Class 12 (February 2nd)

Rational (rationalism)

• Operating based on reason, logic and thinking

• The capacity to reason (i.e., being a rational, thinking human being)

• Known through the intellect, not from experience or empirical observation

Rationale (debate)

• A set of reasons

• Basic or underlying fundamental principles

Representing Arguments Visually

More complex arguments

Why Cogency?

• Why Acceptability?

• Why not simply truth?

• Why not simply probability?

Why Acceptability?

Need for a general practical term

Why not simply truth?

Often too strong a condition (one counterexample negates; postmodern concerns about truth)

Why not simply probability?

Often too time consuming or technical to determine

Is Cogency Cogent?

Acceptable for whom?

Acceptability is relative to:

• an individual

• a group of individuals

• members of a community

• members of a culture or society

Infinite Regress?

• Is A acceptable? Yes, because of B. But is B acceptable? Yes, because of C. But is C acceptable? And so on, ad infinitum!

• On this view it would be impossible to justify the acceptability of any statement

• Wittgenstein’s solution:

 

Wittgenstein’s solution:

‘If I have exhausted the justifications I have reached bedrock, and my spade is turned. Then I am inclined to say: “This is simply what I do.”’ Wittgenstein, Philosophical Investigations, 1951

Next Step in Evaluating Arguments

Steps to evaluate the strength of an argument:

1. Determine if there is an argument

2. Put the argument in standard form

3. Assess cogency using the ARG conditions

  New:

4. Check for fallacies

What is a fallacy?

• A mistake in reasoning or arguing

• A misleading or unsound argument

• Deceptive and persuasive communication

• Intentional or unintentional endorsement of false beliefs

• Errors in reasoning

Fallacy =

Poor Reasoning

•  Flaws in an argument’s form, structure or content

We Are Fallacy Detectives

1. Describe the problem

2. Name the problem

3. Fix the problem

Origins of Fallacies in Reasoning

Includes erroneous, deceptive, and misleading reasoning

• AKA sophistry

sophistry

• Erroneous reasoning = sophistry

• Sophists were unconcerned with correct reasoning or logic

• Sold tips on how to master the art of persuasion and rhetoric

• Aristotle: On Sophistical Refutations

  • = 13 forms of flawed reasoning

Causes of Fallacious Reasoning

• Vagueness and ambiguity

• Errors in an argument

• Errors in reasoning

• False beliefs

• Rhetorical techniques / persuasion

Dowden

“a violation of the norms of good reasoning, the rules of critical discussion, dispute resolution, and adequate communication”

Why Study Fallacies?

• To spot poor reasoning

• Academic self-defense!

• To provide language to describe why premises are unacceptable, irrelevant, or insufficient ….

 

1) Begging the Question

• Involves circular reasoning

• A premise assumes the conclusion

• X is true. The evidence for this claim is … that X is true

• Example: If such actions were not illegal, then they would not be prohibited by the law.

• "Your resume looks impressive but I need another reference." "Jill can give me a good reference." "Good. But how do I know that Jill is trustworthy?"  “I can vouch for her."

2) Post-Hoc Fallacy

• = Inaccurate attribution of cause and effect

• Assumption that if event one preceded event two, then event one caused event two

• A occurs before B. Therefore, A is the cause of B

Post hoc, ergo propter hoc

 = After this, therefore because of this

• Joan is bitten by a dog while visiting her friend. Two days later she comes down with a fever. Joan concludes that the dog’s bite must be the cause of her fever.

3) Amphiboly Fallacy

Ambiguous word choice or sentence structure that leads to multiple understandings

• From amphibian – more than one meaning

  • e.g., “Duck!”

• One morning I shot an elephant in my pajamas… How he got into my pajamas I'll never know.” Groucho Marx in Animal Crackers.

amphibian

more than one meaning

4) Equivocation

Using one word in two or more senses in the same argument

• Shift in meaning from one use to another

• Example: The sign said, "fine for parking here", and since it was fine, I parked there.

• My philosophy is that philosophy is very important

 

5) Ad hominem

Arguments that attack the person making the argument rather than the argument

• Can involve prejudice and discrimination

• Sometimes the person is relevant

Ad hominem (translation)

To the man

6) Appeal to Inappropriate Authority

A premise involving support of the conclusion by a well-known person who does not have expertise in the area

• Prevalent in advertising testimonials

• Argumentum ad verecundiam 

7) Appeal to Ignorance

Appeal to a lack of evidence to conclude something is false because it has not been shown to be true

• Attempt to use inability to disprove a conclusion as proof of conclusion

• Example: No one has ever proven that UFOs don’t exist. Therefore, they exist.

• = Argumentum ad ignorantium

8) Appeal to Pity

Implies someone should accept a conclusion because something unfortunate will happen otherwise 

• Example: He is an old, dying man. It is wrong to make him stand trial for alleged offenses

• = Argumentum ad misericordiam

9) Appeal to Force

Using force or pressure to justify a conclusion

• = Argumentum ad baculum

10) Appeal to Popularity

Implies that truth or acceptability is assured from popularity

• = Argumentum ad populum 

Summary

• Flawed reasoning can fool some people sometimes

• Fallacies involve mistakes in reasoning and argumentation

• Identifying fallacies in reasoning is a step in explaining why an argument is not cogent