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C H A P T E R 2 Claims, Issues, and Arguments
very argument contains at least one intended conclusion plus one or more supporting reasons, called premises. However, in some passages it is not easy to tell whether an argument occurs at all, nor what the premises and conclusion of an argument are, nor how other arguments in the passage are related to that argument. This chapter explores that understatement. It begins with an introduction of special phrases that often indicate the presence of premises and conclusions. Then the chapter investigates the problems of identifying the unstated premises and conclusions of intended argumentation. For especially complex argumentation, the chapter introduces a diagraming technique that can display argument structure.
What is a Claim?
Claims are statements. Here is one: ―Neptune has the fastest winds in the solar system.‖ An important claim might be called a proposition , assertion, judgment , hypothesis , principle , thesis , or, in some situations, a law. Claims have to be capable of being true or false. So, if you say, ―It‘s midnight,‖ then you have made a claim, but you haven‘t if you ask, ―Is it midnight?‖ or say, ―Don‘t go out after midnight.‖
Although there‘s a difference between a declarative sentence and the claim made with that declarative sentence, this book will often not honor that distinction and will speak of declarative sentences themselves as being claims.
────CONCEPT CHECK────
Is the following sentence a claim?
The biggest question your pre-historic ancestors faced was, "Is that thing behind the bushes my next meal, or am I its next meal?"
E
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You can‘t spot the claims if you don‘t speak the language. In the passage below from a famous Valley girl, try to decide whether the phrase in italics is (used to make) a claim. You won't be able to figure this out if you don‘t speak a little Valley-girl-ese.
So, I loan Whitney my copy of GQ , right, and she drops strawberry yogurt right on the cover, and like I could totally be so edged , but I tried to be cool.
To tell whether it's expressing a claim, you don't have to be able to figure out whether it's true, but only whether it could be--whether it's the sort of thing that might be true or might be false. It does make the claim that the speaker could be upset by Whitney's dropping strawberry yogurt on her copy of GQ Magazine.
What is an Argument?
The word argument has more than one meaning. In this book we will not use the word in the sense of being unpleasantly argumentative. Instead, it will normally mean a conclusion supported by one or more reasons.
It takes only one person to have an argument, not two. Saying that two people are "in an argument" means that there are two arguments, not one, in the technical sense of ―argument.‖
(^8) Answer: The question itself is not a claim, but the larger sentence containing the question is a
claim. It is used to make a claim about the question.
For any conclusion, the premises used directly to support it are called its basic premises. In a more complicated argument, there may be reasons for the reasons, and so on. But these reasons for the reasons are not part of the core. The core of the argument is the conclusion plus its basic premises.
────CONCEPT CHECK────
Pick the one best choice for the conclusion of Sanderson's argument in the following disagreement.
Sanderson: Do you realize just what sort of news you get on a half-hour American TV news program?
Harris: Yes, newsy news. What do you mean?
Sanderson: Brief news, that's what.
Harris: Brief news like boxer shorts?
Sanderson: Ha! Look at a time breakdown of the average half-hour news program broadcast on American TV. It is nine minutes of news!
Harris: What's the rest?
Sanderson: Eleven minutes of commercials, six of sports, and four of weather. You can't do much in nine minutes. I say nine is not enough if you are going to call it the "news." What do you think?
Harris: It is enough for me. News can be boring. Besides, if the American public didn't like it, they wouldn't watch it.
Sanderson: Now that's an interesting but ridiculous comment. But I‘ve got to go now; let's talk again after lunch.
Sanderson‘s conclusion is
a. If the American public didn't like brief TV news, they wouldn't watch it.
b. Do you realize just what sort of news you get in a half-hour American TV news program?
c. That's an interesting but ridiculous comment [about the American public's taste].
d. There is not enough news on a thirty-minute TV news program in America.
e. An average half-hour American TV news program is eleven minutes of commercials, nine of news, six of sports, and four of weather.
After choosing Sanderson's conclusion from the above list, comment on the quality of his argument for that conclusion.
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What is the Issue?
We argue in order to settle issues. Issues arise when there is uncertainty about whether to accept or reject a claim. For example, someone argues for the claim that you ought to quit eating strawberry yogurt because it causes cancer, and you wonder whether it really does. You are wondering about the following issue:
whether eating strawberry yogurt will cause cancer.
