A logical fallacy is a flaw in reasoning.
Strong arguments are based on testable premises and logical relationships, whilst weak arguments – whether due to weak premises or to weak relationships – tend to use logical fallacies to appear stronger than they are or to appear to weaken an opposing argument. Most people inadvertently commit logical fallacies in presenting an argument, but regrettably they are often deliberately used by politicians, the media, salespeople, and others to manipulate and fool people, and by those in power and authority to deflect, denigrate, or dismiss criticism.
It is important to recognize these fallacies so that one can avoid letting a debate be hijacked and insist that it return to the actual issue under discussion.
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Where two alternative states are presented as the only or exclusive possibilities, when in fact more possibilities exist, both possibilities may co-exist, and/or neither may be valid.» more »
Casting the argument in the mold of a hero-villain story.» more »
Misrepresenting someone’s argument to make it easier to attack.» more »
Reduction to Absurdity
Reductio ab Absurdum or Argumentum ab Absurdum.» more »
Asserting that if we allow A to happen, then Z will consequently happen too, therefore A should not happen.» more »
Changing the Subject
Avoiding engagement with an argument by creating a new one.» more »
Excluding the Middle, leaping from a premise to conclusion without a valid intervening connection.
Attacking your opponent’s character or personal traits, or simply name calling, in an attempt to thereby undermine or dismiss their argument.» more »
Judging something good or bad on the basis of where or whom it comes from.» more »
Appealing to popularity or the fact that many people do or believe something as an attempted form of validation.» more »
Appeal to Emotion
Manipulating an emotional response in place of a valid or compelling argument.
Also: Argumentum ad Populum, appealing to group fears and prejudices, myths and ideals.» more »
Appeal to Authority
Saying that because an authority says something, it must therefore be true.» more »
Appeal to Nature
Making the argument that because something is ‘natural’ it is therefore valid, justified, inevitable, good, or ideal.» more »
Moving the goalposts, or asserting exception or new conditions when a claim is shown to be false.
No True Scotsman
Making an Appeal to Purity as a way to dismiss relevant criticisms or flaws of an argument.» more »
Avoiding having to engage with criticism by turning it back on the accuser – answering criticism with criticism.» more »
Assuming someone or something has the same characteristics as you and yours.» more »
Begging the Question
A circular argument, in which the conclusion is included in the premise.» more »
Asking a question that has an assumption built into it so that it can’t be answered without appearing guilty.» more »
Dismissing a claim by accusing the person making it of being manipulated by or suggestible to the agendas of others.» more »
Ignoring, dismissing, or wrongly interpreting, explaining, and recalling evidence to confirm or protect one’s beliefs and prejudices.» more »
Presuming that a real or perceived relationship between things means that one is the cause of the other.» more »
Cherry-picking data clusters to suit an argument, or finding a pattern to fit a presumption.» more »
Burden of Proof
Saying that the burden of proof lies not with the person making the claim, but with someone else to disprove the claim.» more »
Using personal experience or an isolated example instead of a valid argument, especially to dismiss statistics.» more »
Assuming that what’s true about one thing or a part of something is true about something similar or the whole.» more »
Saying that because one finds something difficult to understand, it’s therefore not true.» more »
Using double meanings, ambiguities of language, or equivocation, which weakens the conclusions or defies being pinned down.» more »
Asserting that two conflicting ideas are the same.» more »
Saying that a compromise, or middle point, between two extremes must be the truth.» more »
Believing that ‘runs’ occur (or don’t occur) to statistically independent phenomena such as roulette wheel spins.» more »
Presuming a claim to be necessarily wrong because a fallacy has been committed in its the argument.» more »
[originally adapted from yourlogicalfallacyis.com]