Logical Fallacies

1. Logical Fallacies

2. A logical fallacy is a weak argument

3. Ad hominem • You attack the person rather than his or her statements • The phrase is Latin for “to the man”

4. Example • No wonder “Hills Like White Elephants” is an awful story: everyone knows Hemingway was an alcoholic.

5. Ad populum • You appeal to the audience’s devotion to country or family • The phrase is Latin for “to the people”

6. Example • North American cars are better than foreign cars because they are built right here by our own people.

7. Appeal to fear • You attempt to persuade by playing on the audience’s fears.

8. Example • If you allow this alleged murderer to go free, your own children will be in mortal danger.

9. Appeal to ignorance • You assert that since something has never been proven, it must not be true.

10. Example • Since we have never found evidence of life on Mars, there must not be any.

11. Appeal to pity • You attempt to persuade by substituting sympathy for logic.

12. Example • One look at these malnourished children should convince you to give all of your money to our charity.

13. Bandwagon • You assert that something is right or acceptable because everyone is doing it.

14. Example • Cheat on your taxes; everyone I know already does.

15. Begging the question • You present an opinion as a given fact

16. Example • Homeless people contribute nothing to society. They should be denied welfare. • (Do homeless people contribute nothing? Why should they be denied welfare?)

17. Complex question • Forces the audience to admit something that may not be true, because the question asked contains an unproven assumption

18. Example • Have you quit smoking? • (to say yes is to admit that you used to smoke; to say no is to admit you still smoke.) • The question is unfair if directed at someone who still smokes.

19. Enthymeme • Not a fallacy, but a common form of argument in which either one of the premises or the conclusion is missing • The phrase is Latin for “in the mind”

20. Example • Mowing the lawn is a waste of time, because the grass never stops growing anyway. • This argument overlooks that fact that regular mowing maintains an attractive lawn.

21. False dichotomy • You deny the possibility of more than two alternatives.

22. Example • There are two kinds of exams: bad and awful!

23. Hasty generalization: • You deny exceptions

24. Example • All police officers are unthinking bullies.

25. Non sequitur • The conclusion does not follow from the premises • Phrase is Latin for “it does not follow”

26. Example • All men are mortal • Gloria is not a man • Therefore Gloria is not mortal • (The mistake arises form the assumption that the first premise also means “Only men are mortal.”

27. Overgeneralization • The effects are attributed to actions that may not be the complete cause, or may not be the cause at all

28. Example • To get rid of crime, get rid of all the drug users.

30. Post hoc ergo propter hoc • An affect is attributed to an action simply because the action came first • Latin for “after this, therefore because of this.)

31. Example • The escalation of baseball players’ salaries is responsible for the recent melting of the polar ice caps.

32. Red Herring • You try to distract the audience from your argument by introducing something unrelated.

33. Example • Of course, that team’s owner is losing millions of dollars. However, the team has won four games in a row, and the owner would never sell the team while it is winning. • The winning streak is the red herring. If the owner loses enough money, he/she will sell the team regardless of its performance.)

34. Slanted language • You use the connotations of words to portray similarities as substantial differences.

35. Example • I am a strong conswervative, eager to protect the state and its people by limiting immigration and introducing racial segregation. My opponent, however, is a fascist.

36. Tautology • An argument that proves nothing since something is just defined in different terms ( also called a circular argument.)

37. Example • All unmarried men are bachelors. • Hanif is an unmarried man. • Therefore, Hanif is a bachelor. • ( Comment: Bachelorhood is the defining feature of unmarried men. It is not a quality such as mortality, greed, generosity, and so on.)

38. Testimonial • An expert in one field offers his or her opinion in another field.

39. Example: • We should all drive the new SUV because that Olympic winner drives one.

40. Undistributed Middle • Holds that because two agents perform some action, they share each other’s qualities. • Used a lot by advertisers.

41. Example • Successful people drive SUVs. If you drive an SUV, you will be a successful person.