Lecture 3-4 - Sharpen Edges

We're right in the middle of
reconstruction. We did stage one last

week, cuz that's just close analysis. In
the previous section we did stage two,

which is to remove excess verbiage, and to
put the explicit premises and conclusion

into standard form. And this lecture is
going to focus on stage three, which is

the clarify the premises and to break them
up. Where it's possible without distorting

them. Let's start with step four, which is
to clarify the premises and the

conclusion, when it's needed. So we might
need to clarify them just in order to make

them easier to understand, or to make them
less likely to mislead, and all that

sounds pretty good. So let's try on this
example. It was hot today, so it'll

probably be hot tomorrow again. And we
need to clarify that. What exactly counts

as today? Is that, you know, the time when
there's daylight, or does it also include

night, even though night is not day? And
what exactly do we mean by hot? How hot

was it today, and how hot will it be
tomorrow? And what, after all, is heat?

And what about, it'll probably be hot
tomorrow? Probability. That's a tough

notion. We're going to spend a whole week
on that later on in the course. And there

are different kinds of probability, and I
want to know what kind you're talking

about here. And when you ask for example,
about it will be hot tomorrow, what is,

what does will mean? It means it's going
to happen in the future, and what exactly

is the future? And is the future real? Is
time real? You can go a long way towards

asking how to clarify that argument. But
that's ridiculous, you know. We don't have

to clarify a simple argument like it was
hot today so it will probably be hot

tomorrow. And it's lucky we don't have to
clarify every word in the argument because

we couldn't because after all when you
explain one of the words or give a

definition for it, it's going to be in
terms of other words and then they have to

get clarified and you'll never going to
get to the end of it. The search for

perfect clarity and absolute precision is
impossible. You'll never complete that

search. You'll never find perfect clarity
or absolute precision, so give it up. What

we should seek is not absolute precision,
but adequate precision. Not absolute

clarity, but adequate clarity. And that
means that we ought to try to clear up

those parts of the premises and conclusion
that are likely to produce confusion

later. And you have to be able to kind of
predict whether this part of the argument

needs to be clarified, because people are
going to get confused by it. Now that's

not going to be easy, and there's no
simple or mechanical rule to tell you what

needs to be clarified, and what doesn't
need to be clarified. The only way to

learn this skill is to go through some
examples that will give you models of what

needs to be clarified and what doesn't.
Sometimes, you know, in clarity lies in a

single word. In the 1980's Nancy Reagan
used to say, just say no to drugs. What

does that mean? Well, she is telling you
not to use drugs, to say no when somebody

offers you drugs or tries to tell you to
use drugs. So, in effect, she's saying you

ought not to use drugs. That's pretty
clear but now what does she mean by drugs?

Does she mean aspirin? I don't think she's
telling you not to use aspirin. Does she

mean prescription drugs? I don't think
she's telling you not to follow the advice

of your doctor and use the prescriptions
that the doctor told you to take. So that

can't be what she means. Well, maybe she
means illegal drugs. Okay. Maybe she means

illegal drugs. What about heroin or
cocaine? Yes, that's what she is telling

you not to do. She is definitely telling
you not to take illegal drugs, but then

there are some things in the middle. She
might be telling you not to take dangerous

drugs whether they are illegal or not.
What about nicotine? What about alcohol?

Those are both dangerous drugs, at least
when you use in excess. Alcohol is very

dangerous, and smoking can lead to lung
cancer, and that's how most people get

nicotine. So maybe she's telling you not
to take nico tine or alcohol in addition

to illegal drugs heroin and cocaine. Now
it's not clear, so how do we clear it up?

Well, you want Nancy Reagan's claim to
look as good as possible. Remember, you're

always trying to make the argument look as
good as possible. And one way to make it

look good is to make her claim no more
than she has to claim. So, she could be

claiming, in addition to heroin and
cocaine, you shouldn't take alcohol and

nicotine. But probably, or at least more
plausibly, she's telling you not to take

illegal drugs. She had to chose between
interpreting her and saying don't take any

illegal drugs and don't take any dangerous
drugs. And it's seems like a more

charitable interpretation that makes her
claim look more plausible is don't take

any illegal drugs. So we could clarify her
claim, just say no to drugs, by

interpreting it to mean you ought to not
to take any illegal drugs. So in general

then, the lesson is that, when there are
options about how to clarify a certain

sentence, we ought to pick the most
charitable option that makes the claim

look as good as possible. Here's another
example, where the unclarity can be traced

to a single word, but in this case it's
the word that," and it's not clear what it

refers to. So imagine that someone argues
like this. Let's say, she claims, that our

strategy won't work, because the enemy
knows our plan, but that is a big mistake.

