An expression is vague if
there is no precise boundary between the cases in which it applies and the cases in which it does not apply.
Feedback: The co... [Show More] rrect answer is B. An expression is vague exactly when it lacks a precise meaning. A vague expression, in other words, is one without a sharp boundary between cases in which it applies and cases in which it does not apply. Some standard examples of vague terms are "bald," "tall," and "heap."
Which of the following expressions is vague?
hill
The correct answer is E.
Because there is no sharp boundary between things that are hills and things that are not hills, the term "hill" is vague. To see why the term "hill" is vague, just imagine a series of lumps on the ground, the first of which is very small, and each subsequent member of which is slightly larger than the last. At the beginning of the series, the lumps are definitely not hills. At some later point in the series, however, there are lumps, which definitely are hills. Yet there is no sharp, precise boundary between the hills and the non-hills. Between the items that are definitely hills and the items that are definitely not, there are many borderline cases. For this reason, the term "hill" is vague.
The terms "33," "=," "acceleration," and "mass" are not vague. Either a given number is 33, or else it is not. A number can not be a borderline case of 33; there are not numbers, which are 33 to various degrees. Likewise for mathematical equality. Either a pair of terms are equal, or else they are not. There is no such thing as varying degrees of mathematical equality.
Acceleration and mass, likewise, are non-vague concepts. There are, of course, various amounts of mass that a body can have, and also various rates of acceleration, but these facts do not mean that the concepts of mass and acceleration are themselves vague. From the fact that there are different amounts of mass, in other words, does not mean that something can have mass to different degrees. Either a thing has mass, or it doesn't. Having mass is an all-or-nothing affair. The question of how much mass one has, in other words, is different from the question of whether one has mass at all.
An expression is ambiguous if
it has two or more distinct meanings.
Feedback: The correct answer is A. An ambiguous expression is one, which has more than one distinct meaning. If the expression has multiple meanings because a single word has multiple meanings, then the ambiguity is semantic. If the expression, however, has multiple meanings because a larger phrase or clause has multiple meanings, then the ambiguity is syntactic.
Which of the following expressions is semantically ambiguous?
bank
Feedback:
The correct answer is A.
The term "bank" is semantically ambiguous. On one hand, the term can refer to the edge of a river, stream, or body of water. On the other hand, the term can also refer to a financial institution, which stores wealth.
Which of the following sentences is syntactically ambiguous?
Close doors and open windows.
Feedback:
The correct answer is A.
The phrase "close doors and open windows" could mean two different things. On one hand, it could be a command for people to close doors, and for people to open windows. On the other hand, it could be a command for people to close two sorts of things, namely doors and open windows. Because this ambiguity is not the result of a single term, such as "door," having multiple meanings, the ambiguity is syntactic rather than semantic.
It is true that the sentence "I need to deposit some money at the bank" is ambiguous, but its ambiguity is solely due to the semantic ambiguity of the word "bank." Since its ambiguity depends on the ambiguity of a single term, the sentence "I need to deposit some money at the bank" is not syntactically ambiguous. It is only semantically ambiguous.
An ad hominem argument is one in which the premises are about
the person making a point and the conclusion tells against their making that point.
Feedback:
The correct answer is A.
An ad hominem argument is one, whose premises are about the person or persons who make a certain point, and whose conclusion tells against that point. We saw that there were three kinds of ad hominem arguments: deniers, which state that the given conclusion is false; silencers, which state that someone has no right, or no permission, to make the given conclusion; and dismissers, which state that someone does not have the evidence or justification to make the given conclusion.
Which of the following arguments is an ad hominem?
Lying Larry told me that it will rain today, therefore, it probably will not rain today.
Feedback: The correct answer is B.
Because it begins with a premise about a person, and draws a conclusion that rejects that person's testimony, the argument in (b) is an ad hominem argument.
None of the arguments in (a), (c), and (d) are ad hominems, since none of them reject the conclusion of the person they mention. Finally, (e) is not an ad hominem because it does not conclude that Sam's testimony is false from Sam's screaming. (e) does not include the word "therefore," in other words.
An appeal to authority occurs when the premises are about
the person making a point and the conclusion tells in favor of their making that point.
The correct answer is B.
