Introduction and Activities

Slides:



Advertisements
Similar presentations
Logical Fallacies. What is a logical fallacy? A fallacy is an error of reasoning. These are flawed statements that often sound true Logical fallacies.
Advertisements

Argumentation.
Understanding Logical Fallacies
Logical Fallacies.
Logical Fallacies Introduction.
Logical Fallacies Persuasion Pitfalls. Logical Fallacies What is a logical fallacy? A mistake in reasoning that seriously affects the ability to argue.
Logical Fallacies AKA “How NOT to Win an Argument”
How to make an Argument Toulmin Model.
Logical Fallacies Introduction. What is a logical fallacy? A fallacy is an error of reasoning. These are flawed statements that often sound true Logical.
 Read the following argument. Examine it closely. Do you think it is logically sound? Why?  [T]he acceptance of abortion does not end with the killing.
Introduction and Activities
Fallacies Information taken from Purdue OWL, Nancy Wood’s Perspectives on Argument and Annette Rottenberg’s Elements of Argument.
Flawed Arguments COMMON LOGICAL FALLACIES.  Flaws in an argument  Often subtle  Learning to recognize these will:  Strengthen your own arguments 
 In this task you will see 16 different arguments.  You have to identify which of the 8 common fallacies is being used by the argument.
Odds and ends from the last EOC practice…
Age of the Sage Advertising, Inc. “I cannot teach anybody anything; I can only make him think.” Socrates.
Get Notebooks! What is a fallacy?  A fallacy is an error in reason  May be accidental or intentional  In arguments or propaganda, they are often used.
Logical Fallacies Notes. What is a Logical Fallacy? A fallacy is an error in reasoning. These are flawed statements that often sound true. What does it.
Recognizing Logical Fallacies A logical fallacy is a mistake in logical thinking; it is a MENTAL TRAP.
Introduction and Activities
Reason: as a Way of Knowing Richard van de Lagemaat, Theory of Knowledge for the IB Diploma (Cambridge: CUP, 2005)
INFORMAL FALLACIES. FALLACIES OF RELEVANCE Errors resulting from attempts to appeal to things that are not relevant, i.e., not really connected to or.
American Literature Research Paper. » An effort to understand how people attempt to influence others through language and symbolic action » This includes.
LOGICAL FALLACIES. A logical fallacy is an error of reasoning. When someone adopts a position based on a bad piece of reasoning, they commit a fallacy.
INFORMAL FALLACIES The aim of this tutorial is to help you learn to recognize and resist fallacious arguments.
Let’s see some more examples!
Logical Fallacies.
Chapter Two: Good Reasoning Review Applying Ethics: A Text with Readings (10 th ed.) Julie C. Van Camp, Jeffrey Olen, Vincent Barry Cengage Learning/Wadsworth.
Logical Fallacies When arguments go bad… Image:
Look for these in the arguments of others and avoid them in your own arguments.
LOGIC 2+2=4… right?. Logical Reasoning Statements formed from sound thinking and proof of reasoning.
Fallacy An error of reasoning based on faulty use of evidence or incorrect interpretation of facts.
Fallacies The quickest ways to lose arguments. Introduction to Logic O Argument: The assertion of a conclusion based on logical premises O Premise: Proposition.
LOGICAL FALLACIES.  What is a logical fallacy? A logical fallacy is a mistake made when arguing a claim or argument because the speaker/author has incorrectly.
Errors in Reasoning. Fallacies A Fallacy is “any error in reasoning that makes an argument fail to establish its conclusion.” There are two kinds of fallacies.
Chapter Two: Good Reasoning Applying Ethics: A Text with Readings (10 th ed.) Julie C. Van Camp, Jeffrey Olen, Vincent Barry Cengage Learning/Wadsworth.
Logical Fallacies A logical fallacy is an element of an argument that is flawed If spotted one can essentially render an entire line of reasoning invalid.
Rhetorical Fallacies Purdue OWL.
Persuasive Text And Fallacies of Argument What does it mean to be persuasive? 4 When you are persuasive you talk someone into doing something or into.
Fallacies Mistakes in reasoning or thinking.  Occurs when a speaker makes a claim that presents a range of choices.  Writers that use either/or are.
Common Logical Fallacies Flawed Arguments. Logical Fallacies… Flaws in an argument Often subtle Learning to recognize these will: – Strengthen your own.
Common Logical Fallacies FLAWED ARGUMENTS SUBTLE ERRORS IN JUDGEMENT AND CONSTRUCTION.
EVALUATING ARGUMENTS AND BUILDING ARGUMENTS ENGL 121 Howard Community College.
Ad Hominem (Personal Attack) An attempt to discredit the argument by discrediting the character of the person advancing it.
Rhetorical Fallacies A failure in reasoning that renders an argument invalid. Faulty reasoning, misleading or unsound argument.
Talking points 1. Would Neil still have committed suicide if Mr. Keating had never come into his life? Who is most to blame for Neil’s death? Mr. Keating?
Logical Fallacies. Slippery Slope The argument that some event must inevitably follow from another without any rational claim. If we allow A to happen.
Logical Fallacies Introduction.
College English Yichun Liu
Logical Fallacies.
Relevance Premises are relevant to the conclusion when the truth of the premises provide some evidence that the conclusion is true Premises are irrelevant.
Logical Fallacies.
Common Logical Fallacies
Propaganda and Logical Fallacies
Errors in reasoning that invalidate the argument
Common Logical Fallacies
More on Argument.
C/Maj Nicholas Schroder
Appeal to Force (Argumentum ad baculum)
Writing the Argumentative Essay
Chapter 14: Argumentation
Introduction and Activities
More on Argument.
Logical Fallacies Introduction.
Chapter 6 Reasoning Errors
Logical Fallacies Introduction.
Common Logical Fallacies
Logical Fallacies Introduction.
Introduction and Activities
Logical Fallacies Introduction.
Presentation transcript:

