Logical Fallacies

• Logical fallacies are errors in reasoning based on poor or faulty logic.
• Logical fallacies in formal arguments can damage a writer's credibility

False Dilemma

• A false dilemma is an argument that assumes only two options or outcomes exist when there are more.
• Example: Jack finished the exam early, so he either knew all the answers or none of them.
• Example: Devote yourself to the company fully or quit.

Appeal to Ignorance

• Appeal to Ignorance is believing a claim is false (or true) simply because it hasn't been proven otherwise.
• Example: Scientists can't prove humans evolved, therefore the Genesis creation account is literally true.
• Example: Fairies must live in the attic since nobody has proven they don't.

Slippery Slope

• Slippery slope arguments assume one event will trigger a chain of events, leading to an extreme and undesirable conclusion.
• Example: If Jack doesn't turn in his paper, he will fail, his GPA will suffer, he won't get into grad school, and he'll never achieve his dreams.
• Example: School uniforms will cause less shopping at local clothing stores, which closes the stores and hurts the economy.

Complex Question

• A complex question is a trick question that presupposes an unverified assumption the person being questioned is likely to disagree with.
• Example: Asking someone, "Have you stopped cheating on tests?" presupposes they were cheating.
• Example: The question "Have you stopped mistreating your pet?" implies the person was mistreating their pet.

Appeal to Force

• Appeal to force is a logical fallacy where someone uses threats or intimidation.
• Intimidation is used to force another party to drop their argument.
• Example: If you don't support the tax reformation bill, your chances of re-election will be low.
• Example: Be back by 6 pm - remember what happened last time you were out late.
• Example: Agree with me or I'll beat you up.

Appeal to Pity

• Appeal to pity is when you attempt to convince someone by making them feel sorry for a person or situation.
• Example: A student asks for an A on a paper due to trouble they have been through, like a computer crash, noisy lab, and a traffic ticket.
• Example: A student asks professor to raise their grade due to a terrible semester that included a broken car, stolen laptop, and a sick cat.

Appeal to Consequences

• Appeal to consequences argues something can't be true because the consequences of it being a reality would be unacceptable.
• Example: A patient says they can't have cancer because it would mean they won't see their kids get married.
• Example: Someone doesn't believe in reincarnation because they don't want to come back as someone or something else.

Bandwagon

• Bandwagon is claiming an idea should be accepted because many people believe it's true or favor it.
• It describes believing something is true or acceptable only because it is popular.
• Example: Cathy feels she needs to create a social media account because her friends have joined social media sites, even though she prefers face-to-face conversations.
• Example: It is fine to wait until the last minute to write your paper because everyone does it.

Attacking the Person (Ad Hominem)

• Attacking the person (Ad Hominem) means “against the man."
• Ad Hominem is also known as name-calling or the personal attack fallacy.
• This is attacking the person making the argument instead of the argument itself.
• Example: "He's so evil that you can't believe anything he says."
• Example: "You can't trust what he says about the economy, he lost his job last year."

Appeal to Authority

• Appealing to authority inappropriately involves getting people to agree by citing a supposed authority who isn't really and expert.
• It does not accurately cite a legitimate expert on the matter.
• Example: Gun laws should be strict because actor Brad Pitt supports it.
• Example: All carbs are bad because a nutritionist wrote a book saying they are.

Anonymous Authority

• Anonymous authority is a type of appeal to authority where the authority in question isn't named.
• The fallacy is common enough to warrant special mention.
• Without a named authority, it's impossible to confirm if they are an expert.
• Example: Experts agree that the best way to prevent nuclear war is to prepare for it.
• Example: If you swallow gum it takes seven years to digest, so don't do it.

Post Hoc:

• Post hoc is also described as the "too much of a coincidence" argument.
• Post hoc is assuming that because one thing happened at the same time or right after another, the first caused the second.
• Example: A tennis player eats chicken before a game and wins, so he eats chicken before every game.
• Example: AIDS emerged when disco was popular, so disco caused AIDS.

False Analogy

• False analogy is a fallacy that incorrectly compares two things in order to draw a false conclusion.
• Example: Joan and Mary drive pickup trucks, and Joan is a teacher, so Mary must also be a teacher.
• Example: Bananas and telephones are shaped to fit human hands, so bananas were created for humans.
• Example: Addiction to drugs can ruin someone's life, so addiction to computer games can also ruin your life.

Accident

• Accident applies a general rule to all situations, even when there are clear exceptions.
• The fallacy is also known as destroying the exception, because the rule should not apply in an exceptional case.
• Example: Taking a life is morally wrong, therefore termite control is a crime.
• Example: All birds can fly; penguins are birds, so penguins can fly.

Hasty Generalization

• Hasty generalization is an argument based on insufficient evidence.
• It is often caused by a sample that is too small or not representative of the population.
• Example: Jack was late to his first two meetings, so he must be chronically late.
• Example: I felt sick after eating pizza twice, so something in Georgio's pizza must make me allergic.

Wrong Direction

• Wrong direction occurs when two happenings occur together.
• The real cause is mistaken for the effect and the effect is mistaken for the cause, reversing them.
• Example: He was speeding because he got a ticket.
• Example: Kids play video games, and video game make children violent.
• Example: Cancer causes smoking.

Complex Cause

• Complex cause is a fallacy that incorrectly assumes one event causes another.
• This is a mistake of a time connection for a cause-effect connection.
• Example: Every time I wash my car, it rains.
• Example: The poor location of a bush, the driver was drunk and the pedestrian being drunk all led to the accident.
• Example: People are afraid due to increased crime making break the law more.

Irrelevant conclusion

• Irrelevant conclusion is an argument that may be logically valid, but fails to address the actual issue in question.
• Example: The house across the street is for sale; the owners must have lost their money gambling
• Example: Hippos are not dangerous because they are so calm and cute.

Straw Man

• Straw man is a logical fallacy that misrepresents an opponent's argument or position.
• The misrepresentation makes it easier to attack the position.
• Example: Those who seek to abolish the death penalty are seeking to allow murderers to commit heinous crimes without consequence.
• Example: When a teacher proposes more time on math exercises, a parent complains that the teacher doesn't care about reading and writing.

Affirming the Consequent

• Formal logic error occurs if the consequent (result) is true then the antecedent (cause) is true.
• Example: If taxes are lowered, I will have more money. I have more money, so taxes must have been lowered.
• Example: If it rains, the game is canceled, so if the game is canceled it rained.
• Example: If the phone is off, it will not ring, so if it will not ring then the phone is off.

Denying the Antecedent

• Denying the antecedent is a fallacy in formal logic where the antecedent (the “if” part) is not true.
• It wrongly concludes that the consequent (the "then" part) also cannot be true.
• Example: If it barks, it is a dog. It doesn't bark, therefore, it's not a dog.
• Example: If I study hard, I will pass the test. I didn't study hard, so I will fail the test.
• Example: If someone is a professor, then they have a PhD. Maria is not a professor, so Maria does not have a PhD.

Inconsistency

• Inconsistency happens when someone makes two claims in an argument that cannot both be true simultaneously.
• It's a logical flaw presenting conflicting statements that undermines their argument.
• Example: "Nobody goes there anymore. It's too crowded." - Yogi Berra
• Example: "Everyone should speak their mind freely, but it's best to always keep your thoughts to yourself."
• Example: "The government should not interfere in people's lives, but we need stricter laws against drug use."