Propositions
statements that are true or false. ex. 1+1=2
Non-Propositions
statement that cannot be true or false. EX. Lets go fly a
... [Show More] kite
Simple propositions
simply true or false on their own.
Complex propositions
Truth depends on the truth of their parts and their internal logic. ex. this soda is coke or pepsi.
Words used to identify Independent Propositions
and
or
either.....or.....
but
if.....then......
Bad inferential structure
argument is bad, because the premises dont support the conclusion.
False Premise
One premise has to be false in argument. ex. All humans are cats (false) All cats are mammals (True) So, all humans are mammals (True)
Conclusion Indicators
trying to get me to believe something, that is the conclusion
Premise Indicators
indicating that the fact said lead to a conclusion
Because, for, given that, in fact, as, since, as indicated by
Premises make you ask
"what does that mean?" "why tell me that?"
Conclusions make you ask
"why would i believe that? Give me a reason to believe that claim"
Deduction
arguments where the premises guarantee or necessitate the conclusion
Induction
arguments where the premises make the conclusion probable
Abduction
finding the most likely explanation for what has happened
Truth
a true statement that accurately represents reality. EX. P1) all siamese are cats. P2) Rosie is a siamese. C) therefore, Rosie is a cat.
validity
If premises are true, the conclusion must be true. EX. P1) Rosie was born in Cali. P2) Everyone from Cali likes biscuits C) Rosie likes biscuits
Soundness
premises are true and conclusion makes sense EX. P1) Whales dont have fur. P2) Whales are mammals. C) Therefore, not all mammals have fur
Cogency
cogent if its Strong & Premises are true. EX. most crows seen are black. Therefore, the next crow seen will be black.
Formal Fallacy
argument with a bad structure
informal fallacy
content of argument is the issue
modus pones
if a, then b
a
therefore, b EX. if Today is Tuesday, then John will go to work. Today is Tuesday. Therefore John will go to work.
modus tollens
if a, then b
not a
therefore, not b EX. If im happy, then i smile. Im not smiling, therefore im not happy
fallacy fallacy
someone notices your argument contains a fallacy, leads them to believe your claim is false. EX. your argument contains a straw man fallacy so i think youre lying.
ad hominem fallacy
attacking person, not the argument EX. 1) cats are smart animals. 2. well you're stupid so i dont believe you.
genetic fallacy
arguer critiques origin of claim or argument rather than the argument EX. my parents told me that God exists, therefore, God exist.
straw figure or straw man fallacy
arguing against a false version of someones actual argument. EX. 1) id rather have a dog than a cat. 2) why do you hate cats?
red herring fallacy
talk about one thing, but end up talking about another EX. you are home late, you distract parents by asking how the weather is.
evasive red herring
responding to a question with something off the topic
Appeal to Authority fallacy
believing an argument because of someone's authority EX. kid says cussing is wrong cause his mom said so.
Appeal to Force
uses threat to make someone believe argument EX. cats are cute, you better believe me or ill punch you in the face.
Ad Populum fallacy
believing an argument because it's popular EX. everyone drives over the speed limit, so its should not be against the law.
Appeal to Consequences fallacy
statement must be T or F based on the consequences if would lead to. EX. stock market will go up this year. A lot of people would lose money if it didn't.
Equivocation fallacy
using same word in more than one way. Causing a misleading argument.
example: children are a headache. Aspirin will make headaches go away. Therefore, aspirin will make children go away [Show Less]