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Logical Fallacies

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Fallacies are errors or flaws in reasoning. Although essentially unsound, fallacious arguments seem superficially plausible and often have great persuasive power. Fallacies are not necessarily deliberate efforts to deceive readers. Writers may introduce a fallacy accidentally by not examining their own reasons or underlying assumptions, by failing to establish solid support, or by using unclear or ambiguous words. Here is a summary of the most common logical fallacies (listed alphabetically):

Begging the question: Arguing that a claim is true by repeating the claim in different words (also called circular reasoning)
Confusing chronology with causality: Assuming that because one thing preceded another, the former caused the latter (also called post hoc, ergo propter hoc— Latin for “after this, therefore because of this”)
Either-or reasoning: Assuming that there are only two sides to a question and representing yours as the only correct one
Equivocating: Misleading or hedging with ambiguous word choices
Failing to accept the burden of proof: Asserting a claim without presenting a reasoned argument to support it
False analogy: Assuming that because one thing resembles another, conclusions drawn from one also apply to the other
Hasty generalization: Offering only weak or limited evidence to support a conclusion
Overreliance on authority: Assuming that something is true simply because an expert says so and ignoring evidence to the contrary
Oversimplifying: Giving easy answers to complicated questions, often by appealing to emotions rather than logic
Personal attack: Demeaning the proponents of a claim instead of refuting their argument (also called ad hominem— Latinfor “against the man”—attack)
Red herring: Attempting to misdirect the discussion by raising an essentially unrelated point
Slanting: Selecting or emphasizing the evidence that supports your claim and suppressing or playing down other evidence
Slippery slope: Pretending that one thing inevitably leads to another
Sob story: Manipulating readers’ emotions to lead them to draw unjustified conclusions
Straw man: Directing the argument against a claim that nobody actually makes or that everyone agrees is very weak