Southern New Hampshire University
PHL-111 Introduction to Critical Thinking
Week Three Notes
USING CRITICAL THINKING FOR THE MEDIA
Chapter 6: Recognizing, Analyzing, & Constructing Arguments
What is an issue?
An issue is an ill-defined complex of problems involving a controversy or uncertainty.
Recognizing An Argument
Distinguishing Between Argumentation and Rhetoric
Rhetoric is the defense of a particular position usually without adequate consideration of
opposing evidence in order to win people over to one’s position. Rhetoric is also known
as the art of persuasion.
Types of Arguments
Argument- Reasoning that is made up of two or more propositions, one of which is supported
by the others.
Deductive Argument- An argument that claims its conclusion necessarily follows from the
premises.
Inductive Argument- An argument that only claims that its conclusion probably follows from
the premise.
Propositions
A proposition is a statement that expresses a complete thought. A proposition can be either true
or false. If you are unsure if a statement is a proposition, try putting It is true that or It is false
that at the beginning of the statement.
Examples of Propositions:
The earth revolves around the sun.
God exists.
Chris doesn’t show me enough affection.
Cheating on exams is wrong.
Toronto is the capital of Canada.
Premises and Conclusions
The conclusion of an argument is the proposition that is supported or denied on the basis
of other propositions or reasons. The conclusion is what the argument is trying to prove.
A premise is a proposition that supports or gives reasons for accepting the conclusion.
Adequate premises are based on fact and opinion, not opinion and assumptions. The conclusion
should be supported by or follow from the premises, like in the following example:
Premise: Canada has only one capital.
Premise: Ottawa is the capital of Canada.
Conclusion: Therefore, Toronto is not the capital of Canada.
Different types of premises:
Descriptive Premises- A premise that is based on empirical facts.
Empirical Fact- A fact based on scientific observation and the evidence of our five
senses.
Prescriptive Premises- A premise in an argument containing a value statement.
Analogical Premise- A premise containing an analogy or comparison between similar
events or things.
Definitional Premise- A premise containing the definition of a key term.
Nonarguments: Explanations and Conditional Statements
An explanation is a statement about why or how something is the case. With an
explanation, we know that something has occurred. For example:
oThe cat yowled because I stepped on her tail.
oI’m upset because you promised you would meet me at the student union right
after class and you never turned up.
A conditional statement is an “if…then…” statement. For example:
oIf Francoise comes from Montreal, then she understands French.
oIf 18-year-olds are emotionally mature enough to go to war, then they should be
allowed to drink alcohol.
A conditional statement by itself is not an argument because there is no claim or
conclusion that follows.
Breaking Down and Diagramming Arguments
How To Break Down an Argument
The entire argument may appear in one sentence or in several sentences.
Put brackets around each proposition in the argument.
Identify the conclusion. Ask yourself: “What is this person trying to prove?” The
conclusion is often, though not always, preceded by a word or phrase known as a
conclusion indicator, such as:
Therefore, which shows that, thus, for these reasons, hence, consequently, so, it
follows that
Identify the premises. The premises are often, though not always, preceded by a
word or phrase known as a premise indicator, such as:
Because, may be inferred from, since, the reason is that, for, as shown by, given
that, in view of
Draw a double line under the conclusion and a single line under the premise(s).
Circle any conclusion or premise indicators.
Breaking Down an Argument Intro Propositions
Steps for diagramming an argument:
1. Bracket the propositions. In breaking down an argument, start by putting brackets
around each proposition so that you know where each begins and ends. An entire
argument can be contained in one sentence, or it can contain several sentences and
propositions.
2. Identify the conclusion. Some but not all, arguments contain terms known as conclusion
indicators that help identify which of the propositions is a conclusion. For example,
words such as therefore and thus often serve as conclusion indicators.
3. Identify the premises. The final step in breaking down an argument is to identify the
premise(s). Some arguments contain premise indicators such as because and since are
common premise indicators.
Diagramming An Argument
Diagramming an argument clarifies the relationship between the premise(s) and the
conclusion, as well as the relationship between premises, so we know to present these
particular premises together.
Arguments with one premise. Start by breaking down the argument into its propositions
and drawing two lines under the conclusion and one under the premise(s). Number each
proposition in the order in which it appears in the argument. Put a circle around each
number.
Arguments with Independent Premises. Start by breaking down the argument into its
conclusion and premises, numbering each proposition in the order it appears in the
argument.
Independent Premise- A premise that can support a conclusion on its own.
Arguments with Dependent Premises. To differentiate between whether two premises
are dependent or independent, try using one and see if the remaining premise still
supports the conclusion on its own. If it does not, then it is a dependent premise.
Dependent Premise- A premise that supports a conclusion only when it is used together
with another premise.
Arguments with a Subconclusion. Sometimes a premise acts as a conclusion for the
final conclusion.
Subconclusion- A proposition that acts as a conclusion for initial premises and as a
premise for the final conclusion.
Arguments with Unstated Conclusions. In some arguments the conclusion is unstated,
allowing readers to draw their own conclusions.
In determining what an unstated conclusion is ask yourself:
What is the speaker trying to prove or to convince us of?
Evaluating Arguments
Clarity: Is the argument clear and unambiguous?
Credibility: Are the premises supported by evidence?
Relevance: Are the premises relevant to the conclusion?
Completeness: Are there any unstated premises and conclusions?
Soundness: Are the premises true and do they support the conclusion?
Constructing an Argument
Steps for Constructing an Argument
1. State the issue. What question or issue are you going to address? Word the issue in
neutral terms.
2. Develop a list of premises. When coming up with possible premises, put your personal
opinions aside. Remain objective and open-minded. Include references when appropriate.
Premises should be mostly uncontroversial.
3. Eliminate weak or irrelevant premises. Eliminate any premises that are weak or
irrelevant to the issue. Also get rid of any redundant premises- those that say essentially
the same thing as another premise but in different words.
4. Establish a conclusion. When developing a conclusion, ask yourself “What conclusion
follow from these premises?”
5. Organize your argument. This can be done by making a list or diagram of your
premises and conclusion or can be presented in written or oral form.
6. Try out your argument on others.
