Most important fallacies / flaws in reasoning

equivocation

sliding between two or more different meanings of a single word or phrase that is important to the argument

conflation

bring 2 or more different concepts together and treating them as the same thing

circular argument

an argument that begs the question relies on a premise that says the same thing as the conclusion (you might hear being referred to as “being circular” or “circular reasoning”

begging the question

it occurs when the premises that are meant to support the argument already assume that the conclusion is true. If you start from a place where the conclusion being argued is already assumed true, then you’re not making an argument at all

invalid deduction

a deductive argument where the conclusion does not necessarily follow from the premises. The premises/reasons can be true, but the conclusion based on those reasons is false

causal flaw / post hoc / false cause

when an arguer assumes, without adequate reason, that because one event precedes another, that the first event was the cause of the second

rash / hasty generalization

occurs when an arguer draws a general, overall conclusion, from a sample too biased or too small

sweeping generalization

the reasoning moves from some or many to all; moves from the sweeping, stereotypical, conclusion back to the individual

restriction of options (false dichotomy)

The arguer sets up the situation so it looks like there are 2 options. The arguer then eliminates one choice, so it appears that we only have one choice: the one they wanted us to pick in the first place

confusion of necessary and sufficient conditions

a necessary condition is something which must happen in order for something else to happen, and a sufficient condition is something which in must happen in order to be certain something else will happen

slippery slope

when the arguer claims, without sufficient reason, that a seemingly harmless action will lead to a disastrous outcome

personal attach / ad hominem

rejects someone’s argument or claim by attacking the person rather than the person’s argument or claim

counter-attack / tu quoque

an arguer rejects another persons argument or claim because that person fails to practice what he or she preaches

straw man

the arguer sets up a wimpy version of the opponents position and tries to score points by knocking it down