Fallacies Master Set

Confusing Necessary and Sufficient Conditions

Occurs when someone assumes a necessary condition is enough to guarantee an outcome. Example: "I filled out the visa form, so I'll definitely get approved."

Necessary Condition

Something that must be present for an event to occur, but alone doesn't cause it. Example: Qualifying for the World Cup is necessary to win it.

Sufficient Condition

Something that guarantees the outcome. Example: Winning the final game is sufficient to win the World Cup.

Slippery Slope

Claims a harmless action will lead to extreme consequences. Example: "If you don't take calculus, you won't go to college, and you'll end up homeless."

Ad Hominem (Personal Attack)

Rejects a claim by attacking the person instead of the argument. Example: "Don't listen to him; he's immature."

Tu Quoque (You Too / Counterattack)

Rejects a claim because the speaker doesn't practice what they preach. Example: "Doctor says quit smoking." "You smoke too!"

Straw Man

Misrepresents someone's argument to make it easier to attack. Example: "She wants cleaner energy, so she must want to shut down all jobs."

False Cause (Post Hoc)

Assumes one event caused another because it happened first. Example: "I drank tea and got better — tea cured me."

Hasty Generalization

Draws a broad conclusion from too small or biased a sample. Example: "I met three rude New Yorkers, so all New Yorkers are rude."

Sweeping Generalization (Stereotyping)

Applies a general rule to everyone or to an individual. Example: "Everyone from Tampa is tall, so you must be tall."

False Dichotomy (Either-Or Fallacy)

Presents only two options when others exist. Example: "Either we tear down the building or risk safety."

Affirming the Consequent

Invalid deduction: If A → B; B → therefore A. Example: "If I have the flu, I have a fever. I have a fever, so I must have the flu."

Denying the Antecedent

Invalid deduction: If A → B; not A → not B. Example: "If I clean, I'm not reading. I'm not cleaning, so I'm reading."

Equivocation

Uses one word with two meanings in the same argument. Example: "Charity is the right thing to do, so charities have a right to our money."

Conflation

Treats two different ideas as identical. Example: "Space tourism and space exploration are the same."

Circular Argument

Repeats the same point as proof. Example: "Tempus Fugit makes the best watches because they're the greatest."

Begging the Question

Assumes the conclusion is already true.

Inappropriate Appeal to Authority

Uses a non-expert as an expert. Example: "A TV actor recommends this medicine, so it works."

Bandwagon Appeal (Appeal to Popularity)

Says something is true or good because everyone believes it. Example: "All my friends have piercings, so I should too."

Appeal to Emotion

Uses pity, fear, or guilt instead of logic. Example: "Don't fail me; my pet died."

Appeal to Tradition

Argues something is right because it's always been done. Example: "We've always done car washes for prom."

Appeal to Novelty

Claims something new is better just because it's new. Example: "The latest diet is the best."

Ad Hominem vs Tu Quoque

Ad Hominem = attacks person; Tu Quoque = calls them hypocrite.

Bandwagon vs Appeal to Authority

Bandwagon = popular opinion; Authority = supposed expert opinion.

False Cause vs Hasty Generalization

False Cause = wrong link between events; Hasty Generalization = wrong conclusion from small data.

Appeal to Emotion Example (Guilt)

"If you don't donate, think of the poor children!"

Appeal to Emotion Example (Pity)

"Don't fire me; my cat is sick."

Appeal to Tradition Example

"Our ancestors did it this way, so it's right."

Appeal to Novelty Example

"We need new tech—it's newer, so it's better."

Circular Reasoning Example

"I'm trustworthy because I always tell the truth."

Begging the Question Example

"We must have free speech because people should be able to say what they want."

Equivocation Example (Faith)

"The priest told me to have faith, and I have faith my son will do well."

Conflation Example (Health)

"Obesity is caused by lack of fitness, so all overweight people are unfit."

Ad Hominem Example (Person Attack)

"Don't listen to her argument—she failed math once."

Tu Quoque Example (Hypocrisy)

"You tell me to study, but you never did!"

False Dichotomy Example

"Either you're with us or against us."

Affirming the Consequent Example

"If it rains, the streets are wet. The streets are wet, so it must have rained."

Denying the Antecedent Example

"If I study, I'll pass. I didn't study, so I failed."

False Cause Example

"Every time I wear red, I win—red brings luck."

Hasty Generalization Example

"Three people I know are rude, so everyone is rude."

Sweeping Generalization Example

"All teens are careless. You're a teen, so you're careless."

Appeal to Emotion (Fear)

"If you don't vote for me, the world will end."