It's common to express an issue by using the word "whether" to indicate the uncertainty involved. You don‘t want to express the issue by taking just one side of the issue.
When two people are "in an argument," they are divided on the issue. The metaphor is that they are on opposite sides of the fence.
10 Answer (d) is correct. Sanderson's conclusion is that more time should be spent on the news during a thirty-minute TV news program. Answer (e) is wrong because it is simply a fact that Sanderson uses in his argument. It is something he wants the reader to believe, but it is not something he is arguing for. Regarding the quality of Sanderson's argument, saying only "I don't like his argument" is insufficient; it doesn't go deep enough. This kind of answer is just opinion. To go deeper, the opinion should be backed up by reasons. The weakest part of Sanderson's argument is that he isn't giving us good enough reasons to believe his conclusion. He makes the relevant comment that news occupies only nine minutes out of thirty. He then suggests that you cannot "do much in nine minutes," and he evidently thinks this comment is a reason to believe his conclusion, but by itself it is weak. He probably believes it is obvious that nine is brief, but he ought to argue for this. It's not obvious to his opponent, Harris. Harris could respond by saying, "You can do nine minutes' worth of news in nine minutes. What do you want instead, ten minutes?" Sanderson should have mentioned that too much important news is left out in nine minutes and then tried to back up this remark.
What is the best way to rewrite the sentence in order to remove the confusion?
a. The claim of whether an oppressive government is better than no government is an issue open to refutation.
b. The issue of whether an oppressive government is better than no government is a refuted claim.
c. The claim that an oppressive government is better than no government is controversial and open to refutation.
d. The issue of whether an oppressive government is better than no government is a position open to refutation.
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Our example above used the slippery term ―refutation.‖ If you claim what somebody just said is false, then you aren't refuting their claim; you are simply disagreeing with it. In order to refute it, you'd have to make a successful case that what they said is false. You can‘t refute someone‘s claim merely by contradicting it.
────CONCEPT CHECK────
What is the issue in this argument?
You politicos keep arguing that institutions can't be changed when, in fact, they change all the time. Haven't they ever heard of the institution of slavery? It‘s gone from this continent, isn‘t it?
a. Can institutions be changed?
b. Whether institution of slavery changed.
c. That institutions can be changed.
11 The topic is oppressive governments. The issue is whether an oppressive government is better than no government. One position on that issue is the claim that an oppressive government actually is better than no government. This claim is controversial. Thus you should select c as the answer to the above question. That answer is the only one that isn't using one of the following terms incorrectly: issue, position, claim.
d. That institutions can't be changed.
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The notion of an issue is explored more deeply in a later chapter.
What is a Proof?
People often argue in order to prove something. But that word ―proof‖ is a tricky word. There are different standards of proof in different situations. What is required to prove a new theorem in mathematics to the university math professors is different from what is required to prove to your neighbor that you‘re sorry to be so late in returning his shovel. Basically, though, a proof is a convincing argument, an argument that should convince people, not simply that does convince them. You prove a statement to other persons if you give them reasons that ought to convince them.
──── CONCEPT CHECK ────
Suppose you cannot locate that favorite blue shirt you want to wear. You‘ve looked in the closet where you usually keep shirts. You remember washing it at the Laundromat in your apartment building last week. Maybe you hung it back in the closet after that, or maybe you didn‘t. You can‘t remember. You don‘t remember any other time it has been out of the apartment recently. You do remember your worst case of bad memory; last year you were sure your apartment key was on the kitchen table, but then you found it an hour later on a shelf in your refrigerator. But after thinking about this you decide that is very unlikely the shirt loss is because of memory failure. You decide to do a more careful search. You look through each item of clothing in your closet, on the closet floor, and in the drawers in your dresser where you place other clothes. You look a few more places in your apartment. Then you remember that occasionally you hang clothes in the closet on top of other clothes hanging there because you don‘t have enough coat hangers. So, you search your closet one more time looking under everything hanging there. Still no shirt. So you conclude, ―This proves the shirt was stolen.‖ You start thinking about your three friends who have been in your apartment since the last time you saw that blue shirt. David was there when you went out for party supplies two days ago and came back an hour later. The shirt would fit him.
A logical reasoner hearing this story might say, ―That‘s not really a proof,‖ and this judgment would be correct. What else would it take for you to have a proof the shirt was stolen?
