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Flashcards in Fallacies Deck (35)
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1

Define fallacy

A fallacy is a mistake in reasoning

2

Define formal fallacy

A formal fallacy is an inference rendered invalid by a flaw in its syntax (form)

3

Outline the 5 main formal fallacies

affirming the consequent: p —> q, q, therefore p.
denying the antecedent: p—> q, -p, therefore -q.
affirming a disjunct: p v q, p, therefore -q.
denying a conjunct: -(p ^ q), -p, therefore q
undistributed middle: p —> q, r —> q, therefore r —> p.

4

Define informal fallacy

An informal fallacy is a type of mistake in reasoning that arises from the mishandling of the content of the propositions constituting the argument

5

State acronym for remembering formal fallacies

CADCU

6

State the three types of informal fallacies

fallacies of relevance
fallacies of presumption
fallacies of ambiguity

7

Define fallacies of relevance

fallacies of relevance occur when the premises of an argument are not relevant to the conclusion

8

State the main fallacies of relevance

ad hominem e.g. tu quoque

ad ignorantiam

ad verecundiam

ad populum

ad misericordiam

ad baculum

ignoratio elenchi

9

Define ad hominem fallacy

argument directed not at the conclusion, but at the person who holds it

10

Define tu quoque fallacy

tu quoque: a person’s argument is wrong (unsound?) because they don’t act in accordance with it

11

Define ad ignorantiam fallacy

ad ignorantiam: a proposition is true (or false) because not yet proved otherwise

12

Define ad verecundiam fallacy

ad verecundiam: appeal to inappropriate authority

13

Define ad populum fallacy

ad populum: appeal to the majority

14

Define ad misericordiam fallacy

ad misericordiam: appeal to pity

15

Define ad baculum fallacy

ad baculum: appeal to force

16

Define ignoratio elenchi fallacy

ignoratio elenchi (irrelevant conclusion): premises are irrelevant to conclusion

17

Define fallacies of presumption

fallacies of presumption occur when an argument relies on unjustified assumptions

18

State the main fallacies of presumption

complex question

false dilemma/dichotomy

petitio principii

post hoc ergo propter hoc.

accident

converse accident

19

Define complex question

complex question: asking a question in such a way as to presuppose the truth of some conclusion. “Have you stopped beating your wife yet?”

20

Define false dilemma/dichotomy

false dilemma/ dichotomy: two alternative statements are held to be the only possible options when in reality there are more e.g. “I thought you were a good person, but you weren’t at church today.”

21

Define petitio principii

petitio principii (begging the Q): assuming the truth of what you intend to prove in order to prove it.

22

Define post hoc ergo propter hoc.

post hoc ergo propter hoc.: after the fact, therefore because of that fact. “The bigger a child's shoe size, the better the child's handwriting. Therefore, having big feet makes it easier to write.”

23

Define accident

accident: presume the applicability of a generalisation to individual cases that the generalisation does not cover. E.g., inferring that penguins can fly from the fact they are birds.

24

Define converse accident

converse accident: Presume that what is true of a particular case is true of some generalisation of cases. Hasty generalisation.

25

Define fallacies of ambiguity

fallacies of ambiguity occur in arguments that rely on a term or phrase having multiple meanings in multiple propositions within the argument

26

State the main fallacies of ambiguity

equivocation

amphiboly

accent

27

Define equivocation fallacy

equivocation: argument relies on confusing the multiple meanings of the same word or phrase. “This Lloyds branch is a bank. Banks are next to rivers. Therefore, we must be next to a river.

28

Define fallacy of amphiboly

amphiboly: ambiguity is due to grammatical form. “The panda eats shoots and leaves.”

29

Define fallacy of accent

accent: ambiguity is due to differing stress on the same word or phrase. E.g., “I didn't take the test yesterday” stressed in six different places.

30

State 5 other fallacies worth knowing

straw man

genetic fallacy

argument to moderation

gambler's fallacy

slippery slope fallacy