An appeal to authority is an argument, which supports an argument's conclusion on the basis of something about the person making the argument. We have seen three different kinds of arguments from authority: affirmers, which state that the given conclusion is true; amplifiers, which state that someone has a special right, or special permission, to make the given conclusion; and supporters, which state that someone does has particularly good evidence or justification to make the given conclusion.
Which of the following arguments is an appeal to authority?
Honest Abe told me that it will rain today, therefore, it will probably rain today.
Feedback: The correct answer is A.
Because it begins with a premise about a person, and draws a conclusion that supports that person's point, the argument in (a) is an argument from authority.
None of the arguments in (b), (c), (d), or (e) are arguments from authority, since none of them support the point of the person they mention.
A silencer is an argument in which the premises are about the person making a point, and the conclusion is that
they are not entitled to make that point in the context in which they did, so you should not listen to them.
Feedback: The correct answer is A. Silencer arguments are arguments, which state that a certain person does not have the right, or the permission, to offer the testimony that she offers
An amplifier is an argument in which the premises are about the person making a point, and the conclusion is that
they are especially entitled to make that point in the context in which they did, so you should pay special attention to them.
Feedback:
The correct answer is D.
An amplifier argument is one, which states that someone has a special right, or special permission, to make the argument that they are making. If one points to the fact that Ulrich is the assigned umpire for a baseball game, for instance, and if one also points out that assigned umpires have a special right to offer opinions about the game, then, by concluding that Ulrich's testimony is good, one makes an amplifier argument from Ulrich's authority.
A denier is an argument in which the premises are about the person making a point, and the conclusion is that
the point they are making is false.
Feedback:
The correct answer is C.
A denier argument is one, which begins with some observation about a person, and which concludes that the person's conclusion is false. A denier argument does not conclude that the person in question is unjustified, or that the person has no right to argue for her conclusion. A denier argument merely holds that a certain conclusion is false, and it does so on the basis of something about the person who draws that conclusion.
A dismisser is an argument in which the premises are about the person making a point, and the conclusion is that
they did not have enough evidence to make that point in the context in which they did, so you should not believe them.
Feedback:
The correct answer is B.
A dismisser argument begins with an observation about a person, and concludes that such a person is unjustified or unreliable in her arguments. It does not conclude that the person's conclusion is false, exactly. Nor does it conclude that the person has no right to argue. What it states is that, although there may be some chance that the person is right, the person is nonetheless unreliable or unjustified in what she argues.
A supporter is an argument in which the premises are about the person making a point, and the conclusion is that
they have more than enough evidence to make that point in the context in which they did, so you should be very confident that they are right.
The correct answer is E.
A supporter argument begins with a statement about a person, and concludes that the person has particularly good evidence for her argument, or is particularly reliable in her arguments. Supporter arguments do not simply say that a person's conclusion is true. Nor do they say that the person in question has a special right, or a special permission to argue. Rather, a supporter argument says that someone is particularly well-justified in making her argument.
An affirmer is an argument in which the premises are about the person making a point, and the conclusion is that
the premises are about the person making a point, and the conclusion is that the point that they are making is true.
Feedback:
The correct answer is F.
An affirmer argument is an argument from authority, which begins with a claim about a person, and which states that the person's conclusion is true. Affirmer arguments do not state that the person is particularly reliable, or that the person has a special right to offer her argument. Affirmers merely state that the conclusion in question is true.
An argument begs the question when
you have no reason to believe the premises unless you already have a reason to believe the conclusion.
Feedback: The correct answer is B.
An argument begs the question when the premises cannot be justified independently of accepting the conclusion. If, in order to find an argument's premises plausible, one has to already accept the conclusion of that argument, then the argument begs the question.
To refute an argument by parallel reasoning is to
show that the form of the argument is invalid, by producing another invalid argument of the same form.
Feedback: The correct answer is D.
To refute an argument with parallel reasoning, one needs to show that the logical form of the argument is invalid, and to do so, moreover, by producing an obviously invalid argument that has the same logical form.
An argument is circular if
the conclusion is one of the premises.
Feedback: The correct answer is C.
Circular arguments include their conclusions in their premises. Because one has to accept the conclusion of a circular argument in order to accept the premises, this means that circular arguments are also question-begging arguments. The converse, however, is not true. All circular arguments are question-begging, but not all question-begging arguments are circular.
