"When I use a word," Humpty Dumpty said, in a rather scornful tone, "it means just what I choose it to mean - nothing more nor less." "The question is," said Alice, "whether you can make words mean so many different things." Lewis Carroll
According to the Oxford English Dictionary, the 500 words used most in the English language each have an average of 23 different meanings. The word "round," for instance, has 70 distinctly different meanings. The variance of word meanings in natural language has always posed problems for those who attempt to construct an unambiguous and consistent statement. It is often the case that a written statement could be interpreted in several ways by different individuals, thus rendering the statement subjective rather than objective. The first detailed examination of this problem with respect to the specifications of computer systems is contained in [Hill, 72]. Hill provides a plethora of examples to illustrate this common problem. Peter G. Neumann illustrated this point by constructing a sentence which contained the restrictive qualifier "only." He then showed that by placing the word "only" in 15 different places in the sentence resulted in over 20 different interpretations [Neumann, 84]. Moreover, other words like "never," "should," "nothing," and "usually" are sometimes applied in a manner in which a double meaning can be ascribed. In particular, the word "nothing" was a favorite word often used by Lewis Carroll.
Occasionally the ambiguity found in natural language may evoke images of the ridiculous while at other times it may be the source of humor. The examples presented here point to the potential confusion that can result when using natural language. That is, informal descriptions are subject to the vagaries and ambiguities of the natural language in which they are expressed. Those who formulated these statements did not fully consider the implications caused by the way in which the sentences were phrased. In a sense, they became victims of the Humpty-Dumpty Syndrome, a phenomenon where individuals fail to realize that words have many meanings and that others may not always be able to surmise the intent of a particular statement.
If simple statements like those given on this Web page are vulnerable to ambiguity, one can only imagine the potential problems that exist within a software requirements specification (SRS) written entirely in natural language. Such documents can easily be hundreds or thousands of pages in length. The possibility of ambiguities and inconsistent statements existing in such documents is very real.
The following represents a collection of ambiguous or inconsistent statements that I have found from various places. While most of them provide a source of amusement, my overall goal is to show that the cavalier use of natural language can often lead to unintended meanings.
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Part 1: Lets face it, English is a stupid language. There is no egg in the eggplant. No ham in the hamburger. And neither pine nor apple in the pineapple. English muffins were not invented in England. French fries were not invented in France. We sometimes take English for granted. But if we examine its paradoxes-- We find that Quicksand takes you down slowly. Boxing rings are square. And a guinea pig is neither from Guinea nor is it a pig. If writers write, how come fingers don't fing. If the plural of tooth is teeth, shouldn't the plural of phone booth be phone beeth? If the teacher taught, Why didn't the preacher praught. If a vegetarian eats vegetables What does a humanitarian eat!? Why do people recite at a play Yet play at a recital? You have to marvel at the unique lunacy Of a language where a house can burn up as It burns down And you fill in a form By filling it out And a bell is only heard once it goes! English was invented by people, not computers And it reflects the creativity of the human race (Which of course isn't a race at all) That is why: When the stars are out they are visible But when the lights are out they are invisible And why it is that when I wind up my watch it starts but when I wind up this poem it ends?
Lexicon of Inconspicuously Ambiguous Recommendations (Ways to handle those tricky situations! ) You're called upon for an opinion of a friend who is extremely lazy. You don't want to lie --- but you also don't want to risk losing even a lazy friend. Try this line: "In my opinion," you say as sincerely as you can manage, "you will be very fortunate to get this person to work for you." This gem of double meaning is the creation of Robert Thornton, a professor of economics at Lehigh University in Bethlehem, PA. Thornton was frustrated about an occupational hazard for teachers, having to write letters of recommendation for people with dubious qualifications, so he put together an arsenal of statements that can be read two ways. He calls his collection the Lexicon of Inconspicuously Ambiguous Recommendations. Or LIAR, for short. LIAR may be used to offer a negative opinion of the personal qualities, work habits or motivation of the candidate while allowing the candidate to believe that it is high praise, Thornton explained last week. Some examples from LIAR To describe a person who is totally inept: I most enthusiastically recommend this candidate with no qualifications whatsoever. To describe an ex-employee who had problems getting along with fellow workers: I am pleased to say that this candidate is a former colleague of mine. To describe a candidate who is so unproductive that the job would be better left unfilled: I can assure you that no person would be better for the job. To describe a job applicant who is not worth further consideration: I would urge you to waste no time in making this candidate an offer of employment. To describe a person with lackluster credentials: All in all, I cannot say enough good things about this candidate or recommend him too highly. Thornton pointed out that LIAR is not only useful in preserving friendships, but it also can help avoid serious legal trouble in a time when laws have eroded the confidentiality of letters of recommendation. In most states, he noted, job applicants have the right to read the letters of recommendations and can even file suit against the writer if the contents are negative. When the writer uses LIAR, however, whether perceived correctly or not by the candidate, the phrases are virtually litigation-proof, Thornton said.
Date: Mon, 19 May 2003 12:08:19 -0600 (MDT)
Subject: (SEWORLD) ETAPS 2004: FIRST CALL FOR SUBMISSIONS
Please apologize if you receive multiple copies of this message.
