Logical Fallacies and Analysis
| Learning Objective: - Identify logical fallacies relating to analysis.
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LESSON
A logical fallacyA mistake in reasoning; faulty thinking that weakens an argument or leads to an incorrect conclusion. is faulty reasoning upon which an ideaA thought, opinion, or impression., theoryIn science, a well tested and widely accepted explanation for a phenomenon. Theories incorporate facts, observations, experiments, laws, and careful reasoning. In more general usage, theory may merely mean an unproven idea, speculation, or guesswork., thesisAn overall argument, idea, or belief that a writer uses as the basis for a work., or hypothesisA preliminary explanation that needs further study before it can be accepted. A hypothesis is stronger than a guess but less supported than a theory. is based. This is especially important when analyzingTo make a thoughtful and detailed study of something. other people's writing. Should you rely upon an author's thoughts and argumentsA set of statements or reasons making a case for or against something. as evidenceFacts, statistics, or expert testimony that supports a claim. in an essayA short piece of writing that focuses on at least one main idea. Some essays are also focused on the author's unique point of view, making them personal or autobiographical, while others are focused on a particular literary, scientific, or political subject. , an unidentified logical fallacy can weaken your writing and undermine your entire thesis statementA brief statement that identifies a writer's thoughts, opinions, or conclusions about a topic. Thesis statements bring unity to a piece of writing, giving it a focus and a purpose. You can use three questions to help form a thesis statement: What is my topic? What am I trying to say about that topic? Why is this important to me or my reader?.
In this lesson, you will be introduced to eight common logical fallacies.
- Circular reasoning: Supporting an argument by restating the argument.
I did not deserve a D on the paper because I have always been an A+ student.
- Bandwagon appeal: Implies that because the majority of people believe that X is true then it must be valid because so many people believe it.
You should use Clean and Fresh shampoo because it is the number one selling shampoo in the United States.
- Ad hominem: An attack on a person's character and personal traits to weaken his or her argument.
That man is not competent to run for city council; he was arrested when he was a teenager for underage drinking and public intoxication.
- Red herring: Claims that are misleading to distract from the argument at hand.
Can you believe that the cop pulled me over for going five miles over the speed limit? Police need to spend all their time getting the really dangerous offenders off the street, like murderers.
- Non sequitur: A conclusion that is disconnected from the premise that precedes it.
The moon landing must have been faked. There are "photos" of fairies and the Loch Ness monster.
- False analogy: A claim that since A is like B, A has the same properties that B has.
I loved the Harry Potter series by JK Rowling so much that I am sure that I will love her newest book.
- Hasty generalization: Coming to a conclusion with the briefest look at the evidence.
I just saw the inside of my accountant's car, and it was an absolute mess. I am not sure we should hire her to be our CPA; she would be as careless with our finances.
- Moral equivalence: A claim that compares A with B to prove that A is as bad or good as B.
You might want to think twice before going out with Justin; his brother has a new girlfriend every two weeks.
+ PRACTICAL APPLICATIONBeing able to identify logical fallacies is a useful and important skill in the classroom as well as the workplace. Not only will you need to be able to spot them in other writers' works, you must ensure you are familiar with them so that you do not rely upon faulty reasoning in your own writing.
Advertising and politics are two fields that are particularly prone to the use of logical fallacies. How many advertisements have you seen that suggest if you use or consume a product you will be more desirable, successful, or popular, even if the product is only a vacuum cleaner? How many politicians' speeches have you heard where they attacked their opponents' character? Political action committees, or PACs, are particularly adept at marrying advertising and politics to promote their agendas.
Being familiar with different kinds of logical fallacies will help you avoid them in your own writing and spot them in your everyday life. You may be surprised how often they occur. They are not always deliberate attempts to deceive, but they are always illogical.
Here are examples of each of the eight logical fallacies, followed by an explanation of how the logical fallacy is used in each specific example.
- I hate skiing, so I am pretty certain I will never like Colorado.
This is an example of a false analogy fallacy. It is a claim that because A (skiing) is related to B (Colorado), A has the same properties that B has. In actuality, while Colorado is a popular skiing destination and often associated with the sport, Colorado offers far more than just skiing.
- My doctor died from lung cancer. He must have smoked and been a really unhealthy person. He was also likely a terrible physician.