Introduction and Activities Logical Fallacies Introduction and Activities

What is a logical fallacy? A fallacy is an error of reasoning. These are flawed statements that often sound true Logical fallacies are often used to strengthen an argument, but if the reader detects them the argument can backfire, and damage the writer’s credibility

You are going to lunch detention because I said so. Students who talk get written up. Even though I asked you a question, you were talking, so you will get written up. If you get caught with a cell phone, you'll have to pay 20 dollars, which means you won't have money for lunch, so you'll lose weight and will get hurt on the football field. Goths wear black. Dr. Stroud is wearing black. Dr. Stroud must be a goth. I don't have to do what Mrs. House says. She's not even a real teacher this year.

Origins The word “fallacy” may derive from the Latin word fallere meaning, “to deceive, to trip, to lead into error or to trick.” The word may also derive from the Greek phelos, meaning “deceitful.” Like any other form of reasoning, it can be deductive or inductive www.sun-design.com/talitha/fallacies.htm

Deductive Goes from general to specific All numbers that are divisible by 5 end in either a 5 or a 0. Therefore, since 4730160 ends in a 0, 4730160 is divisible by 5.

EXAMPLES (IF-THIS-THEN-THAT) If all tulips are plants (premise 1) And if all plants produce energy through photosynthesis (premise 2) Then all tulips must produce energy through photosynthesis (conclusion)

Tom is allergic to peanuts. This candy has peanuts in it.  Tom should not eat this candy. If you can re-word the "given" in terms of all, and the "conclusion" in terms of one, then you have deductive reasoning.  Using example #2, for instance, I could have re-worded it as "All peanuts make Tom sick.  This one candy has peanuts in it.  Therefore, this one candy will make Tom sick."

Deductive reasoning doesn’t always prove correct though…. Christopher Columbus and the rest of the old world held the belief that the world was flat. If the earth is flat (premise 1) Then it should have boundaries (premise 2) If it has boundaries, we will fall off if we go too far (conclusion)

Inductive Reasoning Starts in the specific and goes out to the general. On Monday, the sun came up in the morning.  On Tuesday, the sun came up in the morning.  On Wednesday, the sun came up in the morning.  Therefore, the sun must come up every morning.

