Fallacies are errors in logic and/or reasoning. You should avoid the use of fallacies in your arguments because they detract from your credibility and the legitimacy of your message. However, without prior knowledge of fallacious arguments and careful attention to the details of your argument, you may find yourself accidentally using fallacies. Below, you will find a list and description of popular fallacies. Use this information to avoid the use of fallacious arguments while crafting your next presentation. Once you finish forming your arguments, use this as a checklist to ensure your arguments are logical and reasonable.

Ad Hominem: Latin for "against the person," an ad hominem fallacy happens when a person, not his or her ideas and/or positions, are attacked. Also known as "name calling," this fallacy seems like it may only happen in elementary schools. Unfortunately, we see it on cable news shows and in our government far too often. If you disagree with someone, be sure to understand and articulate why.

Video Explanation

Appeal to Misplaced Authority: Have you ever wondered why advertisers use celebrities in commercials? It's no secret that popular figures attract more consumers than those whose names we do not know. Justin Bieber for Proactive and Katy Perry for Adidas are just two of many examples of what might be appeals to misplaced authority. Sure, we know who these two people are, but should we base our buying habits on their endorsements? How much does Bieber know about facial cleansers and chemistry? How much does Katy know about athletic gear and fabric manufacturing? For a presentation, be sure to use credible sources. Remember, even though it may look or sound good, don't use it in your argument unless it is reliable, objective, and accurate.

Bandwagon: You may have heard the expression, "jumping on the bandwagon" associated with sports teams. As soon as a team has a good season, many new fans "jump on the bandwagon" and suddenly support the team for the first time.

Either-or: "Do you like chocolate or vanilla ice cream? What do you mean you like strawberry? You have to either like chocolate or vanilla!" This is an example of an either-or fallacy. Often, people present issues as though there are only two possible positions. In reality, there are multiple positions that can be taken on most issues. Don't ignore the middle ground. After all, that's where most of your audience is likely to be found.

False Cause: Why did you fail the test? Why did you make an A? It seems easy to answer these questions with, "the teacher doesn't like me," or "because I'm smart." However, these answers may not accurately explain the cause of your academic outcome. If you claim that one event caused another event to happen, but sure to establish a clear and causal connection. Remember to examine the causal links thoroughly because cause-effect relationships are more complicated than they seem.

Hasty Generalization: Each person has unique life experiences. These various experiences make us individuals-none just like another. However, some people make unfair assumptions about groups of individuals based on a unique experience. For example, if a significant other cheated on you, it may be tempting to assume that all future significant others will do the same. A hasty generalization happens when you use limited, personal experiences to make larger assumptions about groups of people. While large, numeric research allow some generalizations to be made, avoid generalizing from limited knowledge or experience.

Red Herring: Have you ever had an argument with a friend or family member? Just as you were making your point, they may have reminded you about something stupid you did two years ago. The new information has nothing to do with the argument at hand, but it likely interrupted your thought process. If this has ever happened to you, you have been a victim of a red herring fallacy. Red herrings happen when irrelevant information is used to distract someone from the issue at hand. Be sure to stay on track and focus on relevant information when creating arguments.

Slippery Slope: Imagine standing atop an ice covered hill. If your footing slips on your first step down, you risk falling uncontrollably to a hard landing at the bottom. This physical situation is a representation of how slippery slop fallacies work. Gay marriage leading to the downfall of America, or marijuana legalization resulting in a nation of drug addicts are both examples of slippery slope fallacies. It's true that each action has a reaction, but beware of making extreme claims.

This is not a complete list of fallacies that you are likely to find, and possibly use, in arguments. In fact, more complete lists include well over 100 hundred types of fallacies. Remember to examine your own arguments using both logic and common sense. If something seems like it is not right, it may need to be revised. If you are unsure if your argument includes fallacies, make an appointment at the GV Speech Lab today. We will be happy to listen to your arguments and collaborate with you on strengthening them.

Prepared by Carl J. Brown

Information partially adapted from Stephen Lucas' The Art of Public Speaking, Tenth Edition; Beebe, Beebe, & Ivy's Communication Principles for a Lifetime, Fourth Edition