Thinking Logically Relevance Does this sound like a

Thinking Logically: Relevance

Does this sound like a reasonable claim? "We believe that by the government educating women and making it easy for them to find jobs in both the economic and the social fields, we have partly helped them on the road to liberation. We have also set up children’s nurseries to enable mothers to go to work because many husbands insisted that a woman’s duty begins at home. We believe these programs help us progress. "

Well, this guy said it. . . v But that doesn't change the fact that the argument sounds reasonable. -His character is not relevant to the statement's truth.

Relevance If something is relevant it provides evidence either for or against the truth of a claim. Is President Obama a good president? -A duck in China isn’t relevant -The color of his suits aren't relevant. -His ability to pass legislation and interact with other leaders are relevant

A Fallacy Is. . . An error in reasoning. All of the information you have might be true, but you haven't used the information in a logical way. 1. Sadaam Hussein was an insane killer. 2. Sadaam Hussein thought the government should provide childcare to help women work. ________________ Therefore, childcare is evil.

A Fallacy of Relevance is. . . when you are bringing in irrelevant information, evidence that is not important to this discussion. Sometimes bad people have good ideas, bad sources have good outcomes, hypocrites are still right, the majority is wrong, and experts in one area are wrong about other areas.

The Fallacies of Relevance Tu Quoque Straw Man Ad Hominem Genetic Fallacy False Authority Ignoring the Question Red Herring Bandwagon Appeal (Ad Populum)

The Either/Or Fallacy Attacking the character of the person making an argument instead of the argument itself. Ex: "Sadaam Hussein's views on women can't be right because he oppressed political freedom and killed his enemies. "

Tu Quoque ("You too") This attacks the practices of the speaker, accusing him or her of being a hypocrite. Ex: "Michael told me to stop smoking, but he smokes all the time!"

Ad Hominem vs. Tu Quoque Ad Hominem = accuses someone of being a bad person generally. It attacks the character. Tu Quoque = accuses someone of being guilty of hypocrisy, making their argument incorrect.

Ad Hominem or Tu Quoque? You can't get driving directions from Hitler! The man killed millions of people!

Ad Hominem or Tu Quoque? I can't believe that drunk guy told me that alcohol is a terrible drug.

Genetic Fallacy When you consider the source of an idea as relevant to the value of the idea itself. Ex: 1. "Mad Child isn't a good rapper; he's from Canada. " 2. "The new Apple computer is amazing. I know this because Steve Jobs designed it. " 3. "Volkswagens are evil because they were first made by Nazis. "

Question: What do Tu Quoque, Genetic, and Ad Hominem fallacies all have in common?

Answer: What do Tu Quoque, Genetic, and Ad Hominem fallacies all have in common? They all find the source (which includes people) of an idea relevant, they all believe that a bad or good place of origin has an effect on the idea itself.

Bandwagon (Ad Populum) Assumes the truth of a conclusion because the idea is popular. Ex: "One Direction is one of the best selling bands of all time and, therefore, one of the best bands of all time. "

False Authority This fallacy treats someone who has no relevant authority in the field we are discussing as trustworthy. Ex: My physics professor says the United Nations is just a smiley face, so I don’t think I’ll apply to become a UN intern after all.

Question: What do the Bandwagon Appeal and False Authority fallacies have in common?

Answer: What do the Bandwagon Appeal and False Authority fallacies both have in common? They both are based on poor use of ethos. They both trust in people inappropriately.

Straw Man Fallacy (Paper Tiger) Misrepresenting your opponent's argument to make it easier to argue against. Ex: Anyone who isn't a democrat has to explain why he or she doesn't like equality.

Faulty Analogy When you make an unfair comparison. That is, the similarities are not relevant. Ex: Bob: It's important to be proud of your cultural heritage. Joe: That's what white supremacists say.

Question: What do the Straw Man and Faulty Analogy fallacies have in common?

Answer: What do the Straw Man and Faulty Analogy fallacies have in common? They both argue against alternate claims where there aren't enough relevant similarities.

Ignoring the question Changes the subject to focus on a new topic entirely. Ex: "We don't have to worry about saving pandas because homelessness is a much bigger problem. "

Red Herring Fallacy This is when you bring up any irrelevant fact. All of these relevance fallacies are red herring fallacies in some way. We'll call something a red herring when we don't have a more specific name for it (like Ad Hominem) Ex: President Obama needs to pass better gun laws. I mean, he barely passed a decent health care bill.

