Presentation: Fallacies - Relevance - PowerPoint Presentation

Slide1

Presentation: Fallacies - Relevance

vs.

Weak InductionSlide2

Homework

Study Fallacies 1-18

Review pp. 103-132

Fallacies (definition § 4.1)

§ 4.2 Fallacies of Relevance (1 – 8)

§ 4.3 Fallacies of Weak Induction (9 – 14)

For Next Class: pp. 139-152

§ 4.4 Fallacies of Presumption & Ambiguity (15 – 22) Slide3

Fallacies of RelevanceSlide4

Relevance vs. Weak Induction

Fallacies of Relevance

Premises are logically immaterial to conclusion

Typical features:

tactic of distraction

conclusion rests on emotional appeal

Premises may appear to be psychologically relevant

Fallacies of Weak InductionPremises are relevant to conclusionInsufficient evidence to warrant conclusionSlide5

Fallacies of Relevance

Appeal to Force

Appeal to Pity

Appeal to the People

Direct

Indirect

Argument against the Person

(Ad hominem)

Abusive

Circumstantial

You, too!Missing the PointOf AccidentStraw ManRed Herring

In each case,The premises are immaterial to conclusionPremises often distract attention from relevant evidenceSlide6

Fallacies of Relevance

Appeal to the People

Two Kinds

Direct Approach

Appeal to group

Appeal to emotions, either positive or negative

Evidence overlooked due to cloud of emotional attachment

Indirect Approach Appeal to individualsAppeal to attachment or relationship to crowdEvidence overlooked in favor of emotional attachment

Political speech

AdvertisementsSlide7
Slide8

Fallacies of Relevance

Ad Hominem Arguments

(against the person)

Three varieties

Abusive

: attack on character of arguer

Turn attention away from the argument to the arguer

Circumstantial: attack by reference to specific irrelevant circumstances affecting arguerEvidence for proposed conclusions overlooked in such attacksYou, too!: attack by charge of hypocrisyIrrelevant behavior characteristics overshadow argumentSlide9
Slide10

Fallacies of Relevance

Red Herring (stinky fish)

Someone diverts attention from subject at hand

Introduction of a controversial, hot-button issue

The original argument tied illegitimately to controversial position (the stinky fish)

Controversial position attacked for its outlandishnessSlide11

Fallacies of Relevance

Example: Question of Evidence (

red herring

)?

Appearing on ABC's This Week, the Ohio Republican (Minority Leader John Boehner) was asked what to describe the GOP plan to dealing with greenhouse gas emissions, "which every major scientific organization said is contributing to climate change."

Boehner replied: "The idea that carbon dioxide is a carcinogen that is harmful to our environment is almost comical. Every time we exhale, we exhale carbon dioxide. Every cow in the world, you know when they do what they do you've got more carbon dioxide."

"It's clear we've had change in our climate," he added. "The question is how much does man have to do with it and what is the proper way to deal with this? We can't do it alone as one nation."

The Huffington Post

, “Boehmer

Cites Cow Farts to Downplay Global Warming”

Red Herring?

Oversimplification?

Weak Induction

The premises are relevant to conclusion

Premises provide insufficient evidence to warrant conclusion

Relevance

The premises are immaterial to conclusion

Premises often distract attention from relevant evidence

Two Distinct FallaciesSlide12

Fallacies of Relevance

Straw Man

Someone misrepresents another’s argument

Presents weaker argument

Straw man vs. real man

Attacks weaker argument as if it were the original

Distorted argument often a fabricationSlide13

Fallacies of Relevance

The Darwinian theory of evolution cannot be true. Evolution asserts that the human being is a descendant of certain primate species. My parents are certainly human, as were theirs. Just as it is absurd to believe that a human being could birth a chimpanzee, it is absurd to believe a monkey could produce a human.

A misrepresentation of

Dawinian

theory of evolution.

As such

irrelevant evidence

against.Slide14

Fallacies of Relevance

Question of Evidence?

" The most talked-about aspect of the defense case undoubtedly concerned Mark Fuhrman, the LAPD officer who had found the bloody glove and who, as a prosecution witness, denied using the word "nigger." It turned out that Fuhrman had used "the n word"--many times--and it was on tape. Laura Hart

McKinny

, an aspiring screenwriter from North Carolina, had hired Fuhrman to consult with her on police issues for a script she was writing.

McKinny

taped her interviews with Fuhrman, who not only used the offensive racial slur, but disclosed that he had sometimes planted evidence to help secure convictions. Needless to say, the defense wanted

McKinny on the stand, and they wanted the jury to hear selected portions of her tapes. The prosecution strenuously objected, arguing that McKinny's testimony was irrelevant absent some plausible evidence suggesting that evidence was planted in the Simpson case. The prejudicial value of the testimony, the prosecution insisted, would exceed its probative value.”

The Trial of O.J. Simpson by Doug LinderSlide15

Fallacies of Relevance

Appeal to Force

Appeal to Pity

Appeal to the People

Direct

Indirect

Argument against the Person

AbusiveCircumstantialYou, too!Missing the PointOf AccidentStraw ManRed Herring

Premises are logically immaterial to conclusion

Attention drawn away from supporting evidence

appeal to some irrelevant concernoften intentionally deceptive

Premises appear relevantSlide16

Homework

Study Fallacies 1-18

Review pp. 103-132

Fallacies (definition § 4.1)

§ 4.2 Fallacies of Relevance (1 – 8)

§ 4.3 Fallacies of Weak Induction (9 – 14)

For Next Class: pp. 139-152

§ 4.4 Fallacies of Presumption & Ambiguity (15 – 22)