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Illogical Comparisons: “It’s raining cats and oranges out there!”

Alright – if Misplaced Modifiers are my favorite SAT grammar topic, Illogical Comparisons must come in a very, very close second.

Like Misplaced Modifiers, Illogical Comparisons can lead to some humorous situations in a test that’s way too straight-laced. I also like this error because it’s very simple to catch and shows up on every test, sometimes more than once – you just have to get in the habit of looking for it.

We get away with making this grammar error in common speech because most people will understand what you mean, but the SAT is extremely picky about it (also read Why is Grammar Important?).

The idea behind this topic is that, when any sort of comparison is made between two or more things, those things must be of the same “type” or “category,” and should be in as similar a form as possible.

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It’s easier to demonstrate than to explain, so here are some things that CAN be compared, according to the SAT:

Cats vs. Dogs (they are both animals)

Apples vs. Oranges (they are both fruit)

Firemen vs. Policemen (they are both professions/types of people)

Speed of a car vs. speed of a motorcycle

Now, here are some things that could NOT be compared properly, according to the SAT:

Cat hair vs. Dogs (we can’t compare “hair” to an animal like a “dog”; it’s not a logical or “fair” comparison to make; change it to cat hair vs. dog hair)

Apples vs. Orange Trees (one is the fruit, the other is the tree it grows on)

Firemen’s salaries vs. Policemen (one is money, the other is a person/profession)

A car vs. speed of a motorcycle

You also want the forms of the words to match as closely as possible – this is a concept that is primarily covered by Parallelism rules, but I see them as related.

Here are two examples of what happens when this similar-form rule of thumb is broken in comparisons:

BAD Comparison/Parallel Form: I like to run more than jumping. (Wrong because of different verb forms; fix by using “running” instead)

BAD Comparison/Parallel Form: It is better to love than being loved. (Wrong because of different verb forms; fix either as “Loving is better than being loved,” or “It is better to love than to be loved.”)

Here’s one really tricky variation on illogical comparisons that the SAT Writing test sometimes uses: Does the following sentence sound wrong to you?

“The length of this train is more incredible than any bus I’ve ever seen.”

Well, it doesn’t sound wrong to me. But it is wrong. Take a look at exactly what’s being compared: “Length of this train” vs. “Any bus.”

It’s illogical to compare a “length” to a “vehicle.” Fix the sentence by adding “…the length of any bus…”

As you train yourself to notice this error every time, one thing you need to watch out for on the SAT is any kind of “comparing” word; this can range from “more ___” to “bigger,” “wiser,” “darker”…

However, the single biggest giveaway that this Illogical Comparison error might be under your nose is the word “than,” which always indicates a comparison. It won’t be there 100% of the time, but pretty darn close.

To get the complete text of this SAT Grammar lesson, along with more than 14 other lessons, two diagnostic tests and over two hundred SAT Writing practice questions, purchase your copy of The Top 12 SAT Writing Grammar Rules today!

Further Reading:
What exactly is on the SAT Writing section?
SAT Writing Rules: Misplaced Modifiers
SAT Writing Rules: Parallelism
Why is Grammar Important?

Additional Resources:
SAT Grammar Crammer: The Top 12 SAT Writing Rules

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