What does that refer to? That could refer
to, that is the word that could refer to

that the enemy knows our plan. If someone
says, that's a mistake, they might be

saying, it's a mistake to think that the
enemy knows our plan. But it could refer

to the claim that our strategy won't work.
They could be saying, it's a mistake to

think our strategy won't work. Or, they
could be saying that the mistake is to

think that the enemy knowing our plan is
enough to make it not work. He might be

saying, it's not that it won't work
because the enemy knows the plan. Or,

here's a fourth possibility. He could be
saying, that is a mistake to think that

she claims that, that's not what she
claims. So, there are four different ways

to interpret, this argument, and in order
to figure out how to interpret it, we have

to figure out which of those is most
likely as an interpretation of what the

arguer is trying to say. And that's going
to depend on which one makes the argument

look the best. Now in this example it's
not clear which interpretation is the

best, because someone might give that
argument in a context where they're saying

the mistake is to think she claims that.
But in other cases they might be saying

that the mistake is to think that the
enemy knows our plan. They don't really

know our plan, and in other cases that
might be claiming that other things are

mistaken. So, we need to figure out what
the person is saying, but that could

depend on the particular context. It might
vary from context to context. Now these

unclarities seem unintentional. But
sometimes people use unclearity to hide

problems with their argument, to try to
fool you. So imagine, a politician says we

need to stop our enemies and stand by our
friends, so we must remain strong and

resolute. Well, if somebody starts arguing
like that, you ought to be asking

yourself, who do they think our friends
are? Who do they think our enemies are?

What do they mean, stop our enemies? Are
they calling for military action? How do

they think we ought to stop our enemies?
And standing by our friends. Does that

mean we ought to support'em, no matter
what they do? There are lots of questions

that you would want to ask, to clarify
exactly which claim is being made before

you accept something like this. Here's
another claim that might be made by an

opponent of the first politician. We have
to help the needy. Well, wait a minute.

Which people are needy? I mean everybody
needs something. How needy to you have to

be needy? And we ought to help the needy.
Well how are we gonna help them? Does that

mean we just give them what ever they
want, or what are we suppose to give them?

And when are we suppose to give them an d
how much are we willing to spend on giving

it to them? Politicians on both sides of
the political spectrum make vague claims

that need to clarified before you should
be willing to endorse one or the other of

those claims. If you try to decide what to
believe before you know exactly what the

claim means, before you've calrified it,
you can end up commiting yourself to all

kinds on nonsense and all kinds of very
problematic positions. You can get

yourself in to a lot of trouble. That's
why we need to clarify the terms in

arguments. Now, one special way in which
premises need to be clarified, is that

they need to be broken up into smaller
parts, where you can do that. And the

point of this, is that the smaller parts
are going to be easier to understand, and

easier to assess for whether they're true
or not. So, step four, to clarify the

premises, belongs together with step five,
break up the premises into parts. What

needs to be broken up? Well, the explicit
premises and sometimes the conclusion as

well. Here's a simple example. That shirt
looks great on you and it's on sale, so

you ought to buy it. We might put that in
standard form like this. That shirt looks

great on you and it's on sale is the
premise and the conclusion is you ought to

buy it. But notice that the premise has
two parts, joined by an and. So we could

break them up and have the first premise,
that shirt looks great on you, and the

second premise it's on sale and then the
conclusion is you ought to buy it."

Breaking up like that is supposed to make
it easier to assess the premise for truth

or falsehood. Now in this case it doesn't
make it much easier cause it was so simple

to begin with, but we'll see that breaking
up premises will really help when we get

to more complex examples. So, it makes
sense to break up premises. Well, at least

sometimes. We should not break up premises
when breaking them up distorts the

argument. Here's an example of that. We
still need to add either one more cup

white of suger, or one more cup of brown
sugar to complete the recipe. So we've got

to add another cup of ingredients. Now one
way to represent that argument would be to

say the premise is, we still need to add
one more cup of white sugar, or one more

cup of brown sugar, and the conclusion is,
we have another cup of ingredients to add.

