COMM 114   Week Five Lecture Notes

 

“Reasoning” in Argument

 

·        We have considered claims and evidence

·        What about reasoning?

 

What is Reasoning?

Peter Angeles in the Dictionary of Philosophy:

1.  The process of inferring conclusions from statements.

2.  The application of logic and/or abstract thought patterns in the solution of problems or the act of planning.

3.      The ability to know some things without recourse directly to sense perceptions or immediate experience.

 

What is Reasoning?

A common distinction:

·        Deductive Reasoning

·        Inductive Reasoning

 

Are there others?

·        Abductive?

·        Intuitive?

·        Holistic?

 

Deductive Reasoning

·        Deductive reasoning progresses from the general to specific claim.

·        The simplest form of deductive argument is called a syllogism. This form of argument has two premises and a conclusion.

 

Example of a simple syllogism

·        Premise 1: All left-handed people are creative and funny. (All X are Y).

·        Premise 2: Congolia is left-handed. (A is X).

·        Conclusion: Congolia is creative and funny. (A is Y).

 

Do we reason in syllogisms?

Is this a logical argument?:

·        Terrorists can fight the USA over there or here.

·        We need to fight them over there so

·        We won’t have to fight them here.

 

Is this a logical argument?

·        We must fight terrorists here or over there.

·        We do not want to fight them here, so

·        We must fight them over there.

 

What is logical?

Is this?

·        A good President keeps the USA safe from terrorist attack

·        The US hasn’t been attacked since 9-11

·        Therefore Bush is a good President

 

Is this?

·        A good President cares about the environment

·        Senator John Kerry cars about the environment

·        John Kerry will be a good President

 

Quasi-logical Argument

Is this logical?  Try this:

·        All marching bands have horns

·        Horns are found on all devils

·        Therefore, all marching bands have devils

 

Most arguments are not formal syllogisms

·        Formal logic arguments are unambiguous

·        Most arguments are informal and imperfect

 

Stephen Toulmin and Formal Logic

Toulmin—a great philosopher and argument theorist

·        Analytical reasoning is incapable of describing how practical argument functions.

·        Everyday arguments can’t be cast into syllogistic form (they would always be invalid).

·        Validity/invalidity represents a false dichotomy for evaluating practical arguments

·        Symbolic logic can’t address real world issues –symbolic logic is content neutral, context free.

·        Deduction can’t produce “new” knowledge; the truth of the premises is presumed (and cannot be established through formal logic)

 

Toulmin and Practical Arguments

 

 

Inductive Reasoning

·        Inductive reasoning progresses from specific cases to a general claim.

·        Example:

·        Five studies have been conducted at Tick Tock Tech University about the effects of cigarette smoking.

·        Six similar studies have taken place at Winehard University.

·        The studies indicate that smoking has harmful effects.

·        Therefore, smoking is bad.

 

Reasoning in Argument:
Three Major Forms

·        Reasoning from Cause

·        Reasoning from Sign

·        Reasoning from Analogy

 

adapted from materials developed by Dr. Robert Gass, California State University, Fullerton

 

Reasoning from Cause

Causal Controversies?

·        Does the availability of pornography cause an increase in sexual assaults and rapes?

·        Do spotted owls need old growth forests?

·        Is intelligence hereditary?

·        Is marijuana a “gateway” drug?

·        Does sex education increase teen promiscuity?

·        Do violent cartoon shows make children more aggressive or violent?

·        Do lower class sizes increase elementary school students’ test scores?

 

Reasoning from Cause

Causal Controversies?

·        Will repealing the Oregon Legislature’s income tax increase harm Oregon schools?

·        Why do some Muslim people hate the United States so much?

·        Who is responsible for Enron’s financial collapse?

·        Would drilling for oil in Alaska decrease our reliance on foreign oil?

·        Does “pirating” music off the Web cost major record labels money?

·        Do police use racial profiling to decide which motorists to pull over?

·        Do cell phones cause brain cancer?

·        Does the “three strikes law” deter criminals?

 

Reasoning from Cause

·        Defined: One condition or event (the “antecedent”) contributes to or brings about another condition or event (the “consequent”).  For example: “Studying hard (antecedent) leads to good grades (consequent).

·        Causal relationships are inferred, not directly observed. One can observe that B follows A, but not that B is caused by A.

·        A cause must precede its effect.  For example, does watching TV violence cause children to be violent, or are children who are predisposed toward violence drawn to watch violent TV shows?

 

Types of Causal Reasoning

·        Physical or material cause: identifying a physical or biological cause of an outcome

·        Responsibility as cause: who deserves credit or blame for an outcome?

