Argumentation and Persuasion -- Logical Fallacies Flashcards
What is a logical fallacy?
Defect in an argument which causes it to be invalid or unsound
What are the fallacies of pathos?
Appeal to pity, appeal to ignorance, appeal to traditional wisdom
Appeal to pity (ad misericordium)
Using a statement designed to arouse pity rather than propose a logical argument
example of appeal to pity
if you don’t give me an A i’ll be grounded
appeal to ignorance (ad ignorantium)
concludes a proposition is true because it has not been proven false or that it is false because it has not been proven true
example of appeal to ignorance
ghosts must exist because no one has proven that they do not exist
appeal to traditional wisdom
appeal based on previous actions or precedent (we’ve always done it this way)
example of appeal to traditional wisdom
the city of eugen has kept its urban growth boundary at 6 miles for the past 30 years that has been good enough for 1/3 of a century why should we change it now if it aint broke don’t fix it.
what are the fallacies of ethos
plain folks, ad hominem, ad populum, false authority
plain folks
an appeal trying to win support by appearing to be just like the audience, common man
plain folks example
i know tuition are a bad idea I pay tuition too
ad hominem
against the man (mud slinging/name calling) appeal attacking a person or group, not the issue
example ad hominem
john is a communist what does he know about how to take care of children, Look whos talking
ad populum
to the people, concludes a proposition to be true because many people believe it
ad populum example
85% of consumers purchase PC’s rather than macs all those people can’t be wrong
false authority
citing an expert on one subject as expert on another
false authority example
kevin bacon and michael jordan selling underwear
What are the fallacies of relevance?
Double standard, straw man, red herring, oversimplification, false analogy, glittering generality, Equivocation, false dilemma,
double standard
two comparable items are evaluated according to different standards
double standard example
I know we will hire any man who gets over a 70% on a screening test for hiring post office employees but women should have to get because they often quit the job to take care of children.
Straw man
selecting to refute opponents weakest argument or concocting tenuous opposing arguments
straw man example
Senator jones says that we should not fund the attack submarine program. I disagree entirely I can’t understand why he wants to leave us defenseless likes that
Red herring
diverting attention from important issues by selecting irrelevant issue to discuss
Red herring example
we admit that the measure is popular but we also urge to note that there are so many bond issues on this ballot that the whole thing is getting rediculous
Oversimplification
describing or denying complexity of an issue
Oversimplification example
Murder is wrong. Our problems could be solved by lowering taxes
False analogy
Comparing two items that do not deserve comparison (opposite of double standard)
example of false analogy
Education is like candy a small amount tastes sweet but eat too much and your teeth will rot out likewise more than 2 years of education is bad for a student
Glittering generality
emotionally appealing word or images closely associated with highly valued concepts and beliefs (the words mean different things to different people)
Example of glittering generality
Freedom, patriotism
Equivocation
Using an ambiguous word/phrase/idea and changing its meaning
Equivocation example
A feather is light, what is light cannot be dark, therefore a feather cannot be dark. You say you are for change but your opinions change so much I can’t keep up.
False dilemma
Stating two choices as only alternatives
False dilemma example
America: love it or leave it. you’re either for us or against us, you are part of the solution or you are part of the problem.
Nonsequitor Fallacies
Nonsequitor, Post Hoc, Hasty generalization, Begging the question, slippery slope
Nonsequitor
It does not follow conclusion is not a logical result of facts
Nonsequitor example
if you loved me youd buy me a ham sandwhich. Youve been on a plane for 3 hours you must be hungry
Post hoc (Ergo propter hoc)
After this implying that because one event follows another the first caused the second (Chronology and causality)
Post hoc example
Jane gets a rather large wart on her finger based on a story her father told her she cuts a potato in half rubs it on the wart and then buries it under the light of a full moon over the next few months her wart shrinks and vanishes jane writes to tell her father how right he was about the cure.
Hasty generalization
Drawing conclusions based on insufficient or unrepresentative evidence leads to stereotype.
Hasty generalization example
Men are jerks
Begging the question
Premise is identical with the conclusion
Begging the question example
Free trade will be good for this country. The reason is patently clear. Isn’t it obvious that unrestricted commercial relations will give this nation the benefits of an unimpeded flow of goods between countries.
Slippery slope
One step will eventually lead to an undesirable second or third or fourth
Slippery slope example
If we legalize marijuana the next thing you know we’ll legalize heroin, LSD, and crack cocaine.
