Fallacies

Question 1

Define fallacy

Answer 1

A fallacy is a mistake in reasoning

Question 2

Define formal fallacy

Answer 2

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

Question 3

Outline the 5 main formal fallacies

Answer 3

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.

Question 4

Define informal fallacy

Answer 4

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

Question 5

State acronym for remembering formal fallacies

Answer 5

CADCU

Question 6

State the three types of informal fallacies

Answer 6

fallacies of relevance
fallacies of presumption
fallacies of ambiguity

Question 7

Define fallacies of relevance

Answer 7

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

Question 8

State the main fallacies of relevance

Answer 8

ad hominem e.g. tu quoque

ad ignorantiam

ad verecundiam

ad populum

ad misericordiam

ad baculum

ignoratio elenchi

Question 9

Define ad hominem fallacy

Answer 9

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

Question 10

Define tu quoque fallacy

Answer 10

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

Question 11

Define ad ignorantiam fallacy

Answer 11

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

Question 12

Define ad verecundiam fallacy

Answer 12

ad verecundiam: appeal to inappropriate authority

Question 13

Define ad populum fallacy

Answer 13

ad populum: appeal to the majority

Question 14

Define ad misericordiam fallacy

Answer 14

ad misericordiam: appeal to pity

Question 15

Define ad baculum fallacy

Answer 15

ad baculum: appeal to force

Question 16

Define ignoratio elenchi fallacy

Answer 16

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

Question 17

Define fallacies of presumption

Answer 17

fallacies of presumption occur when an argument relies on unjustified assumptions

Question 18

State the main fallacies of presumption

Answer 18

complex question

false dilemma/dichotomy

petitio principii

post hoc ergo propter hoc.

accident

converse accident

Question 19

Define complex question

Answer 19

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

Question 20

Define false dilemma/dichotomy

Answer 20

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.”

Question 21

Define petitio principii

Answer 21

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

Question 22

Define post hoc ergo propter hoc.

Answer 22

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.”

Question 23

Define accident

Answer 23

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.

Question 24

Define converse accident

Answer 24

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

Question 25

Define fallacies of ambiguity

Answer 25

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

Question 26

State the main fallacies of ambiguity

Answer 26

equivocation

amphiboly

accent

Question 27

Define equivocation fallacy

Answer 27

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.

Question 28

Define fallacy of amphiboly

Answer 28

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

Question 29

Define fallacy of accent

Answer 29

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.

Question 30

State 5 other fallacies worth knowing

Answer 30

straw man

genetic fallacy

argument to moderation

gambler’s fallacy

slippery slope fallacy

Question 31

Define straw man fallacy

Answer 31

straw man: reconstructing an opponent’s argument into something more easy to refute whilst maintaining that you have refuted their original argument.

Question 32

Define genetic fallacy

Answer 32

the genetic fallacy: equating the origin of a belief with the justification of a belief. It might then seem that by criticising the origin of a belief we have defeated the truth of a person’s claim. But what about any independent justifications they might have?

Question 33

Define argument to moderation

Answer 33

argument to moderation: assuming that the compromise between two positions is always correct.

Question 34

Define gamblers fallacy

Answer 34

gambler’s fallacy: belief that independent events can affect the likelihood of each other.

Question 35

Define slippery slope fallacy

Answer 35

slippery slope fallacy: A leads to B, B leads to C, C leads to…, …leads to Z. A leads to Z.