Making comparisons can add strength to any written text. You can use comparisons to illicit an emotional response in your reader, to illustrate a concept more clearly, or even as evidence for your claims. It’s important to make your comparisons effective ones, because a bad comparison can derail an entire text. There are two main types of bad metaphors. In the first, the metaphor is too sprawling or too confusing to work effectively. In the second, the metaphor can be fallacious, with major relevant differences between the two things being compared. For example, take the following metaphor:
Guns are like hammers. They’re both tools with metal parts that can be used to kill someone. It would be ridiculous to restrict the purchase of hammers. Therefore, it is equally ridiculous to restrict the purchase of guns.
Most people realize this is a bad metaphor, but do you know why? Nothing here is incorrect, after all. The metaphor is comparing two things that do have common characteristics. But that isn’t all that’s necessary for a good, convincing metaphor. When you compare two things, you have to make sure that you’re not ignoring any relevant differences between those things. Let’s take a look at the differences guns and hammers:
Guns are a different shape than hammers; their “handle” is much shorter. Their purpose is different; guns are designed to do bodily harm and/or cause death, while hammers are designed to aid with building. Guns have removable parts and hammers don’t. When used for violence, a gun is much faster and more efficient at killing from a range; a hammer takes longer and requires close contact.
Now think again about the argument being made: We shouldn’t regulate the sale of guns. Are any of these differences between hammers and guns relevant to that argument?
Yes, of course. Two of the differences, relating to purpose and efficiency in violence, are relevant. The other two differences, regarding the shapes and removable parts, are not relevant. This is because the regulation of guns is justified by their killing power and purpose, not because they have short handles or removable parts. If those were the only differences between hammers and guns, then this metaphor would be very convincing.
When you think about the regulations we have on weapons, their efficiency at killing lots of people very quickly is a huge factor in how much regulation we usually legislate. The most efficient killer is something like a nuclear bomb. If you were to go out looking for the parts to build one of those, you’d have a very difficult time of it, since the sale of the most important materials is outright banned for citizens. Below that we have more mundane bombs, and the sale of certain materials used to make bombs are also heavily regulated. Even when we look at gun laws, most people pushing for regulation would like heavier regulation on more efficient guns than the less efficient ones. People aren’t really that concerned, for example, with heavily regulating the sale and use of 19th-century rifles, because they just aren’t that great at killing people. Less efficient weapons, like knives, are either not regulated at all or only lightly regulated. There’s a logic behind this: the more people you could kill the fastest with it, the less people we want to have unfettered access to that weapon.
Now, this bad metaphor doesn’t mean that the conclusion is entirely wrong. It does mean that it is a poor argument and that the metaphor is ineffective. If this writer wanted to convince someone that gun regulations are ridiculous, he will simply not succeed in doing so. Good metaphors have two (or more) things compared that are alike in all aspects relevant to the argument or illustration.
Here are some examples of this common writing weakness:
The American public is a servant to the whims of the media, and while the media is a dog who sees a squirrel every five seconds, there is always one squirrel bigger than the rest that it keeps chasing. In the mid-200’s that squirrel was the Iraq war. In this metaphor, the media is a dog and the stories are squirrels. But why are we comparing those things? What characteristics does a news story or war have in common with a squirrel? This metaphor is confusing and doesn’t make a lot of sense. The question you want to ask yourself is, “Does this make my point more clear?” The answer with this comparison is a resounding “no.”
Having tattoos is just like slavery but not as bad. This one, without context, is literally incomprehensible. The reason is that tattoos and slavery do not have any remotely obvious common characteristics. This is also a bad metaphor because comparing something as brutal and inhumane as slavery to something mundane and everyday is usually pretty offensive.
College is a business, so it should be run like one. Students are customers and professors are their employees. It’s their job to make their students happy. This is a very common metaphor made about education. And it’s convincing to some people because there are certainly similarities between students and customers, and professors are providing a service in exchange for money. However, this metaphor has the same problem the gun one did; it ignores a key relevant difference between the two that undermines its conclusion. That difference is the goals of a business versus a college. A business’s purpose is to produce profit. But colleges are not meant to just pump out money and a product (degrees); their purpose is to provide education to the public. This difference is relevant because when a professor’s job is to educate, not to please, they simply cannot be treated as an employee of the student. This metaphor falls apart when you consider the different purpose and goals of a business vs. a university.
So how can you determine if your own metaphors are good are bad? After your draft, circle all the comparisons you made and read them aloud. Does the comparison make sense? Is it simple enough to understand? Does it make the concept easier to understand or more difficult?
Write down the ways in which the two things are alike and not alike. Make sure that everything in the “not alike” column is not relevant to your argument, conclusion, or illustration. If you can’t think of a good metaphor, it’s not the only way to explain something! Don’t beat a dead horse, and find a different way to convey what you mean.
Return to Common Writing Weaknesses.
Written by Courtney Stoker