A logical fallacy is a error in reasoning due to a misconception or presumption, which makes the argument invalid. If, for example, the assumptions of an argument are true, the argument can still be rendered invalid if the logic used to achieve the conclusion are not valid. That is, if the logic is “fallacious”. A collection of bad arguments are called “logical fallacies”.
Our brains tend to take shortcuts when solving problems – called “heuristics”. These rules of thumb are handy, and are true some of the time, but they can also lead to cognitive errors when they are substituted for formal logic.
People can easily and unintentionally fall victim to logical fallacies, but can also use them purposefully to seemingly win an argument against another person who doesn’t understand them. Here’s 24 logical fallacies you should understand and avoid using. If you’re super keen, you can print and cut them out as flash cards, which will most certainly make you the coolest person at the party.
A version in text format is below the infographic.
Logical Fallacies You Should Learn and Avoid
- STRAWMAN: Misrepresenting someone’s argument to make it easier to attack.
- SLIPPERY SLOPE: You said that if we allow A to happen, then Z will eventually happen too, therefore A should not happen.
- SPECIAL PLEADING: You moved the goalposts or made up an exception when your claim was shown to be false.
- THE GAMBLER’S FALLACY: You said that ‘runs’ occur (like getting 7 red numbers in a row at a roulette table), not realizing that each spin (event) is completely independent.
- BLACK-OR-WHITE (AKA FALSE DICHOTOMY): You presented two alternative states as the only possibilities, when in fact more possibilities exist (the “grey area”)
- FALSE CAUSE (AKA Post Hoc, Ergo Propter Hoc (Literally: “After this, therefore because of this”): You presumed that a real or perceived relationship between things means that one is the cause of the other.
- AD HOMINEM: You attacked your opponent’s character or personal traits in an attempt to undermine their argument. Politicians do this frequently (among many logical fallacies, of course).
- LOADED QUESTION: You asked a question that had a presumption built into it so that it couldn’t be answered without appearing guilty.
- BANDWAGON: You appealed to popularity or the fact that many people do something as an attempted form of validation.
- BEGGING THE QUESTION: You presented a circular argument in which the conclusion was included in the premise. (Example: The Bible is true because God exists, and God exists because the Bible says so, therefore the Bible is true since God exists…)
- APPEAL TO AUTHORITY: You said that because an authority thinks something, therefore it must be true.
- APPEAL TO NATURE: You argued that because something isn’t ‘natural’ it is therefore valid, justified, inevitable, good, or ideal.
- COMPOSITION/DIVISION: You assumed that one part of something has to be applied to all, or other, parts of it; or that the whole must apply to its parts.
- ANECDOTAL: You used a personal experience or an isolated example instead of a sound argument or compelling evidence.
- APPEAL TO EMOTION: You attempted to manipulate an emotional response in place of valid or compelling argument.
- TU QUOQUE: You avoided having to engage with criticism by turning it back on the accuser. You answered criticism with criticism.
- BURDEN OF PROOF: You said that the burden of proof lies not with the person making the claim, but with someone else to disprove. Extraordinary claims require extraordinary evidence.
- NO TRUE SCOTSMAN: You made what could be called an appeal to purity as a way to dismiss relevant criticisms or flows of your argument.
- TEXAS SHARPSHOOTER: You cherry-picked a data cluster to suit your argument. or found a pattern to fit a presumption. (Example: Climate change deniers zooming in on a small part of the graph and ignoring the trend in the entire data set.)
- FALLACY FALLACY: You presumed that because a claim has been poorly argued, or a fallacy has been made, that the claim itself must be wrong.
- PERSONAL INCREDULITY: Because you found something difficult to understand, or are unaware how it works, you made out like it’s probably not true. (Example: Bill O’Reilly doesn’t understand how the tides work… therefore God did it.)
- AMBIGUITY: You used a double meaning or ambiguity of language to mislead or misrepresent the truth.
- GENETIC: You judged something as either good or bad on the basis of where it comes from, or from whom it came.
- MIDDLE GROUND: You claimed that a compromise, or middle point, between two extremes must be the truth.