1 / 68

Argument in ordinary life: Change minds; influence people

Last week. Argument in ordinary life: Change minds; influence people. Beliefs you already have. Premises. (= Assumptions). Beliefs I want you to have. Conclusion. Philosophy is like ordinary life: U sing arguments to change minds. Philosophy is like ordinary life:

elata
Download Presentation

Argument in ordinary life: Change minds; influence people

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Last week Argument in ordinary life: Change minds; influence people Beliefs you already have Premises (= Assumptions) Beliefs I want you to have Conclusion

  2. Philosophy is like ordinary life: Using arguments to change minds.

  3. Philosophy is like ordinary life: Using arguments to change minds. Philosophy is not like ordinary life: Using arguments for theoretical activity.

  4. Theoretical Activity Asking just to know—without worrying about how answers can be used or applied.

  5. Theoretical Activity Asking just to know—without worrying about how answers can be used or applied. Doesn’t mean theories have no application, just that we aren’t thinking about applications while theorizing.

  6. Theoretical Activity Asking just to know—without worrying about how answers can be used or applied. Doesn’t mean theories have no application, just that we aren’t thinking about applications while theorizing. Without theoretical activity, we wouldn’t have electricity (for example).

  7. When you’re asking just to know, there’s no need for rhetoric.

  8. When you’re asking just to know, there’s no need for rhetoric. Rhetoric is “tricky” persuasion: trying to convince people of things whether or not they’re really true. (e.g., by appealing to emotion).

  9. When you’re asking just to know, there’s no need for rhetoric. Rhetoric is “tricky” persuasion: trying to convince people of things whether or not they’re really true. (e.g., by appealing to emotion). “Michael Jackson didn’t do anything wrong. He’s the greatest singer ever!”

  10. Premises:1) Michael Jackson is the greatest singer ever. Conclusion:Michael Jackson didn’t do anything wrong.

  11. Premises:1) Michael Jackson is the greatest singer ever. Assumption: 2) If Michael Jackson is a great singer, then he wouldn’t do things that are wrong. Conclusion:Michael Jackson didn’t do anything wrong.

  12. Premises:1) Michael Jackson is the greatest singer ever. Assumption: 2) If Michael Jackson is a great singer, then he wouldn’t do things that are wrong. ? Conclusion:Michael Jackson didn’t do anything wrong.

  13. Premises:1) Michael Jackson is the greatest singer ever. Assumption: 2) If Michael Jackson is a great singer, then he wouldn’t do things that are wrong. ? Conclusion:Michael Jackson didn’t do anything wrong. 1a) Great singers make people happy. 2a) People who make people happy don’t do things that are wrong. Ca) If MJ is a great singer, then he wouldn’t do things that are wrong.

  14. Premises:1) Michael Jackson is the greatest singer ever. Assumption: 2) If Michael Jackson is a great singer, then he wouldn’t do things that are wrong. ? Conclusion:Michael Jackson didn’t do anything wrong. 1a) Great singers make people happy. X 2a) People who make people happy don’t do things that are wrong. Ca) If MJ is a great singer, then he wouldn’t do things that are wrong.

  15. Rhetorical arguments “pull the wool over the eyes” of the audience.

  16. Rhetorical arguments “pull the wool over the eyes” of the audience. Useful in practical activities... -advertising -politics -law

  17. Rhetorical arguments “pull the wool over the eyes” of the audience. Useful in practical activities... -advertising -politics -law But not theoretical activities. If you’re asking just to know, you don’t want to trick yourself.

  18. Three Types of Argument Last week I asked: “What connects the premises with the conclusion?”

  19. ? Beliefs you already have Beliefs I want you to have

  20. ? Beliefs you already have Logic. Beliefs I want you to have

  21. ? Beliefs you already have Logic. Beliefs I want you to have Well, I lied—sort of...

  22. ? Beliefs you already have Logic. Beliefs I want you to have There are actually3 ways for premises to be “attached” to conclusions.

  23. Deductive argument Logic Beliefs you already have Inductive Argument Generalization Beliefs I want you to have Abductive Argument Explanation There are actually3 ways for premises to be “attached” to conclusions.

