A common writing error is the improper use of double negatives. Examples of double negatives include:
“I haven’t got no money.”
“He is not going nowhere.”
And, courtesy of Pink Floyd:
“We don’t need no education.”
Here is what you need to know about double negatives and why you shouldn’t never . . . uh, shouldn’t ever use them.
We will get this out of the way right now: There are times when the use of double negatives may be correct. For example, saying, “Carla is not unattractive,” means that Carla is attractive. Assuming that Carla is, in fact, not hideous in appearance, this is correct. However, even though it is correct, it is confusing. Readers or listeners have to parse the sentence to get the meaning you intend. If you simply say, “Carla is attractive,” the meaning is much clearer. Typically, the use of a double negative in a context such as this is to “damn with faint praise.” Meaning, that I do not want to go so far as to say that Carla is attractive but, well, she is not unattractive.
Most of the time, though, people using double negatives do so incorrectly. As a result, they convey exactly the opposite of what they mean. You may remember from math class that two negatives equal a positive. The same is true in writing. If you break down what is being said in each of the example sentences above, it may be the opposite of what the writer or speaker intended. For example, if you don’t need no education, that means you do need some education. If he is not going nowhere, then he is going somewhere.
Not only do double negatives change the meaning of your sentences, they are among the most grating of errors. The use of double negatives marks you as an unskilled writer. Here are some examples of sentences you would not want to use in your mystery shop reports.
“The salesperson was not doing nothing.”
If the salesperson was not doing nothing, what was he doing? What you may actually mean is, “The salesperson was not doing anything,” meaning that the salesperson was not helping customers, or stocking shelves or any other activity.
“I did not see the server nowhere in the dining room.”
The correct way to say this is, “I did not see the server anywhere in the dining room.”
“Jason asked why I was returning the towels, and I said I did not need none of them.”
This could be written as, “Jason asked why I was returning the towels, and I said I did not need any of them.”
At best, using double negatives makes your meaning unclear or hard to discern. At worst, you will present yourself as a poor writer who lacks basic grammar skills. In general, they should be avoided in your writing.