Fallacy

Fallacy: A counterfeit argument.

• Appears to be valid at a first glance.

A. Fallacies of Relevance

1. Subjectivism: I believe/want p to be true, therefore p.
   • Examples:
     • “God must exist because I couldn’t live if he didn’t”
     • “Barbie (2023) is a great movie because it made me laugh and kept my interest”
     • “My brother would never do that.”
     • “This person is guilty because I think they look suspicious”,
   • aka: Fallacy of Appeal to One’s Own Emotions/Beliefs
2. Appeal to Majority: A majority thinks p is true, therefore p.
   • Examples:
     • “Buying slaves is good because nearly every successful country bought slaves.”
     • “All the other countries are providing universal healthcare, and therefore the US should too.”
     • “A majority of Americans believe we should kill homeless people for sport.”
     • “This product gets 5 stars, so it must be good”
3. Appeal to Audience Emotion: Lots of emotional language but no evidence, therefore p.
   • Examples:
     • “We must kick out the rapists and murders crossing the border”
     • “They are stealing hardworking American’s jobs”
   • aka: Appeal to the mob (Ad Populum), Appeal to Pity
4. Appeal to Force: I’ll do something bad to you if you don’t accept p, therefore p is true.
   • Examples:
     • “If you write something that I disagree with, I will grade you harshly”
     • “This is a good rule because you’ll be punished if you don’t follow it”
5. Ad Hominem: A bad person is advocating p, therefore p is false, or their argument is bad.
   • Examples:
     • “Don’t vote for this proposition because trial lawyers support it”
     • “You’re just saying that because you own a daycare”
   • Special Case: Poisoning the Well (argument is bad because proposer has a vested interest)
   • Special Case: You, Too Fallacy (you also do this)
   • Special Case: Abusive ad hominem

B. Inductive Fallacies

6. Appeal to Authority: A respected person says p, therefore p.
   • Note: Only a fallacy if the person fails tests for reliable testimony.
   • Examples:
     • “It’s true because it’s in the Bible.”
7. False Dichotomy: Either p or q. Not q, therefore p.
8. Post hoc: p came before q, therefore p caused q.
   • Note: This is a special case of correlation \ne causation
9. Hasty Generalization: One or a few things show p, therefore p
10. Accident: We have a generalization and falsely apply it to prove p
    • Note: This is the reverse of hasty generalization (hasty instantiation?)
    • Example:
      • “A player has 20 seconds to serve starting from the end of the last point in a Tennis game. The player fell down and got injured in the last point and 20 seconds have passed, therefore that player has lost a point.”
11. Slippery Slope: Action P \to Q \to R \to S, therefore we shouldn’t do P.

C. Fallacies of Presumption and Diversion

12. Circular Argument: p is true because it’s true
13. Equivocation: … W … is true because ….W … (where W has two different meanings)
14. Appeal to Ignorance: p is true because you haven’t disproved p
    • Why: The burden of proof is on the person making the claims.
15. Diversion: S is true because I can prove T
16. Straw Man: S is false because I can disprove T
    • Note: A special version of diversion.