Read the following sentence.
“But my neighbor refuted the idea that she could not disregard the least amount of dust.”
Did you need to read that more than once to figure out what it means? The sentence contains several negative words which take more work to decipher than positive words.
Sentences like this one are common. “A stay of execution has been denied.” (Two negatives) “That is not an insignificant barrier to success.” (Two negatives, or three if you think of “barrier” as a negative) “If seldom eaten, a candy bar is not injurious to our health.” (Three negatives)
As students, we are taught that a double negative equals a positive. We are aware of “not,” “never,” and “no” as negatives. But many other words with negative connotations can confuse listeners and readers. Some are
Ain’t, although, any, avoid, barely, but, deny, doubt, few, hardly, however, ignore, instead, least, little, neither, nobody, none, nothing, nowhere, rarely, refute, scarcely, seldom, and though.
Thousands of other negatives can be formed by adding the prefixes “dis-,” “‘il-,” “im-,” “in-,” “ir-,” and “un-” to words, as in disregard, illegal, immoderate, inverse, irrefutable and unlikely.
Adding to the confusion, in some languages and in some dialects of English, double negatives are acceptable to add emphasis. But not in standard English.
So, if you want your readers to understand you at the first read, write using positives, not negatives.
By the way, that first sentence means that my neighbor said he or she could ignore a small amount of dust.