Logical Fallacies

1. Logical Fallacies Introduction and Activities

2. 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

3. Origins • The word “fallacy” may derive from the Latin word fallere meaning, “to deceive, to trip, to lead into error or to trick.”

4. 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)

5. Types of Logical Fallacies The following slides will briefly explain various fallacies. Please keep in mind there are many kinds of fallacies. 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

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

7. Types of Logical Fallacies • “Slippery Slope” • This is a conclusion based on the premise that if one thing happens, then something else will, too. “If you don’t stop smoking cigarettes, then you are going to start shooting heroin.”

8. Types of Logical Fallacies Circular Argument: This restates the argument rather than actually proving it. “Obama is a good communicator because he speaks effectively.”

9. Types of Logical Fallacies Straw Man: This move oversimplifies an opponent's viewpoint and then attacks that hollow argument. “People who don't support the proposed state minimum wage increase hate the poor.”

10. Types of Logical Fallacies Ad hominem: This is an attack on the character of a person rather than her/his opinions or arguments. “Green Peace's strategies aren't effective because they are all dirty, lazy hippies.”

11. Types of Logical Fallacies Red Herring: This is a diversionary tactic that avoids the key issues, often by avoiding opposing arguments rather than addressing them. “The level of mercury in seafood may be unsafe, but what will fishers do to support their families?”

12. 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

13. Classroom Activities (Using a printout of the Owl fallacy list) • 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

14. 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

15. 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

16. In conclusion, always be on the lookout for faulty reasoning! If you read this PowerPoint and completed some of the activities, you are a genius! Congratulations!