LOGICAL FALLACIES

Logical fallacies are statements or reasoning which appears to be true until the rules of logic are applied. Some fallacies are used to intentionally persuade or manipulate people through deceptive means, and some fallacies may be used unintentionally in the construction of an argument, without realising it.

The reliability of arguments depends on the context in which those arguments are constructed. Logical fallacies can be used to mislead and deceive people into believing statements that don’t always make logical sense.

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Common

LOGICAL

FALLACIES

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APPEALS TO AUTHORITY

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FALSE INDUCTIONS

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THE SLIPPERY SLOPE

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THE BANDWAGON FALLACY

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THE FALSE DICHOTOMY FALLACY

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THE STRAW MAN FALLACY

The ability to recognise the difference between a sound argument from a false argument is of significant importance in critical thinking. These skills will help us to become less vulnerable to fake news, particularly in the case of social media.

Logical fallacies used in arguments by others can cause us to make decisions that can be harmful to us or others. Intentionally or unintentionally using logical fallacies in our own arguments can make us seem gullible or uninformed and can also make us seem dishonest.

APPEALS

to Authority

This is where we rely on an ‘expert’ source for the foundation of our argument. Mentioning those experts in their fields or academics tend to imply expertise and authority, and makes your argument appear to be backed up by extensive research. The effect of this is even more enhanced when using real names.

The following statements highlight examples of this logical fallacy:

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Claims of a commercial that a particular brand of cereal is the best way to begin each day because athlete Michael Jordan states that this is the cereal he eats every day for his breakfast.

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Commercial claiming that 3 out of 4 dentists recommend a specific brand of toothpaste for their own families to use.

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A book that argues global warming does not exist and cites the research of an environmental scientist who has studied climate change for numerous years.

This form of name-dropping by itself is a weak argument. Even if the ‘expert’ is a true academic with genuine research, it may still not be enough to support an argument. This is because this information may be misunderstood, misquoted or taken out of context.

FALSE

INDUCTION

Drawing false conclusions based on small sample sizes. There is insufficient evidence to support the conclusions that are made.

This logical fallacy causes one to infer a causative relationship where there is no sufficient evidence for such a link. In other words, just because something has happened before something else, does not mean there is a causative and logical link between the two events. Assumptions are made about groups based on inadequate evidence. In these situations, the sample size is often too small to be representative of the entire population. Stereotypes about people or population groups are a common example of false inductions.

The following are examples of the false inductions logical fallacy:

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Every time I take a shower, the telephone rings. Since I’m dying to talk to somebody right now, I should jump in the shower.

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My mother is Irish. She has blond hair. Therefore, everyone from Ireland has blond hair.

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Most of our snowstorms come from the north. It’s starting to snow. This snowstorm must be coming from the north.

Many generalisations can include words like all, ever, always and never. These are words to look out for and then check if there is sufficient evidence to support these statements.

THE

SLIPPERY

SLOPE

The argument that if A happens, it is inevitable that Z will also occur. Therefore, we must prevent A from happening.

The slippery slope argument is dependent upon making one believe that the worst scenario possible is most likely to occur and will certainly occur, is one is to take a particular course of action. In reality, this is not always the case. You are likely to encounter this fallacy in everyday conversation and at times, the argument may appear legitimate. However, upon close inspection, these statements are based upon insufficient evidence and carry weak logical strength.

The following are examples of the slippery slope logical fallacy:

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If we allow Susan to leave early, soon, we’ll be giving everyone Friday afternoons off.

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If women are required to cook while taking care of children, the children will distract the woman, and the kitchen will catch on fire, causing smoke damage not only to the house but also to the woman’s and children’s lungs.

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If we let this child bring the permission slip late, there is no reason to ever set a deadline for anything again!

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If you break your diet and have one cookie tonight, you will just want to eat 10 cookies tomorrow, and before you know it, you will have gained back the 15 pounds you lost.

If an argument involves a series or chain of events, it is important to make sure that each event leading to another is reasonable and makes logical sense.

THE

BANDWAGON

FALLACY

The fallacy occurs when people believe that something must be true because of the fact that the belief is popular.

The Bandwagon Fallacy leads people to believe in an idea or statement simply due to the fact that it is a popular proposition or has significant support associated with it. However, just because lots of people agree with an idea or statement, does not necessarily make it true or right.

Let’s take a look at the following example:

“A survey of all the customers in our store agreed that staying open for 24 hours would be an excellent idea. Therefore, we need to put together a 24-hour schedule as soon as we can.”

