Your argument is pretty good, you've used claims for your premises. Some of them
are a bit vague. But only the fourth is so vague you should delete it or make it more
precise. All your premises support your conclusion. But the argument's not strong as
stated. You're missing some glue, something tofillthegap. you're piling up evidence,
but to what end? To your third premise, I'd just say "SO?" We really don't know what
standard you have in mind for that "should." And you never used in your argument that
you're talking about college students. Won't your argument workjust as well for high
school? Is that what you want?
We'll Look at how to fillin what you've missed in the next chapter.
Cartoon Writing Lesson A
Here is a chance to reason as in your everyday life with six scenes in cartoons.
Imagine seeing the scene depicted in the cartoon. Do you believe the claim that
accompanies the cartoon? Why? Or why not? How would you convince someone
to agree with you who hasn't witnessed the scene?
Here are the steps you can go through:
1. Write down what you see—nothing else.
(Refer to the cast of characters at the front of the book.)
We can assume that those claims are true.
2. Ask yourself whether it's possible for everything you've listed to be true,
yet the claim in question to be false.
3. If the answer is no, you've already got a valid argument for the claim
in question. Since the premises are true, it's also good.
4. If the answer is yes and such a possibility isn't all that unlikely, you
know that you can't get a good argument for the claim in question.
5. The last case is if each such possibility—where what you see is true but
the claim in question is false—is very unlikely. Then look for a claim
or claims that will rule out all or almost all such possibilities to get a valid or
strong argument. That's the glue. But don't make up a story; the claim(s)
should be common knowledge, something we all know is true.
Steps (2)-(5) are exactly what's pictured on p. 41, except that here you can add the
glue.
In summary, then, for each cartoon write the best argument you can that has as
its conclusion the claim that accompanies the cartoon. List only the premises and
conclusion. If you believe there is no good argument, explain why.
To give you a better idea of what to do, I've included on the next page an
example of what Tom did with his homework.
55
56 Cartoon Writing Lesson A
Name Tom Wyzyczy Section 4
The fellow stole the purse.
The guy is in the room and he spots a purse on the table.
He looks around pretty shiftily and thinks that he can get away with
taking the purse.
So he grabs it and goes.
This isn't a course in creative writing! How do you know he thinks that he can get
away with it? That's just making up a story. How do you know he grabbed it? you
didn't see that. And what makes you say he looks around shiftily? You need to
distinguish what you see from what you deduce, if I didn't have the cartoon in front
of me, 1 could never have imagined what you saw. You needto use the observation
that almost no time passed from the time he saw it to the time the purse was gone, and
that there was no one else around. Then you can conclude he took the purse.
Also, be sure to put in the conclusion. "So he grabs it and goes" is only a step along
the way. You need some glue to get from that to the conclusion "The fellow stole the
purse," something like, "Almost anytime a guy looks around quickly and takes a purse,
he's stealing it." But that's false: Maybe he just recognized that it belonged to his
girlfriend or his mother, and when he didn't see her he decided to take it to her. It
looks like there is no good argument you can make for the conclusion.
This was your first try, and I'm sure that next time you'll know better. Describe
what you saw, and try to get from that to the conclusion.
Cartoon Writing Lesson A 57
Spot chased a cat.
2.
Professor Zzzyzzx is cold.
Dick didn't wash his hands properly.
Dick broke his leg skiing.
58 Cartoon Writing Lesson A
5.
Flo isn't really sick.
Dick should not drink the coffee.
Repairing
Arguments
A. We Need to Repair Arguments 59
B. The Principle of Rational Discussion 60
C. The Guide to Repairing Arguments 61
D. Relevance 68
• Exercises for Sections A-D 69
E. Inferring and Implying 74
• Exercises for Section E 75
Summary 76
A. We Need to Repair Arguments
Lee: Tom wants to get a dog.
Maria: What kind?
Lee: A dachshund. And that's really stupid, since he wants one that
will catch a Frisbee.
Lee has made an argument, if we interpret what he said as: Tom wants a dog
that will catch a Frisbee, so Tom shouldn't get a dachshund. After the last chapter,
you're probably thinking this is a bad argument. There's no glue, no claim that gets
us from the premise to the conclusion. We just ask "So?". But Maria knows very
well, as do we, that a dachshund would be a lousy choice for someone who wants
their dog to catch a Frisbee. Dachshunds are too low to the ground, they can't run
fast, they can't jump, and the Frisbee is bigger than they are, so they couldn't bring it
back. Any dog like that is a bad choice for a Frisbee partner. Lee just left out these
obvious claims, but why should he bother to say them?
