but sometimes they can go off the rails (a train metaphor). Writers sometimes get carried away (a nautical metaphor) and shift gears (an automotive metaphor) in the middle of a metaphor, which can befuddle readers instead of making an idea clearer to them.
A recent news story I saw said that my employer, the University of Kansas, “pushed ahead by a few nose lengths” in an annual college ranking. I’ll buy a horse-race comparison here (though this annual ratings scramble seems more aptly compared to a decathlon), but horses can win by a “nose,” or by a “length.” A “nose length” is not a distance used in horse racing, so instead of making the idea clearer, this metaphor confuses the issue. Plus, a ranking doesn’t really need a metaphor to make it more easily understood. “Moved up a few spots” would have been perfectly clear.
In my career as a copy editor, I’ve run across a lot of mixed or mangled metaphors. Some made me scratch my head (figuratively) and others made me laugh out loud (literally). Here are a few:
“When this critical column buckled due to lack of floor supports, it was the first domino in the chain.” Domino effect / links in a chain — pick one.
The rival teams “find themselves with their backs against the wall as if they were stuck in a linen closet.” The backs-against-the-wall part is clear (if a bit cliched), but how the heck does a linen closet enter into things?
“We’re just about ready to start putting the pieces of this puzzle together in a way we can put some real structure on this skeleton.” Is it a puzzle, or a building, or a skeleton?
“A lot of people think they were born on third base and hit a home run.” How this usually goes is “He was born on third base and thinks he hit a triple,” which is a sports metaphor applied to a person who comes from a privileged background but is oblivious to the fact he got a head start. How the home run connects here I can’t imagine.
“As you go in the belly of the beast, you will run into this brick wall every single time.” Since when are there brick walls inside beasts?
The reason to use a metaphor is to help readers understand something. If it doesn’t do that, it’s not working — and your best bet (a gambling metaphor) is to rewrite.