12 Answer (a). A yes answer and a no answer would be giving opposite answers to this issue.
Sometimes the conclusion is stated before the premises, sometimes after the premises, and sometimes embedded in the middle of the premises. Usually sentences are included that are neither premises nor conclusions; they are there for elaboration or for some other purpose, such as to entertain, to describe, to explain, to discount a possible complaint, and so forth.
Here is an example of an argument from authority that contains both kinds of indicator phrases:
Because the encyclopedia says that the whale shark is the biggest fish in the ocean, it follows that the whale shark really is the biggest fish on Earth.
The word Because indicates a premise, and the phrase it follows that indicates the conclusion. Indicators come before what they indicate. After identifying this argument, you might go on to evaluate it as being fairly strong, but as leaving out the crucial information about whether there are freshwater fish bigger than any fish in the ocean. There aren‘t.
This table provides more examples of indicator phrases:
14 Answer (b). Some good arguments have only one premise. Here is an example: "Viruses are the simplest life forms on Earth, so that virus you are looking at with your microscope is simpler than other life forms."
Premise Indicators
since
because
for the reason that
assuming
suppose
as indicated by
is implied by
given that
in view of the fact that
for
granted that
one cannot doubt that
Conclusion Indicators
therefore
consequently
thus
this means
so
it follows that
shows that
Notice how different these two arguments are.
She‘s not here, so she‘s gone to the supermarket. She‘s not here, since she‘s gone to the supermarket.
The two arguments have different conclusions, don‘t they? One of the arguments is much stronger than the other.
────CONCEPT CHECK────
Identify the indicator phrases in the following passage:
I‘ve been in love with you ever since you began going out with my friend Charles. So you shouldn't say no one loves you now that he doesn't love you anymore.
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When you are suspicious that an argument is present in a passage, the best strategy for finding it, besides simply asking the arguer whether they are arguing, is to ask yourself which statements in the passage would be reasonably convincing premises for which other statements.
────CONCEPT CHECK────
Do these passages contain arguments? If so, locate the conclusion. Identify each indicator phrase as being either a conclusion indicator or a premise indicator.
15 So is a conclusion indicator. Since is not operating as a premise indicator.
a. Never pick up a recently killed rattlesnake, because its nerve reflexes enable it to bite for some time after death.
b. Never pick up a recently killed rattlesnake. Its nerve reflexes enable it to bite for some time after death.
c. In a country with a billion people, even if you're a one-in-a-million type guy, there are still a thousand just like you.
d. Though rare on Earth, plasmas are the most common form of matter in the universe, even more common than gases.
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Discount Indicators
It is very common for passages containing arguments also to contain claims that are neither premises nor conclusions but instead signal the presence of an acknowledgment that some point that might seem to undermine the argument is weak. Here‘s an example:
16 (a) This is an argument. The conclusion is that (you should) never pick up a recently killed rattlesnake. Because is the premise indicator. (b) This is an argument with the same conclusion as in (a). Notice that the word because appeared in (a) but not in (b). Consequently, you have to work harder to locate the argument in (b). Good writers use indicator words to show their intentions to the reader. (c) This is not an argument. If there are a billion people, then being one in a million is not very special, is it? (d) This is not an argument. This kind of plasma has nothing to do with blood plasma. Besides solids, liquids, and gases, matter also takes the form of plasmas. A plasma is super-ionized in the sense that every electron has been stripped away from the nucleus. There are no ordinary atoms in a plasma. All stars are made of plasma. So are electric sparks.
All machines have a finite working lifetime. That big tree is really just a biological machine. ───────────────────────────── That big tree will stop working someday.
Creating this clear list with the conclusion below the line is called rewriting the argument in
standard form. In place of a line, if you add the symbol ‗∴’ before the conclusion, then that is
also putting the argument into standard form or standard format.
The argument we‘ve been analyzing was originally a single sentence, but this one sentence now has been shown to be composed of four statements, one being a discount claim and the other three being an argument.
The process of transforming an argument into its standard form is like the subconscious mental process that occurs when a logical reasoner "sees the argument‖ in a passage. Normally, you would take the trouble to display the argument in standard form only when confronted with an especially complicated argument that you must figure out very carefully. Nobody is suggesting that from now on you sit down with the morning newspaper and rewrite all its arguments into standard form. However, trying your hand at rewriting a few simpler arguments will help build up your skill so you can succeed with more complicated arguments when the stakes are higher.
