Example 8 - Summary
Here’s what we learned in
this example:
Diagramming Example 8
The argument is diagrammed
like this:
8)
“Ann should major in business. For one thing, capitalism has triumphed over
communism and so it must be the will of God. Clearly, though, business majors
foster capitalism, which shows that business majors foster the will of God. For
another thing, if Ann gets her MBA, she’s sure to be happy. After all, MBA’s
make a lot of money and people who make a lot of money are sure to be happy.”
1. Ann should major in
business.
2. Capitalism has triumphed
over communism.
3. Capitalism is the will of
God.
4. Business majors foster
capitalism.
5. Business majors foster
the will of God.
6. If Ann gets her MBA, she’s
sure to be happy.
7. MBA’s make a lot of
money.
8. People who make a lot of
money are sure to be happy.
2
A
3 + 4 7 + 8
B D
5 6
C E
1
Notice that:
·
This argument has two
lines of reasoning. The “will of God” line of reasoning (ideas 2, 3, 4, and 5)
is on the left and the “being happy” line of reasoning (ideas 6, 7, and 8) is
on the right.
·
The conclusion
indicator expression “and so” tells us that idea 2 is being given as a reason
to believe idea 3. (Were you troubled by the “and” in the “and so?” “And so,”
isn’t the same as “and.” It’s the same as “so.”) It corresponds to inference A.
·
“Clearly, though” is
sort of like an “and.” It’s an inference eraser that tells us that there
probably isn’t an inference between 3 and 4.
·
The conclusion
indicator expression “which shows that” tells us that 5 follows from something
that came before. It corresponds to inference B.
·
The reason indicator
expression “after all” tells us that 7 is a reason to believe 6. It corresponds
to inference D.
·
The inference eraser
expression “and” tells us that there probably isn’t an inference between 7 and
8.
·
There aren’t any words
in the passage that correspond to inferences C and E. (Remember, sometimes
inferences will be signaled with conclusion indicator expressions and reason
indicator expressions, but sometimes they won’t be.)
·
The premises (ideas 2,
4, 7 and 8) have arrows going from them but no arrows going to them
·
The ultimate conclusion
(idea 1) has arrows going to it but no arrow going from it.
·
The subconclusions
(ideas 3, 5 and 6) have arrows going to them and from them.
Evaluating Arguments with More than One Line of Reasoning
An
argument is good if it has even one good line of reasoning. In order to
discount an argument with more than one line of reasoning, we need to find
something wrong with each of those lines.
Evaluating Example 7
I think that this argument
is bad because I think that inference A is weak and premise 8 is false.
8)
“Ann should major in business. For one thing, capitalism has triumphed over
communism and so it must be the will of God. Clearly, though, business majors
foster capitalism, which shows that business majors foster the will of God. For
another thing, if Ann gets her MBA, she’s sure to be happy. After all, MBA’s make
a lot of money and people who make a lot of money are sure to be happy.”
1. Ann should major in
business.
2. Capitalism has triumphed
over communism.
3. Capitalism is the will of
God.
4. Business majors foster
capitalism.
5. Business majors foster
the will of God.
6. If Ann gets her MBA,
she’s sure to be happy.
7. MBA’s make a lot of
money.
8. People who make a lot of
money are sure to be happy.
2
A L
3 + 4 7 + 8
L
B D L
5 6
C E
1
Let’s summarize what we’ve learned so far.