Ad hominem
Attacking the person instead of the reasons.
Character can sometimes be relevant to trust, but insults and irrelevant personal facts do not refute a claim. Separate the speaker from the argument's merits.
Reference
Glossary
Shared vocabulary for Think Straight, Argue Better and Think Smart, Argue Fair. Each term links to a drill when one exists.
Argument
A conclusion supported by reasons (premises), not a yelling match.
In ordinary speech, argument means a fight. In logic, an argument is a set of premises offered as reasons for a conclusion. Assertions without reasons are not arguments; neither are mere descriptions. The practical test: can you state what the person wants you to believe and why?
Burden of proof
Who must provide reasons for a claim.
Usually the person making a contested claim bears the burden. Shifting burden (prove me wrong) is a common rhetorical move. Ask what would count as enough evidence either way.
Conclusion
What the arguer wants you to accept.
Find the conclusion by asking: what is this person trying to convince me of? Everything else is either support, distraction, or framing. Mapping puts the conclusion at the top so premises can be checked underneath.
Enthymeme / hidden assumption
An argument with an unstated premise.
Most real arguments skip steps. Ask: what would I have to believe for this to work? Writing that missing premise lets you accept, reject, or refine it instead of arguing past each other.
Ethos
Appeal to credibility or character.
Relevant expertise strengthens ethos; fame alone does not. Check whether the speaker's authority matches the topic.
False dilemma
Presenting only two options when more exist.
Either/or framing can be honest when options truly exhaust the space. Often it erases middle paths. Ask for a third option before choosing sides.
Hasty generalization
Drawing a big conclusion from too small a sample.
Two anecdotes are not a survey. Ask what sample would be enough, and whether selection bias shaped what you saw.
Inductive reasoning
Reasons that make a conclusion probable, not guaranteed.
Induction includes generalizations, analogies, and causal inferences from samples. Judge these arguments as strong or weak. Demanding deductive certainty from inductive claims is itself a confusion of standards.
Logos
Appeal to logic and evidence.
Data, valid inference, and clear definitions are logos. Logos can still fail if evidence is cherry-picked or the form is invalid — so pair it with fallacy checks.
Pathos
Appeal to emotion.
Emotion can illuminate values and urgency. It becomes manipulative when it replaces reasons for a factual claim or shames people into agreement.
Premise
A reason offered in support of a conclusion.
Premises are the supporting claims. They can be true or false; evaluating them is separate from asking whether they would support the conclusion if true. Hidden premises (enthymemes) are often where disagreements actually live.
Principle of charity
Interpret unclear claims in their strongest reasonable sense.
Charity is not agreement. It is a discipline against cheap wins from misreading. Pair it with steel-manning when stakes are high or language is messy.
Slippery slope
Claiming a small step must lead to disaster without showing the chain.
Slopes can be real when mechanisms are specified. The fallacy is the leap. Demand the intermediate steps and evidence for each.
Socratic method
Using questions to clarify and test claims.
Clarify terms, surface assumptions, assign burden of proof, and explore consequences before launching a rebuttal. Questions are tools, not traps, when paired with charity.
Sound
Valid and the premises are actually true.
Soundness is the gold standard for deductive arguments: the structure works and the reasons are true. If either fails, do not treat the conclusion as established by that argument alone.
Steel-manning
Stating the other side in its strongest fair form before responding.
The opposite of a straw man. Steel-manning builds intellectual honesty and often improves your rebuttal. If your opponent would not recognize the paraphrase, keep revising before you attack.
Straw man
Twisting someone's view into a weaker version that is easier to attack.
Also called twisting words in the kids' book. Fix: restate the strongest fair version (steel-man), then respond. If you need to distort to win, your case is weak.
Valid
If the premises were true, the conclusion must follow.
Validity is about logical form, not whether the premises are true in the real world. A valid argument with a false premise is still valid — but not sound. Confusing validity with truth is a common beginner mistake.