Red Herring vs Ignoring the Question They are both quite similar. Here's an easy way to keep them separate: Red Herring is like telling someone that a certain piece of information isn't important. Ignoring the Question is like telling someone that they've changed the subject. It's like yelling, "focus!"

The Fallacies of Relevance Tu Quoque Straw Man Ad Hominem Genetic Fallacy False Authority Ignoring the Question Red Herring Bandwagon Appeal (Ad Populum)

Thinking Logically: Causality (figuring out what makes what happen)

First thing's first: It's essential that we are able to tell the difference between causation and correlation.

Correlation A correlation simply describes a consistent relationship between two things. "Whenever X happens this way then Y happens in a similar/different way" - When X increases Y does too -When X increases Y decreases -When X decreases Y does too When X decreases Y increases

Examples of Correlations 1. Generally, students with higher grades like school more. 2. Twice as many accidents occur when you are close to home. 3. Whenever I'm around my grandmother I'm tired.

Examples of Correlations 1. Generally, students with higher grades like school more. It might be that students who enjoy school get better grades because they are having fun and paying more attention or it could be that you'll like school if you get better grades because you'll feel like you're doing a good job

Examples of Correlations 2. Twice as many accidents occur when you are close to home. It might be you are more careless in a familiar neighborhood or it might be that you are close to your home more often than anywhere else.

Examples of Correlations 3. Whenever I'm around my grandmother I'm tired. Hanging out with Granny might be exhausting because of the long drive to her house, the stories she tells, the food she serves, or the fact that she makes you realize that you will grow old one day.

Causation is a more specific type of relationship between two things, when one thing is what makes another thing happen. Y happens because of X.

Examples of Causation 1. I get good grades in school because I study and do my homework. 2. I grow big muscles because I workout all the time. 3. I'm tired at my grandmother's house because she is slowly poisoning me.

Causation or Correlation? Areas with strongest anti-gun laws have highest rates of crime.

Causation or Correlation? Areas with strongest anti-gun laws have highest rates of crime. Correlation: It might be that strong gun laws increase crime OR that places with higher crime need stricter laws.

Causation or Correlation? President Obama became president and the economy crashed.

Causation or Correlation? President Obama became president and the economy crashed. Correlation: The recession occurred due to numerous causes that started well before Obama's presidency.

Causation or Correlation? The water level is rising because icebergs and snow are melting.

Causation or Correlation? The water level is rising because icebergs and snow are melting. Causation: The water level is rising because of more ice melt. Without this melting the water level would not be rising.

The Fallacies of Causality Post Hoc Slippery Slope

Post Hoc Fallacy (Part 1) "Post Hoc" is short for Post Hoc Ergo Propter Hoc, which means, "After this, therefore because of this. " Basically it means, "X happened after Y? Well then X must have caused Y. " It's a fallacy where you inappropriately identify the cause.

Post Hoc Fallacy (Part 2) More often than not this fallacy is going to include confusing a correlation for causation. "The rooster crowed and the sun rose. Therefore, the rooster caused the sun to rise. " "Every time I drink gatorade I win a game. Therefore, gatorade causes me to win games. "

True Causal Chain (not Slippery Slope) If hanging out with certain friends means that you will do heroin, and doing heroin disqualifies you from joining the FBI, and your goal is to join the FBI, then you shouldn't hang out with those friends. True! If A leads to B and B leads to C and C is bad Then don't do A!

Slippery Slope Fallacy (Part 2) A slippery slope fallacy occurs when you think there will be a causal chain when there won't necessarily be. "If you don't do your homework today, you'll end up poor and alone" "If we let the Communists take over Nicaragua or El Salvador, pretty soon they will be in other countries like Guatemala and Honduras. Soon all of Central America will be Communist. "

"If you don't do your homework today, you'll end up poor and alone" It's possible that not doing your homework today is the first step towards ruining your life, but it's also possible that you do make up work, get good grades, and lead a happy life.

"If we let the Communists take over Nicaragua or El Salvador, pretty soon they will be in other countries like Guatemala and Honduras. Soon all of Central America will be Communist. " It's possible that communism will spread, but it's also possible it won't and will stay localized to those countries.

