Logical Fallacies

Logical fallacies are errors in reasoning that are based on poor or faulty logic. When presented in a formal argument, they can cause you to lose your credibility as a writer, so you have to be careful of them.

Sometimes, writers will purposefully use logical fallacies to make an argument seem more persuasive or valid than it really is. In fact, the examples of fallacies on the following pages might be examples you have heard or read. While using fallacies might work in some situations, it’s irresponsible as a writer, and, chances are, an academic audience will recognize the fallacy.

However, most of the time, students accidentally use logical fallacies in their arguments, so being aware of logical fallacies and understanding what they are can help you avoid them. Plus, being aware of these fallacies can help you recognize them when you are reading and looking for source material. You wouldn’t want to use a source as evidence if the author included some faulty logic.

Last semester, several students worked together to create activities to help their peers understand Logical Fallacy.   Now, you can benefit from their work.   While there may be errors, these activities are a great way to learn some of the logical fallacies.

There are approximately 145 different logical fallacies.  No, you don’t need to know them all!  We are going to look at some of the most common logical fallacies in this chapter.  Let’s start with a brief interactive page that shows the definitions of different logical fallacies.

Follow this link to see “Your Logical Fallacy”.

If you hover over the images, it will tell you the definition. If you click on it, they will give deeper explanations and examples.

Several students created projects to help you define logical fallacies.  Take a look at these lovely examples.

The comic below gives you a little insight into what this fallacy might look like. Observe as Captain Logic saves the day from faulty logic and the evil Dr. Fallacy!

In this comic, you’ll notice that Dr. Fallacy is presenting only two options, but the first person clearly has a middle position. You have to be really careful of this kind of fallacy, as it can really turn your audience away from your position. The world is complex, and the way people think is complex. If you dismiss that, you could lose the respect and interest of your audience.

Hasty Generalization Fallacy

The hasty generalization fallacy is sometimes called the over-generalization fallacy. It is basically making a claim based on evidence that it just too small. Essentially, you can’t make a claim and say that something is true if you have only an example or two as evidence.

You can see Dr. Fallacy in action with this type of fallacy in the comic below.

In this example, Dr. Fallacy is making a claim that all teenagers are bad based on the evidence of one incident. Even with the evidence of ten incidences, Dr. Fallacy couldn’t make the claim that all teenagers are problems.

In this instance, the fallacy seems clear, but this kind of fallacious thinking is quite common. People will make claims about all kinds of things based on one or two pieces of evidence, which is not only wrong but can be dangerous. It’s really easy to fall into this kind of thinking, but we must work to avoid it. We must hold ourselves to higher standards when we are making arguments.

Appeal to Fear Fallacy

This type of fallacy is one that, as noted in its name, plays upon people’s fear. In particular, this fallacy presents a scary future if a certain decision is made today.

You can see this fallacy in action in Dr. Fallacy’s campaign ad in the comic below.

Thankfully, the voters saw through Dr. Fallacy’s faulty logic. While this kind of claim seems outlandish, similar claims have been made by candidates in elections for years. Obviously, this kind of claim isn’t logical, however. No one can predict the future, but making a bold claim like this with no evidence at all is a clear logical fallacy.

Ad Hominem Fallacy

Ad hominem means “against the man,” and this type of fallacy is sometimes called name-calling or the personal-attack fallacy. This type of fallacy occurs when someone attacks the person instead of attacking his or her argument.

Check out Dr. Fallacy as he tries to get away with this type of fallacy. Thankfully, Captain Logic OWL saves the day!

In this example, Dr. Fallacy doesn’t address the issue of minimum wage and, instead, attacks the person. When we attack the person instead of tackling the issue, our audience might think we don’t understand the issue or can’t disprove our opponent’s view. It’s better to stick to the issue at hand and avoid ad hominem fallacies.

Slippery Slope Fallacy

A slippery slope fallacy occurs when someone makes a claim about a series of events that would lead to one major event, usually a bad event. In this fallacy, a person makes a claim that one event leads to another event and so on until we come to some awful conclusion. Along the way, each step or event in the faulty logic becomes more and more improbable.

