When engaging in a debate, topical argument or even a friendly discussion, one side may often accuse the other of a lie, untruth or error of fact. While this may be the case, it might just be a fallacy, which appears to be true but instinctually the person knows it is not.

A fallacy is an error in logic rather than truth. Most fallacies can be broken down to an algebraic syllogism. Fallacies have been studied by many people, especially for the development of critical thinking. There are over forty named fallacies, most with Latin names as well as the English. It should be remembered that in some circumstances, a fallacy-based method of reasoning may in fact reach a true conclusion. There is even an Internet site which lists famous quotes which contain fallacies.

Lawyers use fallacies to push witnesses and juries to the wrong conclusion (and hopefully the opposition objects). Lawyers also use fallacies to persuade a person or company in a particular direction. They don’t always define the fallacy, even to themselves, but rather know what to say to change or create a point of view. It is up to the client to see through such “logic”.

A second common source for fallacies is advertising, again in an effort to persuade citizens to purchase their products. For instance, (and these are fictitious), Brushalot might claim that 3 out of 4 dentists recommend their toothpaste, while Dropatooth claims that 80% of dentists recommend their brand. Obviously, both claims cannot be true. But if one listens carefully, there may be a caveat such as “of dentists polled”. Another example is when a cosmetic or over-the-counter drug advertises that there were clinical trials. Unfortunately, if investigated,  it often turns out that there was only one clinical trial – of three people.

Perhaps the biggest faulty citation is from the Internet. People will state that they know something is right or real because they read it on the Internet. Since there is no way to regulate the Internet, such sources are more often than not biased, if not completely untrue. Newspapers are under the same scrutiny, but tend to be more careful to check the facts, and are better regulated. Unless they are tabloids.

Some of the more common fallacies can be grouped by the type of logic error involved. The ad Hominem (against a person) set covers arguments against the person making the statement. The most common one is to denigrate the speaker – “You can’t judge a beautiful painting because you are ugly”; “You can’t speak on politics since you are not a lawyer” ; “A Christian should not comment on Jewish folklore”. Also in this category is the you-too fallacy, where the speaker’s statement is dismissed because it is inconsistent with the speaker’s previous statements or actions. For instance, claiming that a convicted murderer cannot voice an opinion against homicide, or even an athlete who was drummed out of the corps for drug use becoming a sports commentator.. A circumstantial ad Hominem is when the speaker’s claim is dismissed because the claim in in one’s self-interest. To tell someone he should give you his 1965 Mustang because you, as a younger, unmarried person who would look better in it and make better use of it, would be a fallacy. To suggest that he sell it to you for a fair price, for the same reasons, would not be a fallacy. Guilt by association is probably a better-known fallacy along this line. In this situation the speaker’s claim is dismissed because the speaker hangs out with people the arguer dislikes. Last in this category is the fallacy that two wrongs make a right – the claimer states his right to do an immoral act because the receiver of the act would have done the same thing: “It’s okay that I slept with her husband; she would do the same with my husband, given the chance.”

The next set of fallacies are the “appeal to…” set.

The bandwagon is the attempt to sway a person’s stance by way of threatening a loss of acceptance by the person’s peers if she does not change her stance. An appeal to tradition claims that something is better simply because it’s older. If the quill pen was good enough for Ben Franklin, it’s good enough for me. This is the logic practiced by someone who foregoes PDAs and computers in favor of paper calendars and notebooks. Often this reasoning is used because of a deep-rooted fear of change, which even the greatest risk-takers should recognize in one form or another. The reverse is an appeal to novelty, reasoning that anything new is superior to older things. With this logic, AIDS would be a preferred illness over the common cold. In the appeal to pity, a person claims that he is speaking the truth because he is suffering. Just because you are a paraplegic does not mean George Washington was a Martian. In the appeal to popularity, a person claims that something is true because it is a popular belief. Sometimes this is true, but there is no guarantee that something is true just because a lot of people think so. The majority is not always right – and rarely silent. Related to that is the appeal to common practice, used often by children with their parents. Parents recognize this fallacy easily and respond, “If the entire seventh grade jumped off a cliff, would you do it too?” However, in adult situations, this is not always so easy to spot.

The appeal to ridicule (or mockery) is an attempt to dismiss an argument by making fun of it. In the appeal to flattery, the arguer tries to make his opponent feel good about himself rather than offer a true argument. “A woman as beautiful as you couldn’t possibly believe I would do anything to harm her.” Well known is the appeal to fear. Instead of offering reasons, the arguer offers a set of dire results if you do not side with him. For instance, if you turn down a date with the boss’s daughter, you might lose your job. The appeal to emotion is another popular one, especially in politics. The politician will “wrap himself in the flag” and use a spate of patriotic terms; if you don’t vote for him, it is tantamount to treason. This type of appeal is tantamount in Facebook when it relates to military, politics, religion or compassion.  How often do you see the challenge that if you don’t share a post then you are not compassionate. In the appeal to consequences of a belief, the argument or reasoning is that if one believes in something (or does not) the consequences will be good or bad;  recognizing true consequences is acceptable, but to deem something true because it has good consequences is bad logic.

The last set of fallacies to be covered here are procedural. Rather than attacking the person, or appealing to something other than fact, procedural fallacies have to do with how an argument is structured. Begging the question is more commonly called circular reasoning. This is where the premises of the argument include the claim that the conclusion is true. I have many friends because I am so popular.

In the biased sample fallacy, the evidence used to back up an argument is prejudicially selected to support the argument. This is most common when using the Internet for proof of an argument. If a person only reads information on right-wing sites, and gets newsletters in e-mail from right-wing organizations, he is only going to have a right-wing set of arguments. Samples need to be balanced out one of three ways – over a significant span of time, from a balanced representation of all sides, or a sample large enough to be a true representation of all things involved and affected. This is one of the most compelling arguments for banning communications monopolies

A red herring is also known as a smoke screen or a wild goose chase and is a well-known tactic. Basically it means to toss in arguments which have no bearing on the issue at hand in an effort to distract the people involved.

Last but not least is the slippery slope. This is an argument which compounds results upon results, none of which are substantiated, until the arguer ends up way out in left field. For example, if you note for Joe Schmoe the first thing he will do is end social security; companies will follow suit and cancel pensions; without social security, medical insurance will disappear; your parents will die; and so on.

“Fallacy” may sound like a fancy word, but by being familiar with the concepts of fallacies, one can more easily judge arguments presented to him as well as more effectively argue back.

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