1. From Chapter 4 Philosophy: Questions and Theories
Informal Fallacies
From Chapter 4
Philosophy: Questions and Theories

2. Informal Fallacies three groups
fallacies of relevance, fallacies of presumption, and fallacies of ambiguity

3. Fallacies of Relevance
Appeal to Force (argumentum ad baculum)
Position of power makes threatening statements to force a conclusion
E.g. I’m the teacher and I say that Kim Campbell was the greatest prime minister. Therefore, she is the greatest PM.

4. Fallacies of Relevance
Appeal to Pity (argumentum ad misericordiam)
Force a conclusion by evoking sympathy by focusing on the distressing condition of the speaker or group
E.g. I’m just a teenager whose only method of transport is this skateboard. If you give me this ticket my parents will take this away and then I won’t be able to go to school. Wouldn’t you feel bad? So, you shouldn’t give me a ticket.

5. Fallacies of Relevance
Appeal to Emotion (argumentum ad populum)
Uses emotionally charged language to arouse strong feeling
E.g.: He represents the pride and honour of our beloved Stars and Stripes. So, it is clear why we should vote for him.

6. Fallacies of Relevance
Irrelevant Conclusion
Tries to establish the truth of a proposition by offering an argument that supports a different conclusion
E.g. : Children need attention and working parents don’t have time to give that attention, therefore mothers should stay at home.
This premise supports a conclusion about working parents and not just mothers.

7. Fallacies of Relevance
Appeal to Authority
Opinion of someone famous is offered as a guarantee for truth
Assumes that there is a connection between truth of a statement and the person who asserts or denies it.
E.g.: A Rod says that spiders are insects, therefore they are insects
This can be evidence but never proof

8. Fallacies of Relevance
Attack on the Person
Force the rejection of a conclusion by mounting a personal attack on the person who holds the opinion
E.g. You think that we should have less homework. Well, you are a horrible student, your locker is a mess. So your opinions are not worth considering.

9. Fallacies of Relevance
Appeal to Ignorance
Tries to argue that something is true because it has not been proven false or conversely that something must be false because it has not been proven true
E.g: No one has proven that there is no intelligent life on Mars, so there must be intelligent life there.

10. Fallacies of Presumption
Accident
Starts with a statement that is true as a general rule and applies this principle to a specific case that is out of the norm in some way
E.g.: The rule is always tidy your room. Forget about the fire in the corner, just clean that room.

11. Fallacies of Presumption
Converse Accident
Begins with a specific case that is unusual and derives a general rule from this case
E.g.: He likes cats and is a great pitcher. Therefore, everyone who likes cats is a great pitcher.

12. Fallacies of Presumption
False Cause
Infers a causal connection simply because events seem to be related
E.g.: I watched a movie last night and it gave me a sore throat. Therefore I will not watch movies anymore because I don’t like sore throats.

13. Fallacies of Presumption
Begging the Question
Bases the conclusion of an argument on a premise or premises that need to be proven as much as the conclusion
E.g.: Capital punishment is necessary and therefore people who kill others in car crashes should be executed
uses circular reasoning
E.g.: Murders have lost the right to live because anyone who kills someone has lost that right.

14. Fallacies of Presumption
Complex Question
Presupposes the truth of the conclusion by putting it in the premise of the argument
E.g.: Have you stopped overeating? No? Then you are clearly still overeating.

15. Fallacies of Ambiguity
Equivocation
Use an ambiguous word or phrase in two or more ways in the same argument
E.g.: Really exciting books are rare and rare books are expensive. So, exciting books must be expensive.

16. Fallacies of Ambiguity
Amphiboly
Construction of a sentence creates ambiguity
E.g. That store carries jeans for people with 32 waists. I only have one waist so I won’t be shopping there.

17. Fallacies of Ambiguity
Composition
Drawing a conclusion about a whole or a group based on the features of its parts
E.g.: You like pickles, marshmallows and jello, therefore you will love the pickle, marshmallow and jello sandwich I made you for lunch.

18. Fallacies of Ambiguity
Division
Drawing a conclusion about a part based on the whole.
E.g. They live in a neighbourhood with nice houses, therefore their house must be nice.