Polite social society is comprised of many things that most of us are taught from a very young age. Erard uses examples of characters in litterature and plays, such as Richard Brinsley Sheridan's, The Rivals to demonstrate what a fool one can make of ones self when attempting to appear more intelligent then they actually are. The very term Malaprop, a french trerm (mal a propos) meaning innapropriate, was popularized by such a fictional character, Mrs. Malaprop.
These types of slips are characterized by the use of similar sounding word, with a sometimes extremely different meaning than what was intended. This error is based entirely on sound similarities, and has nothing to do with meaning, resulting in a selection that is still a word. These errors are most often made by people that are overreaching their position, social class, or level of education; they are typically considered slips of the tongue. The formation of "folk etymologies" can easily lead to malaprops where a word or phrase was misheard once and continues to be used because the speaker has convinced themselves it is correct. This type of error is known as an eggcorn, which is a mistake itself of the word acorn. Eggcorns differ between people, families, and social circles; and also in that they maintain most of their meaning and make some sense. Do you have any words or phrases that you repedetly make mistakes with? Where did these errors come from?
With the advent of communication technologies such as text messaging and AIM, we all find ourselves shortening and misspelling words for speed and connivence. I often find myself carrying this practice over into my professional speaking and writing. Are we simply setting ourselves up for a new era of malaprops and eggcorns that haven't existed in the past?
If these errors of misuse are evident to educated people, what keeps them from correcting the speaker? Is it polite instinct that tells the listener to bite thier tongue, or is it uncertainty about the correctness of their accusation? What is to come of our language if malaprops and eggcorns are allowed to persist uncorrected? What if the person doing the correcting is inncorrect?
How might these language tendencies help or hurt a non-native English learner?
Check out the Eggcorn Database, which contains nearly 600 example of eggcorns.
(link is currently down, will be up soon... http://eggcorns.lascribe.net)