Informal Fallacies Flashcards
In what way are informal fallacies flawed?
- they are valid arguments
- flawed due to
(a) pointlessness of the argument
(b) irrelevance of the conclusion
(c) in some cases, falsehood of a premise
Give an example of a ‘begging the question’ argument
(1) The contract between the claimant and the defendant was validly concluded
(2) The contract between the claimant and the defendant was validly concluded
Why are begging the question arguments fallacious?
as they go against the very point of giving arguments (premises) in support of conclusions
What is the technical fault with begging the question arguments?
that they assume what you must prove
Give the three alternative names for a question begging argument
- circular argument
- bootstrapping argument
- petitio principii
Question begging arguments are often hidden, give an example of this
Quinn v Leathem (1901)
What is the straw man fallacy?
it is the fallacy of engaging with - and arguing against - an argument that is not really being endorsed by the other party in the debate, purporting to have thereby refuted the other party’s actual argument
Give a case example where a straw man fallacy arises
Astle v CBRE (2015)
What second fallacy is committed when using a straw man argument?
Irrelevant conclusion
- any argument for a conclusion that is irrelevant for what is being debated commits a fallacy of relevance
- otherwise known as ignoratio elenchi
What is an exhaustive disjunction?
one that leaves no room for another possibility
‘the football team either won, lost or tied’
What is a non-exhaustive disjunction?
leaves room for other possibilities
‘the football team won or lost’
What does the fallacy of false dichotomy rely on?
disjunctions
Give the valid form of disjunctive syllogism
(1) P or q
(2) Not p
(3) Q
An arguer who offers a disjunction syllogism will be asserting the relevant disjunctions as exhaustive, give an example of this
(1) The plantiff was unlawfully dismissed or the plantiff was lying about what happened
(2) It is not the case that the plantiff was unlawfully dismissed
(3) The plantiff was lying about what happened
Why is false dichotomy fallacious
- relies on a disjunction (which the arguer takes to be exhaustive) that is actually false
- as it rules out other relevant possibilities
Define the term ‘tertium quid’
a third thing that is indefinite and undefined but is related to two definite or known things
(there is a…)
In the legal sense, what does a false dichotomy refer to?
(a) the informal fallacy of relying on a disjunction that is wrongly taken to be exhaustive
(b) the formal fallacy of affirming a disjunct
What is a fallacy fallacy?
it is a fallacy to infer, from the fact that a certain argument is fallacious, that its conclusion must be false
Give an example of the fallacy fallacy
(a non sequitur argument)
(1) Argument X is fallacious
(2) The conclusion of argument X is false
- the only thing that follows from (1) is that the proponent of argument X failed to establish its conclusion
- but that does not mean that the conclusion is actually false
Name the four informal fallacies and give a summary of each
- begging the question
(assuming what you need to prove - straw man
(refuting a weaker version of someone’s argument and purporting to have thereby refuted their actual argument - irrelevant conclusion
(presenting an argument for a conclusion whose truth is immaterial for what is at issue) - false dichotomy
(relying on a disjunction that you take to be exhaustive when there are other possibilities that you should’ve taken into account