  24. Three Types of Argument Deductive If premises are true, conclusion must be true Inductive If premises are true, conclusion is probably true Abductive(different) The conclusion explains the premises.

  25. Deductive Arguments

  26. Deductive Arguments The Ideal: Logically valid All premises true

  27. Deductive Arguments The Ideal: Logically valid All premises true Real Life: Logically valid All premises agreed upon between arguer and audience

  28. Deductive Arguments Validity Truth

  29. Deductive Arguments Validity Truth Both of these are valid: All fish swim All sharks are fish All sharks swim

  30. Deductive Arguments Validity Truth Both of these are valid: All fish swim All sharks are fish All sharks swim All fish wear gold chains All sharks are fish All sharks wear gold chains

  31. Deductive Arguments Validity Truth Both of these are valid: All fish swim All sharks are fish All sharks swim All fish wear gold chains All sharks are fish All sharks wear gold chains

  32. Deductive Arguments Validity Truth An argument can be invalid even when every statement in it is true. All fish swim All sharks are fish All pimps wear gold chains

  33. Deductive Arguments Validity Truth Valid or Invalid -Arguments -Inferences True or False -Premises -Assumptions -Claims -Beliefs -Ideas -Sentences

  34. Deductive Arguments Quick Quiz: Last week I said that if an argument makes assumptions, the assumptions are necessary parts of the argument. Why are they necessary? A) Without them, the premises won’t be valid. B) Without them, the conclusion won’t be true. C) Without them, the argument won’t be true. D) Without them, the argument won’t be valid.

  35. Deductive Arguments Begging the Question (p. 19): God exists because the bible says so 2) Consumer Reports is reliable because it rates itself as reliable.

  36. Deductive Arguments Begging the Question (p. 19): God exists because the bible says so 2) Consumer Reports is reliable because it rates itself as reliable. Write out premises and conclusion. What’s the technical meaning of “circular reasoning”?

  37. Inductive Arguments

  38. Inductive Arguments If the premises are true, then the conclusion is probably true.

  39. Inductive Arguments Deductive inferences follow logically If Tim is taller than Andy and Andy is taller than Bill, it’s impossible for Bill to be taller than Andy.

  40. Inductive Arguments Deductive inferences follow logically If Tim is taller than Andy and Andy is taller than Bill, it’s impossible for Bill to be taller than Andy. Inductive inferences don’t

  41. Inductive Arguments Deductive inferences follow logically If Tim is taller than Andy and Andy is taller than Bill, it’s impossible for Bill to be taller than Andy. Inductive inferences don’t If a woman isn’t wearing a wedding ring, it’s still possible that she’s married.

  42. Inductive Arguments Induction = Generalization Essential to science: If this salt dissolves in water, then all salt dissolves in water. Inferences about the world in general are drawn from a particular sample.

  43. Inductive Arguments Mathematical claims are verified by deduction... “2 + 2 = 4” Scientific claims are verified by induction. “Kangaroos don’t lay eggs.”

  44. Inductive Arguments Deductive inferences are either valid or not—validity doesn’t come in degrees. Inductive inferences do come in degrees—some generalizations are stronger than others.

  45. Inductive Arguments Inductive Strength 1) Sample Size 2) Bias (is sample representative?)

  46. Abductive Arguments The conclusion explainsthe premises. “Inference to the Best Explanation”

  47. Abductive Arguments The conclusion explainsthe premises. “Inference to the Best Explanation” ‘Inference’ is better than ‘argument.’ You can state an inference as an argument, but it’s less useful.

  48. Abductive Arguments The conclusion explainsthe premises. Mendel’s inference: Genes explain patterns of inheritance in pea plants.

  49. Abductive Arguments The conclusion explainsthe premises. Mendel’s inference: Genes explain patterns of inheritance in pea plants. Not an inference about genes in general drawn from observations of particular genes.

  50. Abductive Arguments The conclusion explainsthe premises. Mendel’s inference: Genes explain patterns of inheritance in pea plants. Not an inference about genes in general drawn from observations of particular genes. Mendel never observed a gene.

More Related