Chapter 3- Fallacies Flashcards
Fallacy
A certain kind of defect in an argument (not by having false premises).
Fallacious Argument
An argument whose conclusion could be false even if all of its premises were true.
What are the two types of fallacies?
1) Formal Fallacy
2) Informal Fallacy
Formal Fallacy
A fallacy identified through mere inspection of the form or structure of an argument.
What is an example of a formal fallacy?
Denying the antecedent or affirming the consequent.
Informal Fallacy
A fallacy that can only be detected through analysis of the content of the argument.
What is an example of an informal fallacy?
1) Nothing is better than God.
2) A peanut butter and jelly sandwich is better than nothing.
3) Therefore, A peanut butter and jelly sandwich is better than God.
What is the “effect” of an informal fallacy?
The effect of this fallacy is to make a bad argument appear good. Sometimes the motive is to deceive- that’s called a “sophistry”.
What are the five groups that we classify informal fallacies into?
1) Fallacies of Relevance
2) Weak Induction
3) Presumption
4) Ambiguity
5) Part/Whole
What are the fallacies of relevance?
1) Appeal to Force (Argumentum ad Baculum)
2) Appeal to Pity (Argumentum ad Misericordiam)
3) Appeal to the People (Argumentum ad Populum)
4) Argument against the Person (Argumentum ad Hominem)
5) Accident
6) Straw Man
7) Missing the Point (Ignoratio Elenchi)
8) Red Herring
What is a Fallacy of Relevance?
This is a fallacy where the premises are logically irrelevant to the conclusion.
Appeal to Force (Argumentum ad Baculum)
A threat of force (or harm) is used to cause acceptance of a conclusion.
Example: A lobbyist threatens a congressman’s re-election campaign unless the congressman agrees with what the lobbyist wants.
Appeal to Pity (Argumentum ad Misericordiam)
Pity is used to get a conclusion accepted.
Example: “Oh, officer, I have already had such a bad day- my husband left me, my dog was run over by the ice cream truck- it would be the end of me, if you tell me that I was speeding.”
Appeal to the People (Argumentum ad Populum)
An attempt to win popular assent to a conclusion by arousing the emotions and enthusiasms of people rather than by appeal to the relevant facts.
Example: Marc Antony’s speech in Shakespeare’s Julius Caesar.
What are the two forms that Argumentum ad Populum can take?
Direct or Indirect
What is the effect of a Direct Appeal to the People?
Creates a mob mentality.
What is the effect of an Indirect Appeal to the People?
1) Bandwagon Effect
2) Appeal to Vanity
3) Appeal to Snobbery
Argument Against the Person (Argumentum ad Hominem)
Attacks the person, not the argument. Involves two arguers.
What are the three forms that Argument Against the Person can take?
1) Abusive
2) Circumstantial
3) “You, Too” (Tu Quoque)
Abusive Argumentum ad Hominem
Attacks or abuses the person holding the opposing position.
Circumstantial Argumentum ad Hominem
Relationship between a person’s beliefs and his or her circumstances (e.g., so-and-so is a Republican so it’s no wonder he believes X)
Tu Quoque Argumentum ad Hominem
Saying that the other person is just as bad (e.g., driving).
Accident
Applying a general rule to a particular case whose “accidental” circumstances render the rule inapplicable.
Example: Free speech is protected in this country, therefore it is perfectly legal to yell “Fire!” in a crowded movie theatre.
Straw Man
When a person exaggerates or misrepresents the opponent’s argument in order to defeat it. Involves to arguers.
Examples: Numerous in philosophy essays or when the NRA claims that the arguments of those who advocate gun-control laws really intend confiscation of all guns.
Missing the Point (Ignoratio Elenchi)
An argument purporting to establish a particular conclusion is instead directed to proving a different conclusion.
Example: A prosecutor expounding on the fact that murder is a terrible crime, then concluding that the defendant is guilty.
Red Herring
When the arguer diverts the attention of the reader/listener by changing the subject to some totally different issue- then draws a conclusion about this different issue and so claims to have won the argument.
Example: Students are always complaining about the food in the cafeteria. But eating well is important for academic success- study after study has shown that student’s who don’t eat well perform poorly in their classes.
Fallacies of Weak Induction
These arguments are fallacies because the connection between premises and conclusion is not strong enough to support the conclusion. There is at least a shred of evidence that is relevant, but isn’t strong enough to persuade a reasonable person.
What are the types of Fallacies of Weak Induction?
1) Appeal to Unqualified Authority (Argumentum ad Verecundiam)
2) Appeal to Ignorance (Argumentum ad Ignorantiam)
3) Hasty Generalization
4) False Cause
5) Slippery Slope
6) Weak Analogy
Appeal to Unqualified Authority (Argumentum ad Verecundiam)
An authority is appealed to for testimony outside the province of the authority’s special field.
Example: My brother Dan, the philosophy professor, says the roller coaster at the park is safe. So it must be safe.
Appeal to Ignorance (Argumentum ad Ignorantiam)
Argues that a proposition is true simply because it has not been proven false, or false because it has not been proved true.
Example: No one has ever seen an alien from another world, so there cannot be any life in our galaxy.
