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12.1: Techniques of Defining- “Semantics” vs “Syntax” and Avoiding more Ambiguity

  • Page ID
    45510
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    There are two big ways that statements can be ambiguous: they can use improper semantics or improper syntax. A semantic problem is one where you are running afoul of the meanings and word choices you have made or are using, and a syntactic problem is one where you are not phrasing or organizing your thoughts in a clear fashion. The goal with any writing is to make sure that your intended message is properly received. The best way to do this is to speak clearly, succinctly, and directly using the most precise words and grammar that you can.

    You can run into semantic problems when you

    • Don’t use the correct words to express what you intend to communicate; or
    • Use words with more than one meaning

    English has many, many words that mean the same thing, and it is always fun to use the words that are the most poetic, but you should never sacrifice clarity for the sake of prose (when writing an argumentative paper). If you’re writing poetry or fiction or almost anything except a critical paper, go ahead and go nuts with beautiful language and let the words flow from your fingertips and caress your pages like a fresh dewdrop falling on young grass at the dawn of a crisp spring morning. Otherwise, stick to the basics.

    I think it’s easiest to understand how to avoid semantic issues with examples. Look at the following sentences below and see how some sentences do a better job of communicating:

    - Dallas cop fatally shoots neighbor in apartment after mistaking it for own

    (It’s unclear what the pronouns refer to)

    - Dallas cop fatally shoots neighbor in his apartment after mistaking it for her own, police say

    (This is better, but still not clear enough)

    - A Dallas police officer fatally shot a man after she entered the wrong residence in her apartment building, thinking she was in her own home, authorities say.

    (Longer, but quite clear)

    “Fun to speak Yoda-like in riddles, is it not? Speak in whatever order you can! Versatile language is English, understand me you must.” While you still understand what I’m saying, it’s much easier if I just say, “It can be fun to speak like Yoda, and you’ll still understand me because that’s how English works.” This is just one example of how syntax can impact the ways in which people understand you, and all this does is make people have to think a little harder about what you’re saying in order to understand what you mean. There are more complex ways that syntax can go wrong and your meaning can actually be lost. The goal is to avoid any possible misperceptions in your language and meaning by doing the following

    • Use a grammatical structure that allows for no confusion.
    • Order your sentences so that they flow properly from one to another in the most natural fashion.
    • Avoid using overly long or complex language and sentences.
    • Write the most important points first and supporting ones later so that your reader has no problems following what you’re saying. When making an argument, it’s no problem to start by “spoiling” your conclusion.

    Just like with semantic problems, I think it’s easiest to understand how to avoid syntactic issues with examples. Look at the following sentences below and see how some do better jobs of communicating:

    - Georgia mother charged in murders of 4 young children, their father smiles in court

    (Who is doing the smiling? I think a comma was left out!)

    - “Do you mind if I keep going?” Answer 1: Yes. Answer 2: No.

    (The problem here is that with how the question is phrased, answering yes or no might mean the same thing – “yes, keep going” or “no, I don’t mind”

    One thing that helps to make things very clear is by examining and stating the relationship between concepts. Two very common relationships worth covering are necessity and sufficiency.

    Necessary and Sufficient Conditions23

    In a conditional statement (“If…then…”), two conditions are given: a necessary and a sufficient condition.

    Sufficient Conditions:

    A is a sufficient condition for B whenever A is all that is needed to make B true, or whenever the occurrence of A is all that is needed for the occurrence of B.

    If Fido is a dog, then Fido is a mammal.

    “Fido is a dog” is all that’s needed to make it true that “Fido is a mammal.” So “Fido is a dog” is a sufficient condition for “Fido is a mammal.” Similarly, “Fluffy is a cat,” “Pokey is a rhinoceros,” “Trunky is an elephant,” and “Ollie is an ocelot” would be sufficient conditions to make each one of them mammals.

    If it rains, the sidewalk will be wet.

    If a dog pees on it, the sidewalk will be wet.

    If someone spills soda on it, the sidewalk will be wet.

    If someone sprays a hose on it, the sidewalk will be wet.

    In each case, the antecedent (first term, after the “if”) expresses a sufficient condition for “the sidewalk will be wet.”

    Necessary conditions: B is a necessary condition for A whenever A cannot occur without B also occurring, or whenever A cannot be true without B also being true. So, in all the cases above, the consequent (second term, after the “then”) is a necessary condition.

    If Fido is a dog, then he is necessarily a mammal.

    If I spray a hose on it, the sidewalk will necessarily get wet.

    If John is older than Kevin, and Kevin is older then Lanai, then John is necessarily older than Lanai.

    In each case, the word “necessarily” is not needed, because the conditional sentence already asserts the necessity.

    For the following, fill in the blanks with “necessary” or “sufficient.”

    1. Being a quarterback in the NFL is a ___________ condition for being a football player.

    2. Being a football player is a ___________ condition for being an NFL quarterback.

    3. Being able to fly a plane is a ___________ condition for being an airplane pilot.

    4. Spraying a hose on a dog is a __________ condition for making the dog's fur wet.

    5. Being a guitarist is a _________ condition for being a musician.

    6. Being a musician is a ___________ condition for being a guitarist.

    7. Firing an unsilenced gun is a ____________ condition for making a loud noise.

    8. Being famous is a ____________ condition for being a movie star.

    9. Being a movie star is a __________ condition for being famous.

    Now, rewrite each of the above as a conditional sentence.

    Because necessary conditions are distinct from sufficient conditions, the antecedent and consequent of a conditional statement cannot be reversed if you wish to maintain the truth and meaning of the sentence. In other words, saying:

    Whenever a patient is feeling pain, the pre-occipital lobe of the brain is active.

    is not the same as saying:

    Whenever the pre-occipital lobe of the brain is active, the patient is feeling pain.

    These cases should make that clear:

    If that’s a dog, then it’s a mammal.

    If that’s a mammal, then it’s a dog.

    If you have five dollars, you have some money.

    If you have some money, you have five dollars.

    If you go outside in winter then you’ll feel cold.

    If you feel cold, then you’ve gone outside in the winter.

    If you find a sentence where the meaning stays (essentially) the same when you’ve reversed antecedent and consequent, then you’ve found a case of what we call a biconditional. The biconditional is usually written as “if, and only if…” and both conditions are necessary and sufficient for each other. For example,

    The existence of a child is a necessary and sufficient condition to know there is a parent.

    There is a child if and only if there is a parent.

    There is a parent if and only if there is a child.


    This page titled 12.1: Techniques of Defining- “Semantics” vs “Syntax” and Avoiding more Ambiguity is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Noah Levin (NGE Far Press) .