The following common informal logical fallacies are verbatim from an article published by The Best Schools. I highly recommend checking out their website if you’re looking to attend college or university in America and need a bit of guidance or further research. This article is part one, click here to read part two.

What is a Logical Fallacy?

A logical fallacy is an error in reasoning common enough to warrant a fancy name. Knowing how to spot and identify fallacies is a priceless skill. It can save you time, money, and personal dignity. There are two major categories of logical fallacies, which in turn break down into a wide range of types of fallacies, each with their own unique ways of trying to trick you into agreement.

Ad Hominem Fallacy

Ad hominem is an insult used as if it were an argument or evidence in support of a conclusion.

When people think of “arguments,” often their first thought is of shouting matches riddled with personal attacks. Ironically, personal attacks run contrary to rational arguments. In logic and rhetoric, a personal attack is called an ad hominem. Ad hominem is Latin for “against the man.” Instead of advancing good sound reasoning, an ad hominem replaces logical argumentation with attack-language unrelated to the truth of the matter.

More specifically, the ad hominem is a fallacy of relevance where someone rejects or criticizes another person’s view on the basis of personal characteristics, background, physical appearance, or other features irrelevant to the argument at issue.

An ad hominem is more than just an insult. It’s an insult used as if it were an argument or evidence in support of a conclusion. Verbally attacking people proves nothing about the truth or falsity of their claims. Use of an ad hominem is commonly known in politics as “mudslinging.” Instead of addressing the candidate’s stance on the issues, or addressing his or her effectiveness as a statesman or stateswoman, an ad hominem focuses on personality issues, speech patterns, wardrobe, style, and other things that affect popularity but have no bearing on their competence. In this way, an ad hominem can be unethical, seeking to manipulate voters by appealing to irrelevant foibles and name-calling instead of addressing core issues. In this last election cycle, personal attacks were volleyed freely from all sides of the political aisle, with both Clinton and Trump facing their fair share of ad hominem fallacies.

Strawman Argument

With the strawman argument, someone attacks a position the opponent doesn’t really hold.

It’s much easier to defeat your opponent’s argument when it’s made of straw. The Strawman argument is aptly named after a harmless, lifeless, scarecrow. In the strawman argument, someone attacks a position the opponent doesn’t really hold. Instead of contending with the actual argument, he or she attacks the equivalent of a lifeless bundle of straw, an easily defeated effigy, which the opponent never intended upon defending anyway.

The strawman argument is a cheap and easy way to make one’s position look stronger than it is. Using this fallacy, opposing views are characterized as “non-starters,” lifeless, truthless, and wholly unreliable. By comparison, one’s own position will look better for it. You can imagine how strawman arguments and ad hominem fallacies can occur together, demonizing opponents and discrediting their views.

Appeal to Ignorance (argumentum ad ignorantiam)

An appeal to ignorance isn’t proof of anything except that you don’t know something.

Any time ignorance is used as a major premise in support of an argument, it’s liable to be a fallacious appeal to ignorance. Naturally, we are all ignorant of many things, but it is cheap and manipulative to allow this unfortunate aspect of the human condition to do most of our heavy lifting in an argument. Interestingly, appeal to ignorance is often used to bolster multiple contradictory conclusions at once.

False Dilemma/False Dichotomy

Dilemma-based arguments are only fallacious when, in fact, there are more than the stated options.

This fallacy has a few other names: “black-and-white fallacy,” “either-or fallacy,” “false dichotomy,” and “bifurcation fallacy.” This line of reasoning fails by limiting the options to two when there are in fact more options to choose from. Sometimes the choices are between one thing, the other thing, or both things together (they don’t exclude each other). Sometimes there is a whole range of options, three, four, five, or a hundred and forty-five. However it may happen, the false dichotomy fallacy errs by oversimplifying the range of options.

Dilemma-based arguments are only fallacious when, in fact, there are more than the stated options. It’s not a fallacy however if there really are only two options. For example, “either Led Zeppelin is the greatest band of all time, or they are not.” That’s a true dilemma, since there really are only two options there: A or non-A. It would be fallacious however to say, “There are only two kinds of people in the world: people who love Led Zeppelin, and people who hate music.” Some people are indifferent about that music. Some sort of like it, or sort of dislike it, but don’t have strong feelings either way.

The false dilemma fallacy is often a manipulative tool designed to polarize the audience, heroicizing one side and demonizing the other. It’s common in political discourse as a way of strong-arming the public into supporting controversial legislation or policies.

Slippery Slope Fallacy

The slippery slope fallacy suggests that unlikely or ridiculous outcomes are likely when there’s just not enough evidence to think so.