Consider the following argument: "Capital punishment is clearly wrong. Every death row inmate I've ever spoken to says so. And who would know better than a death row inmate about how wrong capital punishment is?" This argument is a(n)
appeal to authority.
Feedback: The correct answer is B.
Here, the argument assumes the truth of a conclusion on the basis of the persons who support it. In this case, the conclusion is that capital punishment is wrong, and the basis is that persons who support it are death row inmates. The argument assumes, in other words, that death row inmates are right, or that they are reliable, or that they have a special permission to weigh in on whether capital punishment works. In any case, the argument is an argument from authority, since it supports a conclusion by citing a fact about the person(s) making it.
Consider the following argument: "Every climate scientist I've talked to says that global warming is occurring. But of course they would say that! They are scientists whose work is funded by the Obama administration, and so they need to advance the leftist agenda of that administration. Naturally, therefore, we should not take their view all that seriously." This argument is a(n)
ad hominem dismisser
Feedback: The correct answer is A.
Because the argument assumes that the scientists need to advance a leftist agenda, and because the argument concludes that the scientists' views are unreliable, the argument above is an ad hominem dismisser. A dismisser argument begins with an assumption about someone, and concludes that their testimony is unreliable, unjustified, or lacks the proper amount of evidence. Since the argument's conclusion is "we should not take their view all that seriously," it is a dismisser.
If the argument were a denier ad hominem, it would state that the scientists' views are false . Yet the argument does not state this. Likewise, if the argument were a silencer, it would deny that the scientists have a right to offer their testimony. It doesn't claim this, either.
The argument is not circular, since it does not assume that we should not take the scientists' views seriously. Nor is the argument an appeal to authority, since its conclusion does not support anyone's conclusion. Finally, the argument does not require some ambiguity among the premises, so it does not commit a fallacy of ambiguity, either.
Consider the following argument: "Every single one of Fred's ex-girlfriends claims that he is a cad. And yet his current girlfriend Barbie claims that Ken is a true gentleman. Clearly, Barbie would know better than any of Ken's ex-girlfriends, since she is currently dating Ken. Therefore, we should take Barbie's word for it." This argument is a(n)
appeal to authority
Feedback: The correct answer is B.
An argument appeals to authority whenever it supports an argument on the basis of something about the person, who is making that argument. In this case, the argument supports the conclusion that Ken is not a cad, and it does so by citing something about Barbie, the person who is making that argument. (More specifically, it cites that she is dating Ken.)
Consider the following argument: "Every time I've been in car accidents, it has not been my fault. Of course, some other drivers say that too, even though they are wrong. But you can trust me on this one: after all, would a faultless driver like me lie about this? Clearly not!" This argument is a(n)
fallacy of begging the question
Feedback: The correct answer is C.
The argument concludes that the driver has never been at fault before. The premise, however, is that the driver is faultless. In order to believe that the driver is faultless, however, one must already believe that the driver has never been at fault before. The premise, in other words, is stronger than the conclusion, and one would have to believe the conclusion already to accept it. Since an argument begs the question when its premises can only be justified by accepting the conclusion, this argument begs the premises.
It's worth noting, too, that this argument is also an argument from authority. It cites something about the driver--namely, that she is faultless--and it concludes that the driver's testimony is trustworthy. However, "argument from authority" is not one of the options among (a)-(e).
To refute an argument is to show that the argument is
unsuccessful in meeting its aims
Feedback:
The correct answer is E.
To refute an argument is to show that it does not successfully accomplish its aims. This is different from showing that an argument is unsound. For sometimes, an argument can be sound even though it fails to accomplish its aims. A circular argument, for instance, is sound, because the conclusion is one of the premises. However, although circular arguments are sound, they are nonetheless unsuccessful in meeting their aims as arguments. They are fallacious. To refute an argument is to show that the argument does not accomplish its aims.
A reductio ad absurdum is an attempt to show that the argument is
unsuccessful by showing that its conclusion is obviously false
Feedback:
The correct answer is B.
To offer a reductio to an argument is to present a case, which is thoroughly obvious and uncontroversial, which shows that the argument's conclusion is false. Pointing out that things move all the time, for instance, is a sufficient reductio to Zeno's paradox about motion. [Show Less]