Instead of agreeing with an idea straight away, we should ask ourselves some further questions. This way we avoid drawing false conclusions. Taking the context of the example into consideration, we can ask ourselves the following questions:

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Who are these people in our store?

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Would they actually come into the store at 2 am to purchase items? If they are willing to do so, how often would this be?

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What would be the costs versus the benefits of opening the store for 24 hours?

When making such arguments, make sure that you aren’t attempting to get people to agree with what you are saying, just because many others do. It is important to keep in mind that just because lots of people believe in the same idea, does not always mean it is correct and right. We should always attempt to ask ourselves questions about what someone is saying and think critically by applying logic, so we avoid being led on by forceful arguments.

THE

FALSE DICHOTOMY FALLACY

The fallacy occurs when limited outcomes or choices are shown when in reality, there are many more that exists.

This fallacy is reliant on an “either-or” argument in which someone may only give two options, forcing people to choose only between those two options. However, in some situations, neither choice may be the best choice and in fact, there may be many other options that are available. The argument presented makes it seem like the options that are suggested are the only appropriate ones.

The following are examples of the false dichotomy logical fallacy:

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Either people will support the building of the dam, or are they eco-terrorists?

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You can either get married or be alone for the rest of your life.

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Either you support this law which will give the police more power, or you must be a criminal.

It is important to ask ourselves when hearing or making an argument whether the argument only gives two alternatives. If so, are there other alternatives that are feasible yet have not been mentioned? If the answer is yes, we should also include these alternatives or otherwise explain why they should be excluded in the argument.

The fallacy involves distorting the opposition’s argument for the purpose of making it easier to defeat.

THE

STRAW MAN

FALLACY

The Straw Man Fallacy is about portraying the opposition’s argument different to how it really is and then attacking it. This ‘watered-down’ argument is now much easier to defeat than the original argument that the opposition was making.

The following are examples of the straw man logical fallacy:

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He says he is against big banks. He would have us hide all our cash in our beds! That is not only impractical, but it is unsanitary and lacks security.

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A local politician plans to expand the cycle network and add several new speed cameras in densely populated areas. Their opponent states “They want us all to give up driving forever. They are punishing the honest car owners and commuters that help pay these politicians’ salaries.”

By making the argument that the installation of cameras is a direct attack on motorists, the opponent has ‘watered-down’ the argument and made it much easier to respond. This statement is much easier to respond to than to address the actual concerns which relate to an increase in fatalities due to collisions on roads as well as increased pollution levels. In this context, a false argument is created by misrepresentation of the original position of the opposition, so that your own viewpoint appears stronger.

It is important to always attempt to be as accurate as possible when stating your opponent’s argument. Try your best to restate their viewpoint in a way that they would also agree with.

avioding

LOGICAL

FALLACIES

In order to recognise logical fallacies, we must first require a basic understanding of how arguments are formed. Each argument is composed of a series of premises which are simply statements that show your evidence and reasoning. These premises are arranged in such a way that they support the conclusions or claims we are trying to make. We can examine and evaluate whether the premises are valid and if the conclusion follows. The following tips will help to find logical fallacies in arguments of our own or in other peoples’ reasoning and logic:

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Pretend that you disagree with your own conclusion. Instead of defending your argument, change your perspective to the opposition’s viewpoint. Which parts of the argument seem strange to you? Which parts of your argument would be the easiest to attack? These particular parts are ones to give special attention to and strengthen.

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In arguments of others (or your own), look for any name-dropping, generalisations and statements with a long chain of events. Assess the evidence and reasoning behind the conclusions made to evaluate whether they hold their strength or are flawed in their logic.

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List your points for the argument you are making and under each point, state the evidence you have for it. Viewing your conclusions and evidence in this manner will help you to view your points more critically and recognise whether sufficient evidence is present in your claims.

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The more you practice critical thinking using the Street Smarts model, the better you will become in identifying logical fallacies in your own work that you are prone to using. Carefully check your argument for these fallacies. If they are identified, evaluate which points of your argument needs improving and work on strengthening these areas of your argument.

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Assess your characterisations of those with opposing arguments to ensure they are fair and truthful.

In summary, logical fallacies are arguments that may initially sound convincing but are, based upon flawed logic. Logical fallacies can be used to mislead or deceive people into believing conclusions and claims which are incorrect. Recognising logical fallacies is a crucial step to thinking critically. Knowing how to find these in arguments will enable you to evaluate and reconstruct your arguments so that your points carry logic and are backed up by sufficient evidence.