This is an example of a hasty generalization fallacy. The person has come to quick and unreasoned conclusions about the physician because he died from a disease that can be caused by many factors other than smoking, such as genetics or perhaps just bad luck.
- If speeding wasn't illegal, it wouldn't be forbidden under state or federal law.
This is an example of a circular reason fallacy. It tries to support the argument that speeding is illegal because it is illegal.
- I just don't trust my student, Jessica. Her best friend, Rachel, has plagiarized two separate assignments.
This is an example of a moral equivalence fallacy. It is a claim that compares the character of one student, Jessica, with that of another, Rachel, to assert that the student is untrustworthy.
- My roommate says I don't clean up around our apartment enough, but he is failing all of his courses.
This is an example of a red herring fallacy. It claims that the roommate's opinion is wrong by trying to distract with the argument that he is a poor student.
- My parents grew up in Pennsylvania; that's why they are so strict.
This is an example of a non sequitur fallacy. The conclusion that the person's parents are strict is disconnected from the preceding premise that they were raised in Pennsylvania.
- Don't worry about the no parking signs on the street; everybody always parks here after five o'clock.
This is an example of a bandwagon appeal fallacy. It implies that because the majority of people fail to heed the signs, it is an accepted practice. In reality, it is still a forbidden practice.
- That coach tells his players to get eight hours of sleep every night and eat healthy foods, but I know he eats fast food twice a week.
This is an example of an ad hominem fallacy. It is an attempt to weaken the coach's argument for eating well and getting rest by attacking his own fast food habit.
Read each example and determine which of the eight logical fallacies presented in this lesson is used and why.
- My experience with diverse populations in my neighborhood committee will serve me well during my experience abroad.
Which logical fallacy is used?
This is an example of a non sequitur fallacy.
Explain your answer.
The two situations are dissimilar enough that there is no logical point of comparison.
- I don't know why anyone goes to that church on Sunday when we all know the pastor cheated on his taxes last year.
Which logical fallacy is used?
This is an example of an ad hominem fallacy.
Explain your answer.
It is an attempt to weaken the position of a religious figure by attacking his personal character.
- Everyone I know at the company rounds up the number of hours they work each week to reach the required forty hours. Management doesn't really care.
Which logical fallacy is used?
This is an example of a bandwagon appeal fallacy.
Explain your answer.
This implies that because many people falsify their time cards then it must be true and therefore is okay with management.
- My friend drives a Porsche and lives in a luxury loft building; he must have won the lottery.
Which logical fallacy is used?
This is an example of a hasty generalization fallacy.
Explain your answer.
The conclusion that the person won the lottery because he drives an expensive automobile and lives in a pricey home is hasty. In actuality, there are a number of potential explanations.
- That new restaurant is owned by the same people who own that slow, overpriced dry cleaners downtown; the service is probably lousy and the food awful.
Which logical fallacy is used?
This is an example of a false analogy fallacy.
Explain your answer.
It is a claim that because the restaurant and dry cleaners share the same owners, they must also share the same negative characteristics.
- You save more money when you shop at Ben's Big Box because that's what the ads say.
Which logical fallacy is used?
This is an example of a circular reason fallacy.
Explain your answer.
This is an attempt to support the argument that Ben's Big Box is cheaper than its competitors because its own jingle says so.
- There's no way we can trust him with the company budget; he had to file for bankruptcy after his ex-wife got all their assets in the divorce.
Which logical fallacy is used?
This is an example of a moral equivalence fallacy.
Explain your answer.
It is a claim that compares the businessman's ability to manage company finances with his inability to control the financial outcome of a divorce in order to prove that he will not be able to manage the company budget.
- There's no way we can elect a politician with such outmoded economic plans. Not to mention she also has been involved in some scandals.
Which logical fallacy is used?
This is an example of a red herring fallacy.
Explain your answer.
The claim that this person running for office has been involved in some unspecified scandals is intended to mislead and distract from a debate about her economic plans.
How can identifying logical fallacies aid your reading process?
Identifying logical fallacies can aid your reading process by helping you to quickly spot the faulty reasoning and unsupported arguments of other writers. In turn, this will help you rule out certain texts as evidentiary sources for your own writing as well as strengthen the arguments you make discrediting that particular writer's ideas, thoughts, and opinions.
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