CHAPTER 4
When Is an Argument a Good One?
Chapter 1, Exercise 1
1. Answer in text.
2. Answer in text.
3. Answer in text.
4. Deductive.
5. Answer in text.
6. Inductive.
7. Answer in text.
8. This is meant to be an inductive argument. However, it is fallacious.
9. Answer in text.
10. Conductive.
11. Answer in text.
12. Answer in text.
Chapter 2, Exercise 2
1. This argument passes all three of the ARG conditions. Note that the conclusion asserts
very little, saying only that jealousy, anger, and inadequacy may arise in the family
situation described.
2. The argument passes on A, because clearly (non-human) animals are not human
beings and even if animals do in some sense use language, they do not speak language as
human beings do; nor do they have the same culture. These points about the nature of
animals are relevant to their moral status; the argument passes on R. However, it fails on
G, because the points are not sufficient to show that animals have no moral rights. They
might have moral rights grounded on other capacities.
3. The first premise is true by definition. The second premise can be questioned. The
third premise can also be question. So A is not satisfied. The premises are all relevant
because they all bear on the connections there might be between angels and the natural
world and thus on the sorts of reasons one might have for believing in angels. Thus R is
satisfied. The premises would be sufficient to supply adequate grounds G for the
conclusion, since they deductively entail it; however, the argument is not cogent because
(A) is not satisfied.
4. Answer in text.
5. The first three premises are clearly acceptable; the fourth premise is certainly open to
question. All premises are relevant; taken together, they would be sufficient. The
argument passes on R and G but fails on A because of the fourth premise.
6. Answer in text.
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7. Premise (1) is acceptable on common knowledge, due to "can be interpreted." (2)
follows deductively from (1) if we assume that anything someone wants to do is selfish;
thus, it is arguable that the subargument from (1) to (2) passes R and G as well, and is
cogent. But (3) is objectionable and is open to falsification by counter-example. (4) is a
sweeping premise, not defensible. Hence the argument from (3) and (4) to (5) is not
cogent.
8. Here we have two arguments, both conclusions being supported by the same premise,
which we can assume satisfies A, since the professor is talking about his own experience
with his own course. The premise is relevant - R - to the first conclusion that students at
the university in general are not working as hard this year as they did last year, but for
this conclusion it fails on G. It fails on R for the second conclusion that affluence and low
standards in the high schools produce poor work habits in students, and, therefore, for the
second conclusion, it also fails on G.
9. Answer in text.
10. Answer in text.
11. Answer in text.
12. The premise is that St. Francis could have helped poor people in his time even more
if he had given his fortune directly to them rather than giving it away and then begging
for resources. The conclusion is that the reputation of St. Francis is better than it deserve
to be. The first sentence is background information and sets the context. The premise may
be questioned factually so A is in some doubt. R is met. G is not satisfied, because we
would need a more full account of what should properly contribute the the reputation of a
saint. (Are intentions more important than consequences? What sorts of intentions and
consequences...?)
13. Standardization:
(1) Commonly used words do not catch our attention because we are so accustomed to
hearing them that we scarcely notice them.
Therefore,
(2) Effective writing uses a richly varied vocabulary.
The stated premise is acceptable and relevant. It does not by itself provide adequate
grounds. The argument passes on A and on R, provided we assume that effective writing
must catch our attention. With that assumption, it also passes on G.
14. Not an argument.
15. Answer in text.
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16. Standardization:
(l) Advertising involves the testimony of interested parties.
So,
(2) Advertising is a dubious means of education.
(3) The patient's need for information will not be met by transforming the
doctor/patient relationship into one like that between Mcdonald's and its
customers.
Therefore,
(4) Doctors should not advertise.
There is a subargument from (1) to (2). This subargument passes on A,R, G. (Compare
the discussion of testimony in Chapter 5.) (3) needs defence and is not acceptable as it
stands; indeed, this is the core of the issue, so that premise should not be undefended. To
make (3) relevant and sufficient for (4), we would need to insert the premise that
advertising would transform the doctor/patient relationship into one like that between
Mcdonald's and its customers. But the instructions say not to insert extra premises or
conclusions. As it stands, the main argument cannot be regarded as cogent.
17. Not an argument.
Exercise 2: Part A
1. Answer in text.
2. Roger does not respond fully to Jim, who actually offers two arguments. Jim offers an
argument to the effect that a mediator should be neutral; Roger ignores this argument and
states a different account of mediation, one that would not require a neutral mediator.
However, Roger gives no reasons for his own theory. Nor does he give any basis for
dissenting from Jim's view. Jim also offers the argument that the United States is not a
suitable party to mediate. Roger does respond to this argument, by stating his alternative
view of mediation, according to which it presumes the ability to wield power.
3. David does respond to Alan's argument. He does so by rejecting Alan's first premise.
David is asserting that our conviction that other people think and feel is based not on their
(bodily) behavior but on their use of language. Without the first premise, the support for
Alan's conclusion would be weak.
4. Answer in text.
5. Kaitlyn does respond to the argument, because she describes ways in which the
reduced injuries might not be due to helmet use. That is, she describes possibilities that
would mean the statistics do not support the conclusion put forward by Nicholas.
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