·        Circumstantial cause: attributing causation to one’s circumstances, situation, or environment

 

Types of Causal Reasoning

·        Partial or contributory cause: not a sole cause, but one of multiple causes

·        Necessary cause: a condition that must be present in order for the effect to occur

·        Sufficient cause: a condition capable of bringing about the effect in and of itself

 

Casual Reasoning Errors

·        Confusing correlation with causation

·        “Post hoc” fallacy (post hoc ergo proptor hoc)

·        Alternative causality

·        Oversimplification or reductionism: reducing a complex problem to a single, simple cause

 

Reasoning from Sign

·        Sign reasoning assumes that one thing or event is a reliable indicator of another thing or event.

·        Signs can be status symbols, economic indicators, political actions, physiological symptoms, or other indices.

·        Effect-to-cause reasoning can also be a form of sign reasoning.  For example, a physician looks at symptoms (fever, sore throat, headache) as a basis for a diagnosis (sinus infection).

 

Reasoning from Sign

·        “Circumstantial Evidence” is a form of sign reasoning.    It is indirect evidence, a fact that can be used to infer another fact.

·        Direct evidence: A witness testifies that he saw a defendant shoot a person.  The witness would be providing direct evidence of a material fact in the case.

·        Indirect evidence (circumstantial): A witness testifies that he heard a shot and when he arrived on the scene he saw the defendant standing over the body with a smoking gun in his hand.

 

Illustrations of Sign Reasoning

·        In business: economic indicators, inflation rate, consumer confidence, housing starts, unemployment rate

·        In advertising: associating products with status, prestige, elitism

·        In medicine: symptoms, fever, dizziness, blood pressure, “where does it hurt”

·        In religion: The Madonna image on a wall, crop circles

·        In law: circumstantial evidence

·        In tabloids: if two celebrities are seen together, it is taken as a sign they are having an affair (J Lo and P Diddy, again?)

 

Sign Reasoning: Key Questions

·        How reliable or consistent is the sign?

·        Is the sign fallible or infallible?  Can it be refuted?

·        Is the sign ambiguous, vague, or imprecise (could it signify something else?)

·        Is the sign relevant to the situation(could it signify nothing?)

·        Are there a sufficient number of signs?

·        Are the signs consistent? 

·        Are there negative or contradictory signs?

 

Reasoning from Analogy

·        The word analogy is derived from the Greek word “analogia” meaning a resemblance or similarity between two things.

·        Analogies are based on a similarity, comparison, or precedent. For example, “If you have been to Tijuana, Mexico, you should have no trouble being comfortable in Madrid, Spain.  Everyone speaks Spanish in both cities” (is there a fallacy here?)

·        The inference being made is that two things which resemble each other in certain known respects will resemble each other in unknown respects.

 

Reasoning from Analogy

·        Analogies can be literal (comparison of two similar things) or figurative (comparison of two things that initially appear different).

·        Literal: prohibition didn’t work with alcohol and it won’t work with marijuana either

·        Literal: The economic policies of George W. Bush and George H. W. Bush, Sr.

·        Figurative: gangs as a “cancer” on society

·        Figurative: Road rage as a “ticking time bomb”

·        Fgurative: the stain on Monica Lewinsky’s dress was the “smoking gun” in the Clinton White House sex scandal.

 

Reasoning from Analogy: Examples

·        Plato compared the world we perceive to shadows on a cave wall.

·        “Doctors get to consult medical books before making a diagnosis, so students should get to look in their texts before answering a test question.”

·        Saddam Hussein is the Adolph Hitler of the 21st century.

·        “Employees are like nails.  You have to hit them on the head to get them to work.”

·        Staying at the Paris Hotel in Las Vegas is as good as flying across the Atlantic and visiting France. 

 

Reasoning from Analogy: Illustrations

·        In politics: comparing the Iraq situation to Vietnam

·        In advertising: referring to retirement savings as a “nest egg”

·        In science and medicine: labeling HIV-AIDS to an invading army, comparing the human heart to an electric pump, DNA molecule is like a ladder

·        In religion: religious parables, “deprogramming” cult members

·        In law: case precedent or “stare decisis”

·        In economics: viewing economic competition as the “survival of the fittest,” comparing the Bush tax cuts to the Reagan tax cuts

 

Reasoning from Analogy: Key Questions

·        Are the two things being compared similar in their essential, relevant respects?

·        Is the comparison vulnerable to a “fallacy” claim?

·        Are important dissimilarities being ignored or overlooked?

·        Have enough points of similarity been drawn?

·        Are there more dissimilarities than

·        similarities?

·        Are any points of difference nonessential to the analogy?

 

Evaluating Reasoning

·        Evaluate the premises for what is “true.”

·        Identify the basis for the premises (the grounds, the evidence, the foundation).

·        Evaluate the strength of the reasons (how accurate?  How credible?)

·        Evaluate the form(s) of reasoning.

·        Evaluate the strength of the objections.

·        Evaluate the main proposition or conclusion.