The following is an ad from a real-life newspaper which appeared four days in a row - the last three hopelessly trying to correct the first day's mistake. MONDAY: For sale: R. D. Jones has one sewing machine for sale. Phone 948-0707 after 7 P.M.. and ask for Mrs. Kelly who lives with him cheap. TUESDAY: Notice: We regret having erred In R. D. Jones' ad yesterday. It should have read "One sewing machine for sale cheap. Phone 948-0707 and ask for Mrs. Kelly, who lives with him after 7 P.M." WEDNESDAY: Notice: R. D. Jones has informed us that he has received several annoying telephone calls because of the error we made in the classified ad yesterday. The ad stands correct as follows: "For sale -- R. D. Jones has one sewing machine for sale. Cheap. Phone 948-0707 after 7 P.M. and ask for Mrs. Kelly who loves with him." THURSDAY: Notice: I, R. D. Jones, have no sewing machine for sale. I intentionally broke it. Don't call 948-0707 as I have had the phone disconnected. I have not been carrying on with Mrs. Kelly. Until yesterday she was my housekeeper, but she has now quit.
Philip Morris' Bible gets $12.8 mln in 1999WASHINGTON, March 10 (Reuters) - Geoffrey Bible, chairman and chief executive of the world's largest tobacco company Philip Morris Cos. Inc.
The other day a friend of mine got into some trouble with the authorities. It seems he'd parked his car in a restricted area. But he saw a cop putting a ticket on it, and complained so vociferously that he got hauled in front of the local law. It didn't get much better from there. He insisted on explaining things to the judge at some length, I'm afraid. And what did he say? Well, over and over again, he just kept repeating, "But the sign clearly said: Fine for parking here!'"
The Cuisine of India is a restaurant that I eat at frequently for lunch (they are in the same building as the computer science department). I was surprised to be watching Jay Leno one evening when he did his Monday night "Headlines" feature and mentioned this restaurant. In the Tennessean, they had placed an ad that read: "Cuisine of India: Nashville's Finest Italian Restaurant" Next time I go there I will ask for some tortellini...
Following the tragic JFK Jr. accident, Reuters reported: Thursday July 22 9:22 AM ET (Reuters) "Kennedys Board Cutter On Way To Sea Burial" The story was corrected so that a "kitchen board cutter" could not be inferred: Thursday July 22 10:15 AM ET (Reuters) Kennedys Board Ship To Scatter JFK Jr.'s Ashes
Here are some sentences from actual newspaper articles: o Great care must be exercised in tying horses to trees, as they are apt to bark. o We do not tear your clothing with machinery; we do it carefully by hand. o After Governor Baldridge watched the lion perform, he was taken to Main Street and fed twenty-five pounds of red meat in front of the Fox Theater. o Dr. Benjamin Porter visited the school yesterday and lectured on "Destructive Pests". A large number were present. o The Duchess handled the launching beautifully, confidently smashing the champagne against the prow. The crowd cheered as she majestically slid down the greasy runway into the sea. o Anti-nuclear protestors released live cockroaches inside the White House Friday, and these were arrested when they left and blocked a security gate.
Spell Checker Eye halve a spelling chequer It came with my pea sea It plainly marques for my revue Miss steaks eye kin knot sea. Eye strike a key and type a word And weight four it two say Weather eye am wrong oar write It shows me strait a weigh. As swoon as a mist ache is maid It nose bee fore two long And eye can put the error rite Its rare lea ever wrong. Eye have run this poem threw it I am shore your pleased two no Its letter perfect awl the weigh My chequer tolled me sew.
> NEW YORK, March 19 /PRNewswire/ via NewsEdge Corporation - > > The New York State Society of CPAs (NYSSCPA) has problems > with H & R Block's current advertising campaign regarding > the filing of complex tax returns. P. Gerard Sokolski, > NYSSCPA president, believes that the ads are misleading and > detrimental to consumers. > > According to Sokolski, H&R Block claims that it prepares > more complex tax returns than any CPA firm in America. When > challenged, Steven A. Christianson, H&R Block Assistant Vice > President, said that they define "complex" as individual > returns with schedules. He added that the qualification > "makes it clear that H&R Block does not purport to prepare > tax returns that are more complex than the tax returns > prepared by CPA firms." How clever of HRB. The problem is grammatical: Does the adjective "more" modify "complex" or "returns"? HRB suggests that the sentence means it files "a greater number of complex returns" than any CPA firm (i.e., it files "more...returns"). Given its definition of a "complex return," that statement may be true. However, the consumer is likely to read it as meaning that the returns HRB files are "more complex returns" than those filed by any CPA firm. That statement is clearly false. This is a wonderful (and misleading) use of a grammatical ambiguity.
Given a text consisting of words separated by BLANKS or NL (new-line) characters, convert it to a line-by-line form in accordance with the following rules: (1) line breaks must be made only where the given text has BLANK or NL (2) each line is filled as far as possible, as long as (3) no line will contain more than MAXPOS characters.
The program's input is a stream of characters whose end is signaled with a special end-of-text character, ET. There is exactly one ET character in each input stream. Characters are classified as * break characters - BL (blank) and NL (new-line); * non-break characters - all others except ET; * the end-of-text character - ET. A word is a non-empty sequence of non-break characters. A break is a sequence of one or more break characters. Thus, the input can be viewed as a sequence of words separated by breaks, with possibly leading and trailing breaks, and ending with ET. The program's output should be the same sequence of words as in the input, with the exception that an oversize word (i.e., a word containing more than MAXPOS characters, where MAXPOS is a positive integer) should cause an error exit from the program (i.e., a variable, Alarm, should have the value TRUE). Up to the point of an error, the program's output should have the following properties: 1. A new-line should start only between words and at the beginning of the output text, if any. 2. A break in the input is reduced to a single break character in the output. 3. As many words as possible should be placed on each line (i.e., between successive NL characters). 4. No line may contain more than MAXPOS characters (words and BLs).
As any experienced conversationalist can tell you, ambiguity is the key to winning any argument. Following are a few popular proverbs and counter-proverbs that will allow you to turn a conversation in any direction you want. Who can argue with the wit and wisdom of our fore fathers?