Chapter 2: Lecture Notes. Pinning Down Argument Structure. Chapter 2. Before we can evaluate an argument, we need to understand what just what the argument in question is. We need to know what the premises and conclusion are and how the premises are supposed to support the conclusion.
Pinning Down Argument Structure
Before we can evaluate an argument, we need to understand what just what the argument in question is. We need to know what the premises and conclusion are and how the premises are supposed to support the conclusion.
Standardizing an argument: to standardize an argument is to set out its premises and conclusion in clear statements with the premises preceding the conclusion like so:
We number the premises and conclusions so that it makes it easy to refer to them by a name: the number. So we can talk about (1) or premise (1) without having to rewrite the entire premise.
Standardizing the argument gives us a clear view of where the arguer is going and forces us to look carefully at what the arguer has said (22-3). Here is an argument in standard form.
(3) Chuck is not in Atlanta.
This simple argument is in a clear, standard form.
Arguments often proceed in stages. Sometimes a premise in one argument is a conclusion of another argument. This phenomena happens in what are called subarguments.
A subargument is a subordinate argument that is a component of a larger argument, called the whole argument. Figure 2.2 shows the logical relationship of this kind of case.
From page 25.
In figure 2.2, statement (2) represented by the circled ‘2’ is the conclusion of a subargument and may be called the subconclusion. But (2) is also a premise in the main argument.
The main argument is (2) and (3) to (4), and when we add the main argument with the subargument we get what we call the whole argument.
Subarguments are necessary and useful, because sometimes you need to justify a premises with another subargument.
In figure 2.2, (4) is also called the main conclusion.
When a premise could give rise to two different conclusion, we call a divergent structure. Some would claim that Figure 2.4 has two acceptable diagrams of a divergent structure. We will prefer the more compact structure on the left.
There is no upper limit to the number
of subargument a person could have
as part of a whole argument.
Figure 2.5 to the right shows
what we call a linear structure
of an argument where:
and (3) supports (4).
Standardizing an argument is not always a simple matter. People write and speak in a way that is more disorganized (and more interesting) than the “(1) and (2), therefore (3)” format that is best for evaluating arguments. They word statements in the form of questions and commands, repeat themselves, include background and aside remarks, tell jokes, wander off the topic, and so on. These elements of colloquial writing and speech are eliminated when we put the argument in standardized form.(29)
The point of standardized form is clarity of the reasoning involved in the argument.
10 General Strategies for Standardizing Arguments
See page 31 for fuller guidelines.
Location, Scope, and Commitment
You need to realize that the conclusion of an argument can come anywhere in the passage. From the beginning to the end to anywhere in between. And sometimes the concussion isn’t stated at all, but must be inferred by the reader. So, don’t get stuck looking at the end for conclusions anyplace other than standard form.
Rhetorical questions sometimes are disguised premises and conclusions, and the same thing goes for commands/imperatives. Our argument in standard form must always be in the form of a statement.
See page 35-6 for examples of this phenomenon.
Both conclusions and premises can vary in scope:
Universal claims like (1) and (7) are easy to show false with one example. When this happens we call it a counter example. Abe Lincoln show (1) false, and for (7), well…
When formalizing an argument we have to be especially sensitive to degrees of commitment.
This is related to scope, but it relates to how committed to a particular premise or conclusion a arguer might be.
Sometimes they may give unqualified claims like (1) and (7) from before, but other times they may not.
“From the point of view of understanding and evaluating arguments, it would be convenient if people always used words to indicate the scope of their claims and the degree of commitment with which they are advancing those claims. Unfortunately, many speeches and passages are not explicit in these ways.” (37)
Patterns of Arguments:
We have seen arguments that use linked support, figure 2.5 and 2.9. We have seen divergent argument like in figure 2.4. We also have cases of combination support like in figures 2.10 (left) and 2.11 (right) below. This occurs when premises together support a conclusion.
There are also cases of convergent support like in figure 2.12 below. We will look at these arguments more in chapter 12.
And of course there are combinations of arguments that employ all or many of the patters. See figure 2.13 on page 39 for an example.
Unstated premises and conclusions:
It is possible for an argument to be presented in a passage where a premise or a conclusion goes unstated or is missing. When diagramming an argument that has an unstated premise or conclusion you can indicate the missing piece by underlining the number of the premise or name to show that you are aware that it was unstated.
For evaluating argument we need to take care to be charitable in interpreting the argument of others. We need to be fair to the arguer.
Charity and Accuracy
These two goals can conflict. So, we need to make sure that we are charitable to the arguer, but not to the point that we get away from the original argument.
Too charitable an interpretation can lead us away from accuracy and this is what we want to try to avoid.
So we want to adhere to a principle of modest charity when we reconstruct someone else's argument all the while trying to be accurate at the same time.
Terms to review:
Charity as a principle of interpretation
Convergent support Counterexample
Degree of commitment Divergent patter of argument
Linear structure Linked support
Main conclusion Missing, or unstated premise
Qualified or tentative conclusion Rhetorical question
Scope (of a premise or conclusion) Subargument
Standardizing and argument Whole argument
Unstated, or missing conclusion