Appeal to Ignorance (Argumentum ad Ignorantiam)
Argues that a proposition is true simply because it has not been proven false, or false because it has not been proved true.
Example: No one has ever seen an alien from another world, so there cannot be any life in our galaxy.
What are the exceptions to Argumentum ad Ignorantiam?
1) Where qualified researchers have not found any evidence of a thing and they would have if it existed, and
2) In a court of law where a person is innocent until proven guilty.
Hasty Generalization
Considering only unusual or atypical cases and generalizing a rule that fits them alone- from particular to general.
Example: I have met three students from SNC, and they all had blue eyes. All the students at that college must have blue eyes.
False Cause
The link between premises and conclusion depends on some imagined causal connection that probably doesn’t exist.
Example: The last two times there was a Killeen lecture it snowed heavily. We’ll have to cancel that lecture series if we ever want nicer weather.
What are the two types of false cause inductions?
1) Non Causa Pro Causa
2) Post Hoc Ergo Propter Hoc
Non Causa Pro Causa
More general- to mistake what is not the cause of a given effect for its real cause.
Post Hoc Ergo Propter Hoc
An inference that one event is the cause of another from the mere fact that the first occurs earlier than the second.
Slippery Slope
A variety of the false cause fallacy; when the conclusion rests on the claim that a certain event will cause a chain reaction leading in the end to some undesirable consequence, yet there is not sufficient reason to think the chain reaction will occur.
Example: The faculty are asking for a coffee machine in the lounge, but if we put in a coffee machine, they’ll next want a microwave oven, then a full-sized range with a convection oven… there’s no room for all these kitchen appliances in the lounge, so we’ll have to turn down this request.
Week Analogy
An inductive argument from analogy where the analogy isn’t strong enough to support the conclusion.
Example: Ronaldo is tall, brown-eyes, dark-haired and a fantastic soccer player. Bill is tall, brown-eyes, and dark-haired… so he must be a great soccer player too.
Basic structure of an analogical argument:
- Entity A has attributes a, b, c, and z
- Entity B has attributes a, b, and c
- Therefore, entity B has attribute z.
Fallacies of Presumption
Arise because the premises presume what they purport to prove.
Fallacies of Ambiguity
Arise from the occurrence of some form of ambiguity in either the premises or the conclusion (or both). “Ambiguous” means susceptible to different interpretation in a given context.
Part/Whole Fallacies
Where a property of a whole group (or class) is improperly distributed as properties of the individual members of the group (or vice versa).
What are the types of Fallacies of Presumption
1) Begging the Question (Petitio Principii)
2) Complex Question
3) False Dichotomy
4) Suppressed Evidence
What are the types of Fallacies of Ambiguity?
1) Equivocation
2) Amphiboly
What are the types of Part/Whole Fallacies?
1) Composition
2) Division
Begging the Question (Petitio Principii)
Assuming as a premise for an argument the conclusion it is intended to prove- often circular. Has two requirements.
1) The argument must be valid.
2) Conceals the questionable character of a key premise (e.g., the premise and conclusion say the same thing in slightly different ways).
Example 1: Clearly, murder is wrong, so euthanasia is morally wrong. [Begs the question: “Is euthanasia a form of murder?”]
Example 2: We can trust our clear and distinct ideas because God exists and isn’t a deceiver. We know God exists and isn’t a deceiver because we can prove that by an argument. That argument is strong because it has premises that are clear and distinct. (Descartes, Meditation III).
16) Complex Question
Such questions presuppose that a definite answer has already been given to a prior question that was not asked.
Example: Have you stopped beating your husband yet? [Presumes an answer to: Were you beating your husband?]
False Dichotomy
Occurs when one premise of an argument is a disjunction that presents two alternatives as if they were jointly exhaustive- the arguer then eliminates an undesirable alternative in order to establish the other as the conclusion.
Example: [Teenage daughter to mother]: Either you’ll let me go to the dance with Fred, or you don’t love me. I know you love me, so you will let me go to the dance with Fred.
Suppressed Evidence
When an arguer ignores evidence that would tend to undermine the premises of an otherwise good argument, causing it to be unsound or uncogent.
Example: It’s a sunny, windless, day at the beach. Must be a great day for a swim. [Ignoring the dorsal fin of a shark swimming right offshore].
Equivocation
Arises when the conclusion of an argument depends on using different meanings of a single word or phrase in the same context.
Example 1: The end of a thing is its perfection. Death is the end of life. Thus, death is the perfection of life.
Example 2: A snail is an animal. Therefore, a fast snail is a fast animal.
Amphiboly
Arguing from premises whose formulations are ambiguous (indeterminate) because of the loose or awkward way in which words are combined- the arguer misinterprets the ambiguity and draws a conclusion based on the faulty interpretation.
Example: Sign- “NO TRESSPASSING VIOLATORS WILL BE PROSECUTED” (So it must be okay to enter this property).
Composition
Arguing that what is true of the parts of a whole (or class) must also be true of the whole itself.
Example: Every student at Smith College is rich, so Smith College must be a rich college.
Division
Arguing that what is true of a whole (or class) must also be true of its parts.
Example: Smith College is a rich college, and Jane goes to Smith, so she must be rich, too.
