Logical fallacies · 71

Rejects a claim by attacking the person who makes it (their character, motives or circumstances) instead of addressing the reasoning or evidence.

Answers a criticism by pointing out that the critic does, or once did, the same thing.

Discredits a claim or a person because of a supposed link to someone or something disliked.

Judges a claim good or bad because of where it came from rather than on its present merits.

Dismisses a claim by speculating about the motives of the person making it instead of examining the evidence.

Discredits a person in advance so that anything they later say will be dismissed.

Misrepresents someone's position, usually by exaggerating, oversimplifying or distorting it, and then attacks that weaker version instead of what they actually said.

Responds to an accusation or question by raising a different, usually unrelated, wrong done by someone else ("what about...?").

Introduces an irrelevant topic to divert attention from the issue under discussion.

Changes the criteria for proof or success after the original demand has been met, so the claim can never be satisfied.

Demands that others disprove a claim instead of supporting it with evidence.

Protects a generalization from a counterexample by redefining the group so the counterexample no longer counts ("no real X would do that").

Asks a question that contains an unproven or contested assumption, so any direct answer seems to accept it.

Dismisses a position by mocking it or presenting it as absurd instead of showing that it is wrong.

Overwhelms an opponent with a rapid stream of many weak or misleading points that take far longer to refute than to assert.

Dismisses a point because of the way it is expressed (angry, emotional, impolite) rather than because of its content.

Switches between a bold, contested claim (the bailey) and a modest, easily defended one (the motte): retreating to the modest claim when challenged, then acting as if the bold claim had been established.

Applies a standard to everyone else but claims an unjustified exception for one's own case.

Offers an argument that may be sound but proves something other than the point at issue.

Tries to win agreement by stirring feelings (fear, anger, pity, pride) instead of offering evidence or reasons.

Treats a claim as true because an authority or expert says so, especially when the authority is irrelevant, anonymous, disputed by other experts, or speaking outside their field.

Argues that a claim is true or a choice is good because many people believe it or do it.

Argues that something is good, safe or right because it is "natural" (or bad because it is "unnatural").

Argues that something is right or better because it has long been done or believed.

Tries to persuade by raising fear of a threat, often exaggerated, rather than showing that the claim is true or the proposal effective.

Claims something is true because it has not been proven false, or false because it has not been proven true.

Rejects a claim because the speaker finds it hard to imagine or understand.

Argues that something is better simply because it is new or modern.

Seeks agreement by evoking sympathy for a person or group in place of evidence about the merits of the claim.

Argues that a claim is true or false because of the good or bad consequences of believing it, rather than because of the evidence.

Decides what is true on the basis of what one wants to be true.

Draws a conclusion from the absence of evidence, such as a source not mentioning something.

Persuades by praising the audience rather than supporting the claim.

Presents only two options when more exist, so that rejecting one seems to force acceptance of the other.

Claims that one step will inevitably lead to extreme consequences without showing that each step in the chain is likely.

Assumes in its premises what it is supposed to prove, so the argument goes in a circle.

Treats two things as equal because they share some feature, ignoring large differences in degree or kind.

Draws a conclusion that does not follow from the premises.

Argues that two things are alike in one respect and so must be alike in another, though they differ in ways that matter.

Assumes the truth must lie between two opposing positions.

Concludes that a claim is false because an argument offered for it was fallacious.

Assumes that what is true of the parts is true of the whole.

Assumes that what is true of the whole is true of each of its parts.

Treats a claim as established by repeating it often.

Slips from a description of how things are to a claim about how they should be, without stating the value judgement that bridges the two.

Rejects a realistic option because it is not perfect, while ignoring that the alternative is worse.

Rejects a distinction because there is no sharp boundary between the extremes ("there is no exact point where a man becomes bald, so nobody is bald").

Infers that something is the case because it would be good (or is not the case because it would be bad), the mirror image of the is-ought slip.

Presents only the evidence that supports a conclusion and ignores or hides the rest.

Assumes that because one event followed another, the first caused the second.

Concludes that one thing causes another because they occur together.

Draws a broad conclusion from too few or unrepresentative cases.

Uses a personal story or isolated example in place of systematic evidence.

Believes that past random outcomes change the odds of the next one ("it's due").

Attributes an outcome to one cause when it had several that interacted.

Judges a combination of events as more probable than one of them alone, though a conjunction can never be more likely than either part.

Picks the hypothesis after looking at the data, like firing at a barn wall and then drawing the target around the bullet holes.

Believes that someone on a winning streak is more likely to keep winning in situations where outcomes are largely independent.

Confuses the probability of the evidence given innocence with the probability of innocence given the evidence.

Draws conclusions about individuals from statistics about the group they belong to.

Refuses to accept a conclusion that strong evidence supports, attributing it to coincidence or chance.

Assumes that because something could happen it will happen, or must happen.

Uses a word in two different senses within one argument so that the conclusion seems to follow.

Uses vague wording ("some say", "studies show", "many experts") that suggests support without naming who or what it is.

Treats an abstraction as if it were a concrete thing with its own will or agency.

Argues that a word's present meaning must be its original or "true" meaning.

Relies on a sentence whose grammar allows more than one reading, then treats the convenient reading as the intended one.

Reasons "If A then B; B; therefore A".

Reasons "If A then B; not A; therefore not B".

Concludes that two categories overlap because both overlap with a third: "All A are C; all B are C; therefore all A are B".

Reasons "A or B; A; therefore not B", treating an inclusive "or" as if it were exclusive.