Description
Your assignment is to participate in the Unit One discussion forum about any issue arising in the introduction to ethics. You could criticize an argument or a stance, provide new support for a part of an argument, explain a part of one, or ask for clarity about something (try to say why it is difficult to understand). You can start a thread or respond to a classmate. It is fine to disagree with someone, but please be respectful and explain why you disagree. In your post, whatever kind it is, you should make at least one substantive point and justify it. (Even if you are asking for an explanation, try to say what is misleading or confusing and why it is.)Please write clearly, thoughtfully and grammatically.At the end of the pdf attached there are several topics chose one of them. I need about 10 sentences paragraph. I don’t need a full essay.
Unformatted Attachment Preview
Introduction to Arguments—D. Yeakel
I.
Identifying Arguments
An argument is the presentation of (what is intended to be) evidence for some claim. The two
components are the claim argued for—call this the ‘conclusion’—and the evidence for it. When this
evidence is expressed in declarative sentences we will call those sentences ‘premises.’ Although,
arguably, there can be arguments with premises and conclusions that are not declarative sentences, we
will ignore those exceptions and define an argument this way: An argument is a collection of declarative
sentences some of which (the premises) are offered as evidence for another (the conclusion). Here’s a
simple example:
Luanda is the capital of Angola. The Largest city in Angola is the capital city. So, Luanda is the
largest city in Angola.
The conclusion of this argument is the sentence ‘Luanda is the largest city in Angola.’ The other two
sentences (the premises) combine to give evidence for that claim. Frequently, though not always, there
are linguistic indicators of either premises or conclusions. In the argument above, the word ‘so’
suggests that a conclusion follows. Other words serving the same function are ‘therefore,’ and
‘consequently.’ The words ‘since,’ ‘because,’ and ‘for’ often indicate that a premise follows, though this
indication is not infallible given the ambiguity of the words. A more reliable method (than relying on
indicator words) for identifying arguments is to answer the following questions: ‘Of what is the speaker
or author trying to convince her audience?’ and ‘What reason has she given for being convinced of
that?’
Notice that if arguments are just the presentation of evidence for a claim, then we are presented with
arguments constantly. Since it is reasonable to believe only claims for which there is good evidence, we
should endeavor to discern good arguments from bad. To this end it is often helpful, after identifying an
argument, to arrange it in a way that makes its key features clear.
Standard Form
An argument is in standard form when its premises are each listed separately above its conclusion.
Often a line or some other mark is used to identify the conclusion. For example, here is the argument
above arranged in standard form:
Luanda is the capital of Angola.
The Largest city in Angola is the capital city.
∴ Luanda is the largest city in Angola.
The triangular arrangement of dots stands for ‘therefore’ and indicates the conclusion. An argument is
not restricted to a certain number of premises; it can have any number of them provided there is at
least one. Arguments are typically taken to have a single conclusion, however many extended
arguments seem to have more than one. In an extended argument, evidence is given for at least one
premise; consequently, that premise is also the conclusion of an argument. For an example, suppose
the following argument had been given for the second premise of the above argument,
Since the largest city in a country is the most economically powerful, the seat of political power is
often established there. Once a capital (a center of political power) is established in a city, that
city attracts professionals that in turn attract more services and people. So, often the largest city
in a country is the capital city. It is likely then that the largest city in Angola is the capital city.
Here is the entire extended argument in standard form,
Luanda is the capital city of Angola
The economic power of a largest city often leads to capitals locating there.
The political power of a capital city often leads to a larger population.
∴ Often, the largest city in a country is a capital city.
∴ The Largest city in Angola is the capital city.
∴ Luanda is the largest city in Angola.
Notice that arguments for a premise have been indented so that they are not confused with premises
for a different conclusion. Notice also that some premises have been paraphrased to more readily
reveal their relationship to the conclusion. In addition to not being presented in their clearest light,
sometimes arguments are not presented in full; implicit premises must be added. These unstated (yet
still relied-upon) premises complicate the process of evaluation. Not only must arguments be identified,
often they must be reconstructed. Here’s an example,
There’s no way Fidel Castro owns any private property. He’s a Marxist and no Marxist believes in
private ownership of property.
A first attempt at standard form:
Fidel Castro is a Marxist.
No Marxist believes in private ownership of property.
∴ Fidel Castro does not own property.
The premises provide evidence that Castro does not believe in private ownership of property. In order
to reach the conclusion that he does not actually own any, one needs a premise that connects beliefs
about private property with practices regarding private property. Since the author of the argument says
‘there’s no way’ Castro possesses property, she probably intends to rely on a premise like this,
No one owns property who does not believe in private ownership of property.