See Dr. Fallacy in the comic below try to get away with this fallacy. Fortunately, Captain Logic saves logic and saves the day!

In this example, Dr. Fallacy is following a slippery slope to get to the point that any kind of gun regulation will lead to terrorists taking over the country. The series of events is extremely improbable, and we simply can’t make claims like this and be taken seriously in our arguments.

Of course, this example is extreme, but we do need to make sure if we are creating a line of reasoning in terms of events leading to other events, that we aren’t falling into a slippery slope fallacy.

Bandwagon Fallacy

The bandwagon fallacy is also sometimes called the appeal to common belief or appeal to the masses because it’s all about getting people to do or think something because “everyone else is doing it” or “everything else thinks this.”

In the comic below, Dr. Fallacy tries to persuade people using this type of fallacy.

Of course, the problem with this fallacy is not everyone is actually doing this, but there is another problem that’s important to point out. Just because a lot of people think something or do something does not mean it’s right or good to do. For example, in the 16^th century, most people believed the earth was the center of the universe; of course, believing that did not make it true.

You want to be careful to avoid this fallacy, as it’s easy to fall into this kind of thinking. Think about what your parents asked you when you insisted that “everyone” was doing something that you were not getting to do: “If every one of your friends jumped off of a cliff, would you?” It’s important to fight the urge to fall into a bandwagon fallacy.

Guilt by Association Fallacy

A guilt by association fallacy occurs when someone connects an opponent to a demonized group of people or to a bad person in order to discredit his or her argument. The idea is that the person is “guilty” by simply being similar to this “bad” group and, therefore, should not be listened to about anything.

See Dr. Fallacy use this fallacy by associating his opponent with someone named Dr. Crazy. Clearly, this person isn’t someone to be associated with. Thankfully, Captain Logic OWL points out this flawed logic to the school board.

Here, we don’t see what issues Dr. Fallacy has with the educational reform plan, as this isn’t addressed in the fallacy. Instead of dealing with the issue, this person tries to just dismiss the point by connecting his or her opponent’s ideas with the ideas of a person who the audience wouldn’t believe.

This is problematic, of course, because we don’t deal with the issue at hand. Plus, just because “Dr. Crazy” thinks the same thing or something similar doesn’t mean we should automatically dismiss it. We need to look more closely at the issue at hand, and it seems like the person using this fallacy doesn’t want us to.

Since Dr. Fallacy is once again thwarted by Captain Logic, this may, indeed, be his last fallacy, at least for now…

Putting It All Together

After completing this activity, you may download or print a completion report that summarizes your results.

Analyze This

Fallacies are everywhere! You have learned about some of the most common logical fallacies but now it’s time to see some examples of how we encounter these fallacies in our everyday lives.

In the video below, a student examines some ads for fallacies. Watch and listen as he identifies fallacies that we should be aware of.

See It in Practice

The key thing to remember with logical fallacies is that we want to avoid faulty logic in our writing and we want to be aware of faulty logic in the source material we find. Even if you can’t remember the different types of fallacies, as long as you are aware of logical fallacies and work to avoid any kind of faulty logic, you’re going to be in good shape as you develop arguments.

In this video, watch as our student revises her essay to make sure she has avoided logical fallacies in her arguments.

Fallacy Quick Reference Chart

The following is a fairly comprehensive table of fallacies, and its purpose is for you to use a reference to ensure that you do not create a logical fallacy as you are writing about your discoveries throughout your rhetorical analysis.

Your Turn

It’s your turn now to make sure you are aware of fallacies and have worked to avoid them in your writing and in the sources you use in your essay. It’s a good idea to review the fallacy activities to have them fresh in your mind as you revise for logic in your argument.

This is also a good time to get outside feedback and support. It can be especially difficult to identify faulty logic in our own writing, especially if we feel emotionally connected to our content. Have your professor, a classmate, or a friend or family member review your essay with an eye toward the logic in your arguments.

ATTRIBUTIONS

• Content Adapted from Excelsior Online Writing Lab (OWL). (2020).  Excelsior College. Retrieved from https://owl.excelsior.edu/ licensed under a Creative Commons Attribution-4.0 International License.