EXAMPLES: (Specific to Whole) A baby drops a cracker from his or her highchair The cracker falls to the floor The baby repeats this until it learns it happens every time Eventually, the baby applies this logic to other items such as toys and bottles The baby learns every items that is dropped from high chair will fall to the floor

Why study logical fallacies? It is important to develop logical fallacy detection skills in your own writing, as well as others’. Think of this as “intellectual kung-fu: the art of intellectual self defense.” (Logical Fallacies Handlist)

Types of Logical Fallacies The following slides will briefly explain various categories under which logical fallacies can be divided. Each slide contains one example from that category; please keep in mind there are many kinds of fallacies in each category. For a comprehensive list see the following websites: http://sun-design.com/talitha/fallacies.html http://owl.english.purdue.edu/handouts/general/gl_fallacies.html www.datanation.com/fallacies/index.htm

Types of Logical Fallacies Fallacies of Relevance “Bandwagon Approach” “It must be cool because everyone is doing it…”

The bandwagon is coming by, don’t miss it, or you will be left behind! Popularity fallacy, bandwagon appeal

Types of Logical Fallacies “Slippery Slope” “If you don’t stop smoking cigarettes, then you are going to start shooting heroin.” “Appeal to Fear” “If you don’t stop using drugs, you’re going to end up like this.”

"We've got to stop them from banning obscene websites in schools "We've got to stop them from banning obscene websites in schools. Once they start banning one form of literature, they will never stop. Next thing you know, they will be burning all the books!" Example of Slippery Slope Slippery slope

Slippery Slope Slippery Slope Definition: In order to show that a proposition P is unacceptable, a sequence of increasingly unacceptable events is shown to follow from P. A slippery slope is an illegitimate use of the"if-then" operator. Examples: You should never gamble. Once you start gambling you find it hard to stop. Soon you are spending all your money on gambling, and eventually you will turn to crime to support your earnings.

Slippery Slope Some people argue that one thing will directly lead to another and on and on. This is error in thinking. Example: If you get caught with a cell phone, you'll have to pay 20 dollars, which means you won't have money for lunch, so you'll lose weight and will get hurt on the football field.

Appeal to Force or Fear Appeal to Force/Fear (argumentum ad baculum) Definition: The reader is told that unpleasant consequences will follow if they do not agree with the author. Examples: 1. You had better agree that the new company policy is the best bet if you expect to keep your job. 2. NAFTA is wrong, and if you don't vote against NAFTA then we will vote you out of office. 3. If you don’t support the party’s tax plan, you and your family will be reduced to poverty.

Beware of TV Appeal to fear

Appeal to Fear Some people construct their argument to scare people into believing it. Examples: Onstar: “What if you wreck and can’t call from you cell phone? Who would come?” You need Onstar. President Obama is going to destroy healthcare don’t listen to what he as to say!

Ad Hominem Ad hominem /Attacking the Person An ad hominem argument is any that attempts to counter another's claims or conclusions by attacking the person, rather than addressing the argument itself. True believers will often commit this fallacy by countering the arguments of skeptics by stating that skeptics are closed minded. Skeptics, on the other hand, may fall into the trap of dismissing the claims of UFO believers, for example, by stating that people who believe in UFO's are crazy or stupid.

False Dilemma False Dilemma also known as: Black & White Thinking. Giving two choices when in actuality there could be more choices possible.

Example of a False Dilemma Either scientists can explain the strange objects seen in the sky over Gulf Breeze, Florida, or these objects are piloted by visitors from outer space. Scientists cannot explain these objects, so they must be visitors from outer space. False Dilemma (black or white) What else could it be?

False Dilemma Involves a situation in which only two alternatives are given when there could be many more. It is a black or white situation (Fallacy comes in thinking there is no gray area) Example: Bill: "Jill and I both support having prayer in public schools." Jill: "Hey, I never said that!" Bill: "You're not an atheist are you Jill?"