Folks normally leave out so much that if we look only at what's said, we'll be
missing too much in trying to determine what we should believe. We can and must
rewrite many arguments by adding an unstated premise or an unstated conclusion.
When are we justified in adding an unstated premise? How do we know
whether we've rewritten an argument well or just added our own prejudices? And
how can we recognize when an argument is beyond repair?
59
60 CHAPTER 4 Repairing Arguments
B. The Principle of Rational Discussion
What assumptions are we entitled to make about anyone with whom we wish to
reason?
The Principle of Rational Discussion We assume that the other
person who is discussing with us or whose arguments we are reading:
1. Knows about the subject under discussion.
2. Is able and willing to reason well.
3. Is not lying.
What justification do we have for invoking this principle? After all, not
everyone fits these conditions all the time.
Consider condition (1). Dr. E leaves his car at the repair shop because it's
running badly, and he returns later in the afternoon. The mechanic tells him that he
needs a new fuel injector. Dr. E asks, "Are you sure I need a new one?" That
sounds like an invitation for the mechanic to give an argument. But she shouldn't.
Dr. E doesn't have the slightest idea how his engine runs, and the mechanic might as
well be speaking Greek. She should try to educate Dr. E, or she'll have to ask Dr. E
to accept her claim on trust.
Consider condition (2). Sometimes people inten
d not to reason well. Like the
demagogic politician or talk-show host, they want to convince you by nonrational
means and will not accept your arguments, no matter how good they may be.
There's no point in deliberating with such a person.
Or you may encounter a person who is temporarily unable or unwilling to
reason well, a person who is upset or in love. Again, it makes no sense at such a
time to try to reason with that person. Calm him or her, address his or her emotions,
and leave discussion for another time.
Then again, you might find yourself with someone who wants to reason well
but just can't seem to follow an argument. Why try to reason? Give them a copy of
this book.
What about condition (3)? If you find that the other person is lying—not just a
little white lie, but continuously lying—there's no point in reasoning with him or her,
unless perhaps to catch that person telling lies.
The Principle of Rational Discussion does not instruct us to give other people
the benefit of the doubt. It summarizes the necessary conditions for us to be
reasoning with someone. Compare it to playing chess with someone: What's the
point if your opponent doesn't understand or won't play by the rules?
Still, you say, most people don't follow the Principle of Rational Discussion.
They don't care if your argument is good. Why should you follow these rules and
assume them of others? If you don't:
SECTION C The Guide to Repairing Arguments 61
• You are denying the essentials of democracy.
• You are not going to know what to believe yourself.
• You are not as likely to convince others.
A representative democracy is built on the idea that the populace as a whole
can choose good men and good women to write laws by which they can agree to live.
If any appeal to the worst in people succeeds, then a democracy will degenerate into
the rule of the mob, as it did in ancient Athens. It is only by constantly striving to
base our political discussions on good arguments that we have any hope of living in a
just and efficient society.
And how can you know what to believe yourself if you've adopted methods of
convincing that appeal to the worst in people? Abandoning the standards of good
reasoning, you'll soon be basing your own life on illusions and false beliefs.
But most of all, you're wrong if you think that in the long run convincing with
clever ads, sound bites, or appeals to prejudice work better than good arguments.
They don't. I've seen the contrary in my city council meetings. I've seen it with my
friends. I've seen it with my students. With a little education, most people, most of
the time, prefer to have a sensible, good argument to think about.
If you once forfeit the confidence of your fellow citizens, you can never
regain their respect and esteem. It is true that you may fool all the people
some of the time; you can even fool some of the people all the time; but
you cannot fool all of the people all the time.
Abraham Lincoln
Still, there are times when an argument appears good, but you think the
conclusion is false. Then if you are a good reasoner, you should try to show the
argument isn't good: The conclusion doesn't really follow from the premises, or one
of the premises is false, or it begs the question.
What if you hear arguments for both sides, and you can't find a flaw in either?
Then you should suspend judgment on whether the claim is true until you can
investigate more.
The mark of irrationality If you recognize that an argument is good,
then it is irrational not to accept the conclusion.
C. The Guide to Repairing Arguments
With the Principle of Rational Discussion, we can formulate a guide to help us
evaluate and interpret arguments. Since the person is supposed to be able to reason
well, we can add a premise to his or her argument only if it makes the argument
62 CHAPTER 4 Repairing Arguments
stronger or valid and doesn't beg the question. Since the person isn't lying and
knows the subject under discussion, any premise we add should be plausible, and
plausible to that person. We can also delete a premise if it doesn't make the
argument worse.