Slippery Slope or True Causal Chain? "First we gave several days off at Christmas, then we agreed to sick days, then we were talked into a day off if someone got married. Pretty soon they’re going to want Earth Day declared a holiday, and eventually they’ll ask for a day off to celebrate their bird’s birthday! I tell you we should have stopped with Christmas".

Slippery Slope or True Causal Chain? "First we gave several days off at Christmas, then we agreed to sick days, then we were talked into a day off if someone got married. Pretty soon they’re going to want Earth Day declared a holiday, and eventually they’ll ask for a day off to celebrate their bird’s birthday! I tell you we should have stopped with Christmas. " Slippery Slope: Just because we have Christmas as a holiday doesn't mean that it will lead to those crazy conclusions. We can just have a few days off and stop there.

Slippery Slope or True Causal Chain? "If nobody recycles then landfills will grow and pollution increase. If pollution increases then your children will be raised in a dirtier, less healthy world. If you want to improve the planet for your children, then you should do your part and recycle. "

Slippery Slope or True Causal Chain? "If nobody recycles then landfills will grow and pollution increase. If pollution increases then your children will be raised in a dirtier, less healthy world. If you want to improve the planet for your children, then you should do your part and recycle. " True Causal Chain: By not recycling you are increasing long term pollution (even if only a little bit).

The Fallacies of Causality Post Hoc Slippery Slope

Thinking Logically: Errors of Truth

The Fallacies of Truth The Either or Fallacy (False Dichotomy) The fallacy of composition The fallacy of division The Gambler's Fallacy Equivocation

Either/Or (False Dichotomy) A dichotomy is when something is divided into two parts. A false dichotomy is when you are given two options and there actually more. ex: You can either marry me or die alone. -This is not true because you can always meet someone on the internet.

False Dichotomy or True Dichotomy? You are either dead or alive.

False Dichotomy or True Dichotomy? You are either dead or alive True! You can't be in between. You are either one or the other.

False Dichotomy or True Dichotomy? You are either pregnant or not.

False Dichotomy or True Dichotomy? You are either pregnant or not True! There's no "kinda pregnant" state.

False Dichotomy or True Dichotomy? You are either with us or against us.

False Dichotomy or True Dichotomy? You are either with us or against us. False dichotomy! You can be on nobody's team and be neutral.

False Dichotomy or True Dichotomy? You either like Pepsi or Coke.

False Dichotomy or True Dichotomy? You either like Pepsi or Coke False dichotomy! You can hate both of them or like both of them.

The fallacy of composition Composition is when you put things together The fallacy of composition occurs when you believe that something about the parts will be true of the whole. ex: Putting the five best rappers into a group will make a band five times better than they would be alone

The fallacy of division Division is when you break things apart. The fallacy of division occurs when you believe something that is true about the whole will true about the parts. ex: Mr. X is a member of the best hip hop group on earth. This means he must be one of the best hip hop musicians.

Fallacy of division or composition? Mike is from my least favorite class, so I know he's a bad kid.

Fallacy of division or composition? Mike is from my least favorite class, so I know he's a bad kid. Fallacy of division. I assume that just because the class as a whole was bad he was bad. He might have just been in a class with a lot of bad apples the ruined the lot.

Fallacy of division or composition? This is such a large hotel. I'm sure the rooms will be big.

Fallacy of division or composition? This is such a large hotel. I'm sure the rooms will be big. Fallacy of division. Just because the whole place is big, doesn't mean its parts (rooms) will be big.

Fallacy of division or composition? Of course it's a great novel. Every page is full of beautiful language.

Fallacy of division or composition? Of course it's a great novel. Every page is full of beautiful language. Fallacy of Division! Every page may have beautiful language, but that doesn't mean it will all fit together to make a great novel.

Fallacy of division or composition? If we get the best engineers from each country we will have the best company.

Fallacy of division or composition? If we get the best engineers from each country we will have the best company. Fallacy of Division! Just because they were the best in their country does not mean that they will work well together.

The Gambler's Fallacy This fallacy rests on a misunderstanding about how statistics work. The gambler's fallacy assumes that the likelihood of an outcome will increase over time when it actually won't ex: I flipped a coin and I got five heads in a row. It's really likely that it will be tails next.

