Logic & Debate

logic

the study of reasoning and what makes a valid, sound, good argument

proposition

a statement in an argument asserted to be true or false

argument

the reasoning or set of reasons supporting a claim/statement

explanation

NOT an argument; written to explain something rather than convince an audience

deduction

starts with facts and applies them to reach a conclusion

induction

starts with an observation and leads to a general conclusion

abduction

starts with a set of observations and leads to the most likely explanation

syllogism

a 3-line argument with 2 premises and 1 conclusion

premise

one of the supporting lines for the conclusion; must be true in order for conclusion to be true

conclusion

affirming or denying the proposition

major term

the thing you are affirming or denying

minor term

the subject term of the conclusion

middle term

appearing in both premises but not the conclusion of a syllogism

major premise

premise containing major term

minor premise

premise containing minor term

validity

the logic checks out

sound

the accuracy checks out

causal reasoning

establishing something as causing something else

coincidence

two things that are not related

association

two things share a common aspect

correlation

two things have a mutual relationship

causation

one thing directly caused the other

rhetorical appeals

persuasive techniques authors use to convince audiences

ethos

an appeal to the author’s credibility or character

pathos

an appeal to the reader’s emotions and sympathy

logos

an appeal to logic through facts or statistics

fallacies

flaws in reasoning that lead to unsound arguments

fallacies of relevance

the premises aren’t that related to the conclusion

red herring

something that distracts from the actual main argument

straw man

a more extreme version of your opponent’s argument; putting words in their mouth

ad hominem

attacking the opponent rather than their argument

appeal to force

using threats or strong-arming people into agreeing with you

non sequitur

conclusion doesn’t follow from premises

fallacies of defective induction

premises are relevant but evidence is weak

appeal from ignorance

true because it hasn’t been proven false or false because it hasn’t been proven true

appeal to inappropriate authority

someone bases their argument on authority that they don’t actually have

false analogy

things aren’t actually comparable; apples to oranges

hasty generalization

stereotyping, making a generalization from too small of a sample size

slippery slope

snowballs from one premise to the next to a big conclusion but it’s not actually likely

circular reasoning

using the conclusion as a premise to prove itself true

oversimplification

understating the complexity of an argument to prove your conclusion true