The reconstructed argument in standard form includes the implicit conclusion and premise.
Fidel Castro is a Marxist.
No Marxist believes in private ownership of property.
[∴ Fidel Castro does not believe in private ownership of property.]
[No one owns property who does not believe in private ownership of property.]
∴ Fidel Castro does not own property.
The brackets indicate the premises that were implicitly relied upon in the original argument.
Faithfulness and Charity
Since reconstruction of arguments requires omission of irrelevancies, alteration of premises
(paraphrasing) and addition of assumptions (implicit premises), care must be taken not to misrepresent
the argument. There are two rules to follow when reconstructing arguments: a reconstruction should
be faithful—that is, it should be consistent with the author’s intentions—and a reconstruction should be
charitable—that is, it should be the best argument possible. The first principle requires that we not add
a premise that the author disagrees with. The charity principle obligates us to present the strongest
argument we can for the conclusion. Sometimes the rules conflict.
For example, consider the argument just given. We added the premise ‘no one owns property who does
not believe in private ownership.’ This premise is almost certainly false. We might have added instead
the somewhat more plausible premise ‘few own property who do not believe in private ownership.’ We
added the premise we did because the phrase ‘there’s no way’ in the conclusion suggested that the
argument’s author intended the stronger claim. Since the argument we constructed (with the stronger
claim) has an obviously false premise, it is not the best argument we might have presented. We
followed the principle of faithfulness over charity.
The principle you follow in cases of conflict should be determined by your reasons for reconstructing an
argument. If you are writing the life story of Bob, then faithfulness should trump charity in
reconstructing Bob’s arguments. However, if you are trying to decide whether or not to accept a
conclusion, it is wiser to consider the best argument possible rather than the exact argument that Bob
intended. Following the principle of charity requires being able to tell when one argument is superior to
another. How to do that?
II.
Evaluating Arguments
Consider the following two arguments:
Argument One
The Mackenzie River runs through the United States.
The United States is in Canada.
∴ The Mackenzie River runs through Canada.
Argument Two
The Canadian head of state is the British monarch.
∴ Guatemala and El Salvador share a border.
Argument One has two false premises, so you should not accept the conclusion on the basis of
Argument One. However, it does have a nice feature that Argument Two lacks; if its premises were to
be true then its conclusion would be true. Argument Two, despite having all true premises (the only
premise is true) does not have the right relationship between premises and conclusion. We will say that
it does not have good form. Argument One has good form, but false premises. If an argument has good
form and true premises, that is, if the premises bear the right relationship to the conclusion and the
premises are true, then one should accept the conclusion of the argument. Since there are only two
requirements for a successful argument (true premises and good form) there are only two legitimate
criticisms of an argument: you could say that it has a false premise or you could say that it has bad form.
Notice that you can criticize an argument without saying that it has a false conclusion. Both Arguments
One and Two have true conclusions despite being flawed arguments. Also notice that it is not a
legitimate criticism of an argument to say that it has a false conclusion. A false conclusion might be
evidence that something is wrong with the argument. However, to identify a false conclusion is not to
identify the flaw in an argument, so it is not a criticism. There are some devious arguments that seem to
have true premises and good form yet have a false conclusion. Bishop Berkeley, an eighteenth century
theologian and philosopher (and more) gave the following argument for the conclusion that (seemingly)
physical objects are really just ideas in our mind.
We perceive objects like tables and apples.
We perceive only images in our minds.
∴ Objects like tables and apples are only images in our minds.
The second premise is plausible when we realize that we can only see the images and perceptions that
our senses deliver to us; we cannot ‘go beyond our senses’ and see physical objects as they really are.
The argument seems to have true premises. Furthermore, if the premises are true then the conclusion
must be true. So the argument has neither of the two possible flaws. However, the conclusion seems to
be obviously false. It is tempting to give reasons that the conclusion is false. For example, you might
hide an apple and then discover it where you left it to show that the apple persisted even when you no
longer had an image of it in your mind. However, this is merely to give a different argument for the
opposite conclusion; it is not a criticism of Berkeley’s argument. To say that the conclusion of an
argument is false is not to give a criticism of the argument; it is to ignore the argument, which is what
we will do, for now, to Berkeley’s argument.
Form
Determining whether premises are true typically requires evaluating evidence for them and evaluating
evidence requires evaluating the form of an argument (since good arguments must have good form).
