People knowingly and unknowingly engage in bad reasoning—especially in meetings and arguments. Using bad logic and fallacious reasoning, one can easily create a strong case that looks accurate and unbeatable, when in fact, it’s just a trick i.e., the logic of the argument is fallacious.
A precursor to effective persuasion is taking down your opponent’s logic by finding flaws in their claims while also dodging their attacks. Here’s a list of 25 most common logical fallacies that would help you arm yourself against false arguments disguised to look good.
Ad Hominem
Attacking the person making the argument, rather than the argument itself, when the attack on the person is completely irrelevant to the argument the person is making. This is one of the most common forms of attack to invalidate a person’s claim. For example, a parent says that a teacher doesn’t know how to teach because she didn’t go to a prestigious college.
There are other variations of Ad Hominem such as, suggesting that the person who is making the argument is biased, or predisposed to take a particular stance, and therefore, the argument is necessarily invalid. For example, a VC arguing for the Silicon Valley business model of growing big by losing money.
Or, a person is viewed negatively because of their association with another person or group that is already viewed negatively. For example, when you supported equal pay for equal work, you were associated with some extremist feminist group and therefore dismissed.
Strawman Fallacy
Substituting a person’s actual position or argument with a distorted, exaggerated, or misinterpreted version of the position of the argument. For example, when you ask your friends not to bully the new kid, they accuse you of choosing the new kid’s side instead of your friends.
Red Herring
Attempting to redirect the argument to another issue that to which the person doing the redirecting can better respond. Red Herring is a deliberate diversion of attention with the intention of trying to abandon the original argument. For example, when your wife asks why have you forgotten to pay the bills, you start talking about this amazing restaurant that you both just gotta go.
Slippery Slope
This is an absurd extrapolation when a relatively insignificant first event is suggested to lead to a more significant event, which in turn leads to a more significant event, and so on, until some ultimate, significant event is reached, where the connection of each event is not only unwarranted, but with each step it becomes more and more improbable.
For example, If we don’t lock children in the closet, they would want to roam in the house. If we allow that, they’ll start roaming in the neighbourhood. They next thing you know, they’ll get into accidents, or god forbid, get kidnapped and then sold as a slave in some country. Therefore, it’s better if we lock them up in closets. It’s for their own good.
Loaded Question
A question that has a presupposition built in, which implies something but protects the one asking the question from accusations of false claims. It is a form of misleading discourse, and it is a fallacy when the audience does not detect the assumed information implicit in the question, and accepts it as a fact. For example, “How many times a week do you beat your children?” already established that you do beat up your children.
Circular Reasoning
A type of reasoning in which the proposition is supported by the premises, which is supported by the proposition, creating a circle in reasoning where no useful information is being shared.
Circular reasoning may sound humorous, but it can be very convincing to those who already accept the argument as true, and are more likely to be further convinced. For example, “The Bible if the word of God. Because God tells us it is… in the Bible.”
False Dilemma
When only two choices are presented yet more exist, or a spectrum of possible choices exist between two extremes. False dilemmas are usually characterised by “either this or that” language, but can also be characterised by omissions of choices. For example, “It’s either this or war,” or, “If you aren’t with us, you are against us.” Another variety is the false trilemma, which is when three choices are presented when more exist. For example when you say, “That guy is insolent, dumb, and a liar,” but you miss out that he is also very popular.
Appeal to Common Belief
When the claim that most or many people in general or of a particular group accept a belief as true is presented as evidence for the claim. This is when people give in to bias by social proof. Just because a lot of people are against something, it’s automatically perceived as bad.
Accepting another person’s belief, or many people’s beliefs, without demanding evidence as to why that person accepts the belief, is lazy thinking and a dangerous way to accept information. Remember: if 50 Mn people say something foolish, it is still foolish.
Appeal to Emotion
This is the general category of many fallacies that use emotion in place of reason in order to attempt to win the argument. It is a type of manipulation used in place of valid logic. Appeal to Common Belief an example. Other popular examples are, Appeal to Extremes, Appeal to Faith, Appeal to Flattery, Appeal to Authority, etc.
Anonymous Authority
When an unspecified source is used as evidence for the claim. This is commonly indicated by phrases such as “They say that…”, “It has been said…”, “I heard that…”, “Studies show…”, or generalised groups such as, “Scientists say…” When we fail to specify a source of the authority, we can’t verify the source, thus the credibility of the argument.
Appeals to anonymous sources are more often than not, either a way to fabricate, exaggerate, or misrepresent “facts” in order to deceive others into accepting a claim.