You may have used this fallacy on your parents as a teenager: “But, you have to let me go to the party! If I don’t go to the party, I’ll be a loser with no friends. Next thing you know I’ll end up alone and jobless living in your basement when I’m 30!” The slippery slope fallacy works by moving from a seemingly benign premise or starting point and working through a number of small steps to an improbable extreme.

This fallacy is not just a long series of causes. Some causal chains are perfectly reasonable. There could be a complicated series of causes that are all related, and we have good reason for expecting the first cause to generate the last outcome. The slippery slope fallacy, however, suggests that unlikely or ridiculous outcomes are likely when there is just not enough evidence to think so.

It’s hard enough to prove one thing is happening or has happened; it’s even harder to prove a whole series of events will happen. That’s a claim about the future, and we haven’t arrived there yet. We, generally, don’t know the future with that kind of certainty. The slippery slope fallacy slides right over that difficulty by assuming that chain of future events without really proving their likelihood.

Circular Argument (petitio principii)

When a person’s argument is just repeating what they already assumed beforehand, it’s not arriving at any new conclusion. We call this a circular argument or circular reasoning. If someone says, “The Bible is true; it says so in the Bible”—that’s a circular argument. They are assuming that the Bible only speaks truth, and so they trust it to truthfully report that it speaks the truth, because it says that it does. It is a claim using its own conclusion as its premise, and vice versa, in the form of “If A is true because B is true; B is true because A is true”. Another example of circular reasoning is, “According to my brain, my brain is reliable.” Well, yes, of course we would think our brains are in fact reliable if our brains are the one’s telling us that our brains are reliable.

Circular arguments are also called Petitio principii, meaning “Assuming the initial [thing]” (commonly mistranslated as “begging the question”). This fallacy is a kind of presumptuous argument where it only appears to be an argument. It’s really just restating one’s assumptions in a way that looks like an argument. You can recognize a circular argument when the conclusion also appears as one of the premises in the argument.

Hasty Generalization

Hasty generalization may be the most common logical fallacy because there’s no single agreed-upon measure for “sufficient” evidence.

A hasty generalization is a general statement without sufficient evidence to support it. A hasty generalization is made out of a rush to have a conclusion, leading the arguer to commit some sort of illicit assumption, stereotyping, unwarranted conclusion, overstatement, or exaggeration.

Normally we generalize without any problem; it is a necessary, regular part of language. We make general statements all the time: “I like going to the park,” “Democrats disagree with Republicans,” “It’s faster to drive to work than to walk,” or “Everyone mourned the loss of Harambe, the Gorilla.”

Indeed, the above phrase “all the time” is a generalization — we aren’t literally making these statements all the time. We take breaks to do other things like eat, sleep, and inhale. These general statements aren’t addressing every case every time. They are speaking generally, and, generally speaking, they are true. Sometimes you don’t enjoy going to the park. Sometimes Democrats and Republicans agree. Sometimes driving to work can be slower than walking if the roads are all shut down for a Harambe procession.

Hasty generalization may be the most common logical fallacy because there’s no single agreed-upon measure for “sufficient” evidence. Is one example enough to prove the claim that, “Apple computers are the most expensive computer brand?” What about 12 examples? What about if 37 out of 50 apple computers were more expensive than comparable models from other brands?

There’s no set rule for what constitutes “enough” evidence. In this case, it might be possible to find reasonable comparison and prove that claim is true or false. But in other cases, there’s no clear way to support the claim without resorting to guesswork. The means of measuring evidence can change according to the kind of claim you are making, whether it’s in philosophy, or in the sciences, or in a political debate, or in discussing house rules for using the kitchen. A much safer claim is that “Apple computers are more expensive than many other computer brands.”

Meanwhile, we do well to avoid treating general statements like they are anything more than simple, standard generalizations, instead of true across the board. Even if it is true that many Apple computers are more expensive than other computers, there are plenty of cases in which Apple computers are more affordable than other computers. This is implied in the above generalization, but glossed over in the first hasty generalization.

A simple way to avoid hasty generalizations is to add qualifiers like “sometimes,” “maybe,” “often,” or “it seems to be the case that . . . “. When we don’t guard against hasty generalization, we risk stereotyping, sexism, racism, or simple incorrectness. But with the right qualifiers, we can often make a hasty generalization into a responsible and credible claim.

The above is verbatim from an article published by The Best Schools. I highly recommend checking out their website if you’re looking to attend college or university in America and need a bit of guidance or further research. This article is part one, click here to read part two.

I’d love to know…

What fallacy do you most commonly experience in debate?

How many of these fallacies have you encountered?

What fallacy are you guilty of using?