The Guide to Repairing Arguments Given an (implicit) argument that
is apparently defective, we are justified in adding a premise or conclusion
if it satisfies all three of the following:
1. The argument becomes stronger or valid.
2. The premise is plausible and would seem plausible to the other person.
3. The premise is more plausible than the conclusion.
If the argument is then valid or strong, we may delete a premise if doing so
doesn't make the argument worse.
For example, suppose we hear:
Lee: I was wondering what kind of pet Dick has. It must be a dog.
Maria: How do you know?
Lee: Because I heard it barking last night.
Maria shouldn't dismiss Lee's reasoning just because the link from premises to
conclusion is missing. She should ask what claim(s) are needed to make it strong,
since by the Principle of Rational Discussion we assume Lee intends to and is able to
reason well. The obvious premise to add is "All pets that bark are dogs." But Maria
knows that's false (seals, foxes, parrots) and can assume that Lee does, too, since
he's supposed to know about the subject. So she tries "Almost all pets that bark are
dogs." That's plausible, and with it the argument is strong and good.
We first try to make the argument valid or strong, because we don't need to
know what the speaker was thinking in order to do that. Then we can ask whether
that claim is plausible and whether it would be plausible to the other person.
By first trying to make the argument valid or strong, we can show the other person
what he or she needs to assume to make the argument good.
It's the same when you make your own arguments. You have premises and a
conclusion, and you ask yourself: Is it possible for the premises to be true and the
conclusion false? When you find a possible way for the premises to be true and the
conclusion false, you try to eliminate it by adding a premise—of course a plausible
one. As you eliminate ways in which the premises could be true and the conclusion
false, you make the argument better.
But why go to all this bother when we hear a defective argument and can see
how to make a better one for the same conclusion? Why not just use what we can
SECTION C The Guide to Repairing Arguments 63
from it and ignore the rest in order to come up with a good argument? After all,
we're trying to learn what's true about the world. Fine, but first you should take
seriously what the other person said. You can't learn if you don't listen. The Guide
to Repairing Arguments is a method to hear and understand better by paying
attention to what's actually said.
One aid we have in following what someone actually said is to note certain
words such as "so" or "therefore," which tell us a conclusion is coming up, and
"since" or "because," which introduce premises.
Indicator word An indicator word is a word or phrase added to a claim to
tell us the role of the claim in an argument
or what the speaker thinks of the
claim or argument.
Indicator words are flags put on claims— they are not part of a claim.
Here are some common ones:
conclusion indicators premise indicators
so since
therefore because
hence for
thus in as much as
consequently given that
we can then derive suppose that
it follows that it follows from
These are good to use in our own arguments to structure our writing and help others
understand us. But most arguments we encounter won't have such clear signposts.
Other indicator words tell us what a speaker thinks of a claim or argument, as
we saw in Chapter 3 (p. 48).
E x a m p l e s Are the following good arguments? Can they be repaired?
Example I No dog meows. So Spot does not meow.
Analysis "Spot is a dog" is the only premise that will make this a valid or strong
argument. So we add that. Then since that's true, the argument is good.
We don't add "Spot barks." That's true, too, and certain to seem obvious to the
person who stated the argument, but it doesn't make the argument any better. So
adding it violates requirement (1) of the Guide. We repair only as needed.
Example 2 All professors teach. So Ms. Han is a professor.
Analysis The obvious claim to add is "Ms. Han teaches." But then the argument is
64 CHAPTER 4 Repairing Arguments
still weak: Ms. Han could be an instructor, or a part-time lecturer, or a graduate
student. The argument can't be repaired because the obvious premise to add makes
it weak.
Example 3 Dr. E has a dog named "Anubis." So Anubis barks.
Analysis We can't make this valid by adding "All dogs bark," because that's false.
We could make it stronger by adding "Anubis is not a basenji" and "Anubis
didn't have her vocal cords cut." Those would rule out a lot of possibilities where
Anubis is a dog but doesn't bark. And why not add "Anubis scares away the electric
meter reader every month"? Or we could add . . . . But this isn't a course in
creative writing. We can't make up just anything to add to the argument to make it
stronger or valid. We have no reason to believe those claims are true.
The only premise we can add here is a blanket one that rules out lots of
Richard L Epstein Page 9