Argument from Ignorance
The assumption of a conclusion or fact based primarily on lack of evidence to the contrary. Usually best described by, “Absence of evidence is not evidence of absence.” For example, when you say that you have no evidence that closing malls, theatres, and schools would prevent the spread of a virus, there’s absence of evidence, not evidence of absence.
Argument by Repetition
Repeating an argument or a premise over and over again in place of more supporting evidence. “It’s true. This person should be nominated. If any person, it should be him, and nobody else. Others maybe deserving, but not as deserving as this guy. It’s true!” Here no evidence has been presented. The same thing has been mentioned over and over again to make it sound plausible. Politicians often raise their voice to stir emotions and make it more effective.
Hasty Generalisation
Drawing a conclusion based on a small sample size (usually one anecdote), rather than looking at statistics that are much more in line with the typical or average situation. For example, since I know a person who smoked 4 packets everyday and still lived till 94, I can safely conclude that cigarette smoking isn’t injurious to health.
Poisoning the Well
To commit a pre-emptive Ad Hominem attack against an opponent. That is, to prime the audience with adverse information about the opponent from the start, in an attempt to make your claim more acceptable, or discount the credibility of your opponent’s claim. For example, my opponent who is about to present his case has donated millions to oil companies. He supports drilling for oil in protected locations. Mind you, he’s a wolf in sheep’s clothing.
No True Scotsman
When a universal (“all”, “every”, etc.) claim is refuted, rather than conceding the point or meaningfully revising the claim, the claim is altered by going from universal to specific, and failing to give any objective criteria for the specificity. The No True Scotsman fallacy appeals to the “purity” of an ideal or standard as a way to dismiss relevant criticisms or flaws in your argument. For example, all those who follow me will live happily ever after. Okay, then why are so many unhappy among the followers? Well, they aren’t really true followers.
False Cause
Concluding that one thing caused another, simply because they are regularly associated. For example, many homosexuals have AIDS, therefore, homosexuality causes AIDS.
Special Pleading
Applying standards, principles, and/or rules to other people or circumstances, while making oneself or certain circumstances exempt from the same critical criteria, without providing adequate justification. Special pleading is often a result of strong emotional beliefs that interfere with reason. For example, drunk drivers should be punished, but he is only a kid, who’s good at heart. This was his only mistake. Please let him go!
Weak Analogy
When an analogy is used to prove or disprove an argument, but the analogy is too dissimilar to be effective, that is, it is unlike the argument more than it is like the argument. For example, not believing that ghosts exit just because you didn’t see one is like saying that your great grandfather didn’t exist just because you yourself didn’t see him.
Stereotyping
The general beliefs that we use to categorise people, objects, and events, while assuming those beliefs are accurate generalisations of the whole group. For example, all rich people are evil. Let’s ban the billionaires.
Style Over Substance
When the arguer embellishes the argument with compelling language or rhetoric, and/or visual aesthetics. If it sounds or looks good, it must be right. For example, a chain is only as strong as its weakest link. It works wonders if it rhymes, for example, whomever smelled it, dealt it! Proverbs, such as, “Tit for tat,” also do the trick.
Unfalsifiability
Confidently asserting that a theory or hypothesis is true or false even though the theory or hypothesis cannot possibly be contradicted by an observation or the outcome of any physical experiment, usually without strong evidence or good reasons.
Making unfalsifiable claims are a way to leave the realm of rational discourse, since unfalsifiable claims are usually not founded on evidence and reason. For example, you are depressed as an adult because of mental trauma you suffered as a kid. But there’s no scientific method to either prove or disprove it.
Tu Quoque
Claiming that an argument is flawed by pointing out the hypocrisy in the opponent—that the one making the argument is not acting consistently with the claims of the argument. This tactic doesn’t solve the problem, or prove one’s point, because even hypocrites can tell the truth. For example, vegans talking about the benefits of having milk are frowned upon for not following their own advice. However, it doesn’t make their argument any wrong.
Equivocation
Equivocation happens when a word, phrase, or sentence is used deliberately to confuse, deceive, or mislead by sounding like it’s saying one thing but actually saying something else. Equivocation comes from the roots “equal” and “voice” and refers to two-voices; a single word can “say” two different things. Another word for this is ambiguity. For example, when a politician says that his party is planning a strategic federal investment in critical programs with the taxpayer’s money.
Shoehorning
The process of force-fitting some current affair into one’s personal, political, or religious agenda. Many people aren’t aware of how easy it is to make something look like confirmation of a claim after the fact, especially if the source of the confirmation is something in which they already believe. Shoehorned claims, for example, a certain startup is successful because of having a female CEO, are unfalsifiable.
Rationalisation
Offering false or made-up excuses for our claim because we know the real reasons are much less persuasive to share.