Gambler's Fallacy or Good statistics? Every day I drive I am less and less likely to get an accident because I become more experienced.

Gambler's Fallacy or Good statistics? Every day I drive I am less and less likely to get an accident because I become more experienced Good! It's true that experience makes you less likely to get in an accident. This counts, of course, until you get really old.

Gambler's Fallacy or Good statistics? I've missed every basket today. I'm really likely to get one soon.

Gambler's Fallacy or Good statistics? I've missed every basket today. I'm really likely to get one soon. Gambler's fallacy. The likelihood doesn't go up over time. You might just be no good, rogue. **Now, if the reasoning was that he was getting better because of practice that would be different.

Equivocation To equivocate means to abuse two words that have the same sound (homonym). Equivocation occurs when you treat two words as one to prove your argument inappropriately. ex: A feather is light. What is light cannot be dark. Therefore, a feather cannot be dark.

Which word is being equivocated? The sign said, "fine for parking" here, so I assumed it was fine to park there.

Which word is being equivocated? The sign said, "fine for parking" here, so I assumed it was fine to park there. Fine = A ticket/charge Fine = It's okay

Which word is being equivocated? Nobody's perfect and I'm a nobody. Therefore, I'm perfect.

Which word is being equivocated? Nobody's perfect and I'm a nobody. Therefore, I'm perfect. Nobody = No people Nobody = A not important person

The Fallacies of Truth The Either or Fallacy (False Dichotomy) The fallacy of composition The fallacy of division The Gambler's Fallacy Equivocation

Thinking Logically: Circular Reasoning

A premise and a conclusion Arguments consist of two things: the thing you are trying to prove and the things you say to try and prove it. Conclusion = What are you trying to prove Premise = The claims you use to prove the conclusion

A premise and a conclusion (Part 2) Here's a good example with premises and conclusions: Premise #1: All dogs are related to wolves Premise #2: Bob is a dog _________________ Conclusion: Bob is related to a wolf

A premise and a conclusion (Part 3) Here's another example that isn't deductive: Premise #1: When there's a red sky at sea it usually means a storm Premise #2: There's a red sky at sea _________________ Conclusion: There's probably a storm coming

Circular Reasoning ("Begging the Question") Circular reasoning is when your conclusion doesn't prove anything new because the premises already assume it is true. In other words, your premises are every bit as controversial as the conclusion you are advocating.

Circular Reasoning Example "You should exercise because it's good for you" This basically says, "You should exercise because you should exercise. "

Circular Reasoning Example? "You can't give me a C! I'm an A student!"

Circular Reasoning Example? "You can't give me a C! I'm an A student!" Circular! The speaker is saying that they can't get a C because they aren't a person who gets Cs.

Circular Reasoning Example? "The Pope is infallible. Therefore, everything he says is true. "

Circular Reasoning Example? "The Pope is infallable. Therefore, everything he says is true. " Circular! Being infallible is the same thing as always being right.

Circular Reasoning Example? "If I had money to open my business I could use it to provide more services and ultimately make more money!"

Circular Reasoning Example? "If I had money to open my business I could use it to provide more services and ultimately make more money!" Nope! This reasoning is plausible. Even if you disagree, it isn't circular.

Circular Reasoning? Premise #1: If you have enough willpower then you can quit smoking. Premise #2: Having enough willpower just requires a strong enough desire, which anyone can have. ____________________ Conclusion: Anyone can quit smoking

Circular Reasoning? Premise #1: If you have enough willpower then you can quit smoking. Premise #2: Having enough willpower just requires a strong enough desire, which anyone can have. ____________________ Conclusion: Anyone can quit smoking Circular! The premises assume that anyone can quit (because anyone can want to) but that doesn't really prove anything new.

Circular Reasoning? Premise #1: Everything must have a cause Premise #2: The cause of everything must have a name ____________________ Conclusion: God must exist

Circular Reasoning? Premise #1: Everything must have a cause Premise #2: The cause of everything must have a name ____________________ Conclusion: God must exist Circular! You may think it's right, but that doesn't change that premise #1 assumes the truth of the conclusion. Saying something is circular doesn't mean it's wrong, just that you haven't proved anything.