What is a fallacy?
A fallacy is a type of argument that may seem to be correct, but on closer examination proves to be incorrect.
The fallacy of affirming the consequent
The fallacy of denying the antecedent
Three fallacies of presumption
- Complex question
- Begging the question
The fallacy of accident
A fallacy of presumption in which a generalization is applied to individual cases that it does not govern.
The fallacy of the complex question
A fallacy of presumption in which one presupposes the truth of a proposition buried in the question.
The fallacy of begging the question
A fallacy of presumption in which the conclusion is stated or assumed in one of the premises.
Five fallacies of ambiguity
The fallacy of equivocation
A fallacy of ambiguity in which two or more meanings for same word or phrase have been confused for each other.
The fallacy of amphiboly
A fallacy of ambiguity in which a grammar problem leads to alternate possible meanings.
The fallacy of accent
A fallacy of ambiguity in which the meaning of a term in the conclusion does not equal its meaning in the premise, because of a change of emphasis.
The fallacy of composition
A fallacy of ambiguity involving a mistaken inference, in which what is true of the parts are taken to be true of the whole.
The fallacy of division
A fallacy of ambiguity involving a mistaken inference, in which what is true of the whole is taken to be true of the parts.
Six fallacies of relevance
- Appeal to emotion / appeal to the populace
- Red herring
- Straw man
- Ad hominem
- Appeal to force
- Missing the point
The fallacy of appeal to emotion / appeal to the populace (ad populum)
When correct reasoning is replaced by devices calculated to elicit emotional and nonrational support for the conclusion urged.
The fallacy of red herring
When correct reasoning is manipulated by the introduction of some event or character that deliberately misleads the audience and thus hinders rational inference.
The fallacy of straw man
When correct reasoning is undermined by the deliberate misrepresentation of the opponent’s position.
The fallacy of ad hominem
When correct reasoning about some issue is replaced by an attack upon the character or special circumstances of the opponent.
The fallacy of appeal to force (ad baculum)
When reasoning is replaced by threats in the effort to win support or assent.
The fallacy of missing the point (ignoratio elenchi)
When correct reasoning is replaced by the mistaken refutation of a position that was not really at issue.
Four fallacies of defective induction
- Argument from ignorance
- Appeal to inappropriate authority
- False cause
- Hasty generalization
The fallacy of argument from ignorance (ad ignorantiam)
When it is argued that a proposition is true on the grounds that it has not been proved false, or when it is argued that a proposition is false because it has not been proved true.
The fallacy of appeal to inappropriate authority (ad verecundiam)
When the premises of an argument appeals to the judgment of some person or persons who have no legitimate claim to authority in the matter at hand.
The fallacy of false cause
When one treats as the cause of a thing that which is not really the cause of that thing, often relying (as in the subtype post hoc ergo propter hoc) merely on the close temporal succession of two event.
The fallacy of hasty generalization (converse accident)
When one moves carelessly or too quickly from one or a very few instances to a broad or universal claim.
Four types of fallacies
- Fallacies of relevance
- Fallacies of defective induction
- Fallacies of presumption
- Fallacies of ambiguity
What is “tu quoque”?
Tu quoque is a kind of circumstantial ad hominem attack, used by the speaker to defend himself/herself by essentially saying, “Look who’s talking.”
“Jump on the bandwagon” is a kind of ____________ fallacy.
The bandwagon fallacy is a kind of ad populum (appeal to the populace) fallacy.
Ad misericordiam is a kind of _____________ fallacy.
Ad misericordiam (appeal to pity) is a kind of ad populum (appeal to the populace) fallacy.
Guilt by association is a kind of _____________ fallacy.
Guilt by association is a kind of abusive ad hominem fallacy.
Poisoning the well is a kind of _______________ fallacy.
- Poisoning the well is a kind of circumstantial ad hominem fallacy.
- It is used to suggest that an opponent’s position should be rejected because the opponent has warped judgment in general.
- Ex: Claiming that Tom Cruise’s opinions on any topic should not be trusted because, as a Scientologist, he believes in aliens.
What does ad baculum mean?
- Appeal to the stick!
- It’s the name of the appeal to force fallacy.
Consider: “An elephant is an animal; therefore, a small elephant is a small animal.” Is this a fallacy, and if so, which one?
It is a fallacy of equivocation, because the word “small” is relative. A small elephant is still a large animal.
Consider: “An elephant is an animal; therefore, a gray elephant is a gray animal.” Is this a fallacy, and if so, which one?
It is not a fallacy. “Gray” is not a relative term, so it means the same thing in both instances of its use here.
Consider: “Women prefer democrats to men.” Is this a fallacy, and if so, which one?
It is a fallacy of amphiboly, because its grammatical error gives two possible meanings: either (1) women prefer democrats over men, or (2) women, not men, prefer democrats.
Consider: “Dr. Salick donated, along with his wife, Gloria, $4.5 million to Queens College for the center.” Is this a fallacy, and if so, which one?
It is a fallacy of amphiboly, because its grammatical error gives two possible meanings: either (1) Dr. Salick and his wife donated money, or (2) Dr. Salick donated his wife and his money to the center.
Consider: “We should not speak ill of our friends.” Is this a fallacy, and if so, which one?
It is a fallacy of accent, because a change in emphasis can give different meanings, for instance: (1) we should not say bad things about our friends, (2) we may say bad things about other people, but not our friends, or (3) we may write bad things, but not say bad things, about our friends.
When a person’s words are taken out of context so that they appear to mean something other than they did when they were originally spoken, what kind of fallacy is this?
It is a fallacy of accent, because words taken out of context have a different emphasis than they do in context.