Logical Fallacies

ad hominem

a fallacy that attacks the person rather than dealing with the real issue in dispute

ad populum

This fallacy occurs when evidence boils down to "everybody's doing it, so it must be a good thing to do."

appeal to tradition

a fallacy which assumes that something old is automatically better than something new

begging the question

A fallacy in which a claim is based on evidence or support that is in doubt.

deduction

the process of moving from a general rule to a specific example

equivocation

the use of ambiguous language to conceal the truth or to avoid committing oneself; prevarication

false analogy

When two cases are not sufficiently parallel to lead readers to accept a claim of connection between them.

false dilemma

A fallacy of oversimplification that offers a limited number of options (usually two) when in fact more options are available.

hasty generalization

A fallacy in which a faulty conclusion is reached because of inadequate evidence.

induction

the process that moves from a given series of specifics to a generalization

non-sequitur

A statement that does not follow logically from evidence

Occam's razor

a problem-solving principle that suggests the simplest explanation, or the one with the fewest assumptions, is often the best one to consider first when evaluating competing hypotheses

post hoc, ergo propter hoc

it is incorrect to always claim that something is a cause just because it happened earlier; correlation does not imply causation.

red herring

A fallacy that introduces an irrelevant issue to divert attention from the subject under discussion

reductio ad absurdum

it reduces an argument to an either/or choice

slippery slope

A fallacy that assumes that taking a first step will lead to subsequent steps that cannot be prevented

straw man

A fallacy that occurs when a speaker chooses a deliberately poor or oversimplified example in order to ridicule and refute an idea.

syllogism

A form of deductive reasoning consisting of a major premise, a minor premise, and a conclusion.