But we can break it up cuz it's got parts.
We can change the argument into we still

need to add one more cup of white sugar.
That's the first premise, and the second

premise is we still need to add one cup of
brown sugar. And then the conclusion is we

have one more cup of ingredients to add,
but that argument doesn't make any sense.

If we've got to add one of white and one
of brown, we don't just have one more cup

of ingredients to add. And as always we're
supposed to be making the argument look

good and that change made it look bad. And
the problem is that here we broke up the

word or. Because it's one cup of white or
one cup of brown and presumably you didn't

know which it was, or maybe you had a
choice between the two but you weren't

suppose to add both. That would be too
much, and the word or signals that. So in

general, you should not break up when the
word that joins the two is or, but it's

okay to break up when the word that joins
the two is and. You still got to be

careful about context. It's not always
goint to work that way, but as a general

rule you know, that usually works. Other
cases are even trickier. One particularly

problematic case is dependent clauses.
Here's an example. Nancy finished all her

homework because all she had to do was
write 25 lines of poetry, and she wrote

two sonnets, which have fourteen lines
each. The dependent clauses, which have

fourteen lines each. And the question is,
how do we fit that into standard form.

Well, here's one stab. The first premise
can say, all she had to do is write 25

lines of poetry. And the second premise
can be, she wrote two sonnets which have

fourteen lines each. And then the
conclusion is, Nancy finished all her

homework. Now the question is can we break
up that second premis e into two different

parts? It seems like we can. We should be
able to represent the argument. So the

first premise is, all she had to do is
write 25 lines of poetry and the second

premise says she wrote two sonnets and the
third premise is sonnets have fourteen

lines each and the conclusion is she
finished all her homework. In this case,

breaking down the premise actually helps
us understand and asses it. Because we can

decide whether it's really true, for
example, that sonnets have fourteen lines

each. That's going to be a question. If
the answer is no, then the argument might

fail. The answer is yes, at least for
standard sonnets. So the argument looks

pretty good. Contrast that example with
this one. Our legal system isn't fair

because authorities go easy on white
collar criminals who have been allowed to

get away with their crimes in recent
years. Well the premise, could be,

authorities go easy on criminals who've
been allowed to get away with their crimes

in recent years. And, the conclusion is,
our legal system isn't fair. Now the

question is, can we break up that first
premise, cuz it has the dependent clause,

who've been allowed to get away with their
crimes in recent years. Well that depends,

because the person giving the argument
might be saying that authorities go easy

on all white collar criminals. And, they
might be saying that authorities only go

easy on a certain subset of white collar
criminals, namely the subset they've been

allowed to get away with their crimes in
recent years. If the premises now all

white collar criminals, then we can break
it up so that one premises says

authorities go easy on white collar
criminals, and the next premise says white

collar criminals have been allowed to get
away with their crimes in recent years.

But if the arguer is only talking about
some white collar criminals, and admits

that other white collar criminals have not
been allowed to get away with their crime,

then he's only saying that authorities go
easy on those white collar criminals who

have been allowed to get away with their
crime, that subset of white collar

criminals. And then it would distort the
argument to break it up, because if you do

break it up then that second premise says
white collar criminals have been allowed

to get away with their crimes in recent
years. And if some of them haven't, then

that premise turns out to be false. So if
you break it up you can criticize it by

pointing out that it doesn't really apply
to all white collar criminals, but if you

leave it as a single premise then it's not
subject to that criticism, so if you want

to be charitable, you probably ought to
keep this premise together. Unless you

know, on independent grounds, that the
person was making that claim about all

white collar criminals and not just a
subset. So to make that argument look

better we don't break up the premise and
the general lesson is that with dependent

clauses like that and with and who, you
have to look very carefully to figure out

what the speaker wanted to say and what's
going to make their argument look best.

And use that information to determine
whether or not break up the premise. There

are no air tight rules as always, so we
need to do a few exercises to practice the