Hence, evaluation of the form of arguments is of foremost importance in evaluating arguments.
It is important not to confuse an argument’s having good form with its having true premises. Again
consider Arguments One and Two. Argument One has good form but false premises. So, an argument
can have good form without having true premises. (It can also have true premises without having good
form, like Argument Two.) When we say that an argument has good form we are saying something
roughly like this: If the premises were to be all true then we would have reason to believe the
conclusion. This condition can be satisfied even if the premises are not actually true.
Logicians have discerned to varieties of good form. An argument can be valid or strong. First, the
definition of a valid argument:
An argument is valid if its premises, if all of them were to be true, would guarantee the truth of
its conclusion.
Here is an example,
If Cuccinelli will succeed then Bill-H.R.3590 will not remain law.
Cuccinelli will succeed.
∴ Bill-H.R.3590 will not remain law.
One does not need to know whether the premises are true to see that if they are true, then there is no
way that the conclusion could be false. Notice that this argument might have a false conclusion despite
being valid. This is possible since there are two possible flaws an argument could have, and saying that
an argument is valid is only saying that it avoids one of those flaws (bad form). A valid argument with a
false conclusion must have a false premise.
Now consider the following argument
It has never reached 80° F in Michigan in January.
All major news outlets are predicting cold weather in Michigan this January.
∴ This January it will not reach 80° F in Michigan.
This argument is not valid since it is possible that it have true premises and a false conclusion; the
premises even if true do not guarantee a true conclusion. Nevertheless, if the premises were to be true
they would provide good evidence for the conclusion, so the argument has good form. This argument is
strong.
An argument is strong if its premises, if all of them were to be true, would make the truth of the
conclusion likely, but would not guarantee it.
The final clause rules out any overlap between valid and strong arguments. The premises of strong
arguments do not provide certainty of their conclusions as do the premises of valid arguments. That
seeming drawback is balanced by a benefit. Strong arguments are ampliative; their conclusions go
beyond the information contained in the premises. This feature will not be explored here. Suffice it to
say that arguments of both types (valid and strong) are of interest to us.
It is not immediately easy to determine which arguments are valid, and which are strong (and which are
neither). Determinations about form improve with practice. There are some well-established and
reliable ways for checking for arguments for validity but they take time and effort to learn. I do not
want to discourage you from investigation of these methods; they would not be wasted if you learned
them (take logic). However, we will be satisfied with a more naïve method. What it lacks in reliability it
recovers in ease of application. To see whether the premises, if all true would guarantee or make likely
the conclusion, imagine that the premises are all true and then try to imagine that at the same time that
the conclusion is false. If this is possible then the argument is not valid. If it is not possible then either
the argument is valid or you lack imagination.
For illustration, reconsider Argument One above. Suppose (contrary to fact) that first premise is true;
the Mackenzie River runs through the United States. Maybe you picture this:
It will be obvious that it doesn’t much matter where the Mackenzie River goes inside the U.S., nor does
it matter that the U.S. is missing two states. Now suppose that premise two is true; the United States is
in Canada. Maybe now, you picture this:
Obviously, you cannot now imagine that the river does not flow through Canada. That is, the conclusion
cannot be false if the premises were to be true. Of course, these illustrations represent only one
possible way of imagining the premises are true, whereas what is important is that there be no possible
way of imagining that the premises are true while the conclusion is false. Still, it can be seen from the
imaginative exercise that there is no possible way of putting the river inside the U.S. but outside of
Canada provided the U.S. lies within Canadian boundaries. So, Argument One is valid.
Since validity and strength are both properties of the relationship between the premises and conclusion
of arguments, they are properties (only) of the form of arguments. To say that an argument has good
form and true premises, you must say either that it is sound or cogent.
An argument is sound if it is valid and has true premises.
An argument is cogent if it is strong and has true premises.
Having only two sorts of criticisms to look for simplifies the evaluation of arguments. However, as
mentioned above, some devious arguments seem to satisfy both requirements yet still have
unbelievable conclusions. Often situations like this arise because of ambiguities in language (the
Berkeley argument is no exception).
Equivocation
When a word, phrase or sentence could have multiple meanings it is ambiguous. When an argument
relies on an ambiguity for its seemingly good form it is an equivocation. The examples below are trivial
and but many equivocal arguments can be difficult to spot.
When great golfers are trapped in a bad lie they will usually escape negative consequences of it.
Tiger Woods is a great golfer.
Tiger Woods was recently trapped in a bad lie.
∴ Tiger Woods will escape negative consequences of his lie.