False Analogy False Analogy Definition: In an analogy, two objects (or events), A and B are shown to be similar. Then it is argued that since A has property P, so also B must have property P. An analogy fails when the two objects, A and B, are different in a way which affects whether they both have property P. Examples: 1. Employees are like nails. Just as nails must be hit in the head in order to make them work, so must employees.

False Analogy False Analogy, non sequitur (doesn’t follow)

What is wrong with this thinking? False Analogy, non sequitur (doesn’t follow)

“A cloud is 90% water. A watermelon is 90% water “A cloud is 90% water. A watermelon is 90% water. Therefore, since a plane can fly through a cloud, a plane can fly through a watermelon.” Non sequitur (doesn’t follow) False Analogy

Non Sequitur Non Sequitur "It does not follow." arguments don’t follow a logical sequence. The conclusion doesn’t logically follow the explanation. These fallacies can be found on both the sentence level and the level of the argument itself. Examples:  1. We know why it rained today: because I washed my car.

False Authority False Authority – using a biased, suspicious, or incredible source to defend a conclusion. One of the best strategies a writer can employ to support his arguments is to tap into the authority of widely respected people, books, or institutions.  A false authority fallacy occurs when people offer themselves (or other suspicious authorities) as sufficient warrant for believing their claims. Kid: "Why can't I get a new video game?" Dad: "Because I said so."

Paris Hilton loves this perfume so it must smell “hot” Is Paris a profession perfume maker? Does she have a job in the “smell” business? False authority

Post Hoc Post Hoc also known as Post Hoc Ergo Propter Hoc. A Post Hoc is a fallacy with the following form: A occurs before B. Therefore A is the cause of B. This has been traditionally interpreted as "After this, therefore because of this." I had been doing pretty poorly this season. Then my girlfriend gave me this neon laces for my spikes and I won my next three races. Those laces must be good luck...if I keep on wearing them I can't help but win!

Straw Man occurs when an opponent takes the original argument of his/her adversary and then offers a close imitation, or straw man, version of the original argument; "knocks down" the straw man version of the argument (because the straw man, as its name implies, is a much easier target to hit, undermine, etc.) The author attacks an argument which is different from, and usually weaker than, the opposition's best argument. Exaggerating the opponents argument in order to make it easier to attack or refute. Man: "The statue of Venus De Milo has no arms." Woman: "So you're saying that women can't lift heavy objects!“

Kinds of Logical Fallacy 12th Begging the Question (petitio principii) a statement or claim is assumed to be true without evidence other than the statement or claim itself. Example: "I think he is unattractive because he is ugly.“

Red Herrings A dead fish whose funky smell distracts from everything else. Red Herrings are used in dog training to make sure the dog ignores all other scents except its original goal, when an irrelevant topic or point is brought up to distract from the real issue. Example I know your car isn't working right.  But, if you had gone to the store one day earlier, you'd not be having problems.

More Fallacies On your own, visit the links below to explore the vast universe of logical fallacies! http://sun-design.com/talitha/fallacies.html http://owl.english.purdue.edu/handouts/general/gl_fallacies.html www.datanation.com/fallacies/index.htm

Classroom Activities Logical fallacy roundup: in groups, search websites, newspapers, advertisements, etc. to find arguments that may contain logical fallacies. Present these to the class. Find two logical fallacies to share with the class

Activities, cont’d Using your list of fallacies, create examples of your own Write a short op/ed article that is based on one logical fallacy Write an argument using as many logical fallacies as you can Make a chart to tally logical fallacies that you hear in everyday conversation

Even more activities… Bring in visual examples of logical fallacies from advertisements, etc. Identify fallacies from in-class video screening Identify logical fallacies from editorial cartoons

In conclusion, always be on the lookout for faulty reasoning! If you understand this PowerPoint and completed some of the activities, you are a genius! (logical fallacy) Congratulations!