Here is a list of what you should pay attention to when rewriting an argument in standard form:
List the premises, followed by the conclusion Remove extraneous sentences Remove indicator phrases Replace pronouns with their antecedents if possible
Draw a line between the premises and the conclusion (or else place a ‗∴’ before the
conclusion) Add implicit premises Remove ambiguity wherever possible There is no need to number the premises because premise order should not make any difference
────CONCEPT CHECK────
Rewrite the following explicit argument in standard form. Don‘t bother with implicit or unstated assumptions about not doing things that lead to your getting bit.
Even though you might be tempted, never pick up a recently killed rattlesnake, because its nerve reflexes enable it to bite for some time after death.
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Conditionals and the Word If
The word if is not in the list of premise indicator words. You cannot rely on if to indicate a premise. In argument A below if is followed by a premise, but in argument B it is part of the conclusion.
A. If, as we know, all men are mortal and Jeremiah is a man, not a god, then he is mortal, too.
B. If a mercury thermometer is given prolonged heating, it will break. This is because prolonged heating will cause the mercury to expand a great deal. But the thermometer will break apart whenever the mercury expands this much.
Let's examine argument B more carefully. Does it assume that a mercury thermometer is actually given prolonged heating? No; doing so would break the thermometer. Notice also that the conclusion is not that the mercury thermometer will actually break, but only that it will break if heated. The conclusion is an if-then statement: if the thermometer is heated, then it will break. So, the if is not indicating a premise, nor is it indicating a conclusion; it is performing another function.
If-then statements are called conditional statements or conditionals. A statement can be a conditional even if the companion word then is not present. For example:
If the Campbell's Soup Company puts less salt in its soup, sales of Campbell's soup will increase.
Does it follow from this conditional claim that Campbell's Soup Company puts less salt in its soup? No. Is the speaker committed to the claim that sales of Campbell's soup will increase? No, the commitment is only to an increase on the condition that the company does something about the salt. That is why conditionals are called "conditionals."
17 It is important to remove the first pronoun from the premise. Here is the standard form of the explicit argument:
The nerve reflexes of a recently killed rattlesnake enable it to bite for some time after death.
You should never pick up a recently killed rattlesnake.
Is the following conditional making a true statement about the real world?
If President John F. Kennedy was born in Bangladesh, then he was born in Asia.
Yes, it is true, and it is true even though both the if-part and the then-part are false. There‘s a big lesson with that example:
Later in this book we will explore in more depth the logic of conditionals, that is, reasoning correctly about conditionals.
────CONCEPT CHECK────
Answer "yes" or "no, not always" to these conditional claims:
a. If it's an apple, then it's a fruit.
b. If it's a fruit, then it's an apple.
c. It's an apple if it's a fruit.
d. It's a fruit if it's an apple.
e. It's not a fruit if it's not an apple.
f. It's not an apple if it's not a fruit.
g. If the current president of the United States were also the leader of Pakistan, then the president would be the leader of an Asian country.
h. If the tallest building in the U.S. is only 15 feet tall, then there is no building in the U.S. taller than 30 feet.
i. If Joshua Dicker or his dad, Stuart, are invited, then Joshua Dicker's dad is invited.
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19 (a) yes (b) no (c) no (d) yes (e) no (f) yes (g) yes (h) yes (i) no. In (i), if the or were and , then the answer would be yes.
The truth of a conditional does not require the truth of its parts.
Deductively Valid and Inductively Strong
The primary goal in argumentation is for the conclusion to follow from its basic premises either with certainty or with high probability. Technically, this means the arguer desires the argument to be deductively valid or to be inductively strong.
The concept of deductive validity can be given alternative definitions to help you grasp the concept. Below are five definitions. It is common to drop the word deductive from the term deductively valid :
An argument is valid if the truth of its basic premises force the conclusion to be true.
An argument is valid if it would be inconsistent for its basic premises to be true and its conclusion to be false.
An argument is valid if its conclusion follows with certainty from its basic premises.
An argument is valid if the conclusion would be true whenever the basic premises were true.
An argument is valid if it has no counterexample, that is, a possible situation that makes the premises true and the conclusion false.
This argument is valid:
All emeralds are green. The stone placed in the safe deposit box is an emerald. So, the stone placed in the safe deposit box is green.