He often has repeat dinner guests, so at dinner parties H.L. frequently serves his former guests.
Guests at dinner parties eat whatever their host serves.
∴ So H.L.’s guests frequently eat his former guests.
Despite appearing to be a third category of argument failure (besides false premises and bad form),
equivocation is really just a way of disguising one of the two familiar problems. Typically in an
equivocation if the premises are all true then the argument has bad form, but if the argument has good
form then one of the premises is dubious. As an illustration, consider the second of the two equivocal
arguments just given. ‘Serves’ is ambiguous. ‘A serves B’ could mean either (1) that A does something
for B or it could mean (2) that A presents B as a meal. If ‘serves’ in premise one and premise two do not
have the same meaning then the argument is neither valid nor strong, despite initial appearances. So if
the argument is successful then ‘serves’ must either have meaning (1) in both premises or meaning (2)
in both premises. However, if it has meaning (1) in both premises then the second premise is false. If it
has meaning (2) in both premises then premise one is dubious. So depending on the meaning of the
ambiguous word, the problem with the argument is just one of our familiar two problems.
More on Form and Equivocation
Now let’s look at a less trivial example of ambiguity that will serve both to illustrate equivocation and to
illustrate another method for checking an argument’s validity. Look back to the very first standard form
argument above,
Luanda is the capital of Angola.
The Largest city in Angola is the capital city.
∴ Luanda is the largest city in Angola.
Letting ‘L’ stand for Luanda, and ‘A’ for the capital city of Angola, and ‘C’ for the largest city in Angola,
we could represent the argument this way,
L=A
C=A
∴L=C
This representation of the argument reveals the structure of the argument without the distractions and
ambiguities of the English language. In a way, it reveals the form of the argument. Since validity is a
feature of the form of an argument, we would expect to be able to determine whether the argument is
valid merely by investigating this representation of it. It seems that we can. It is clear (even without
imagining anything about Luanda as we would if we followed the validity-checking method described at
the end of the Form section above) that no matter what ‘L,’ ‘A,’ and ‘C’ represent, the conclusion of the
argument must be true if the premises are. For example, if Lauren is the same person as Anne (two
names) and Charlene is the same person as Anne then Lauren and Charlene must be the same person.
So the form is valid. If the form is valid then any argument with that form must be valid too. So far, it
seems like we have a nice new method for checking for validity. There is a wrinkle.
A lion is an animal.
A cougar is an animal.
∴ A lion is a cougar.
If the Luanda argument has the form above then this argument should too, but this argument is
obviously invalid since it actually has true premises and a false conclusion. If we cannot find a way to
say why the lion argument does not have the form that we attributed to the Luanda argument then we
lose our new and reasonable method for checking arguments for validity.
The answer lies in the ambiguity of the word ‘is.’ ‘Is’ can mean ‘equals’ (is identical to) as it does in the
Luanda argument. Also, ‘is’ can mean ‘has the property of being’ as it does in the sentence ‘your shirt is
blue.’ If that sentence is true, then your shirt has the characteristic of being blue; your shirt is not the
same thing as blue (whatever that is). The premises of the Lion argument, if true, use ‘is’ in the second
or property sense. But those premises could not be represented with the equals sign as could the
premises of the Luanda argument. So the invalid lion argument does not have the same form as the
Luanda argument and consequently is not a counterexample to the validity of its form.
Exercises
Reconstruct the following arguments in standard form and evaluate them in light of the material above.
1. We have an obligation to do whatever our employer tells us to do. This is clear because
employees are the property of employers. Also, property is controlled by its owner and people
have to do something if they are controlled to do it.
2. We discover our moral obligations by looking at the animal kingdom. Whatever the animal
kingdom does is natural. So, we have a moral obligation to do what is natural. Chemotherapy is
not natural. Therefore, we have a moral obligation to avoid chemotherapy.
3. If Keynes is right then governments should spend more in a recession. But obviously,
governments should not spend more in a recession; they should spend less. So, Keynes is
wrong.
4. Shamu is a whale; so Shamu is a mammal. Since mammals bear live young, Shamu bears live
young.
5. Alberto Gonzales said that the U.S. cannot wait for another terrorist attack. If we can’t wait for
something then we eagerly anticipate it. So if Gonzales was right then the U.S. eagerly
anticipates a terrorist attack.
6. Karen would like nothing more than for her son to come home for Christmas. Karen’s son did
nothing for her for Christmas. Consequently, Karen liked what she got from her son more than
she would have liked his coming home.
Purchase answer to see full
attachment
