Chapter 3: Reality Assumptions

1. Chapter 3: Reality Assumptions This chapter will cover • Reality assumptions • Patterns of deductive reasoning • Using deductive reasoning to test logic, discover truth, make decisions, avoid stereotyping, and understand argument.

2. Reality Assumptions • Based on unique experience of individual Beliefs about what is true and factual about the world.

3. Detecting Reality Assumptions Toulmin’s Model • Issue: Should we use the SAT or ACT scores to predict success in college?

4. Toulmin’s Model Reason Students will not likely succeed Warrant (Reality Assumption) Scores are accurate predictions of how well a student is prepared Claim - Students should not apply to colleges at which SAT scores are 200 points higher than theirs. Based on

5. Toulmin’s Model Claim Colleges should not use standardized test scores as a measure of success. Reason Test only predicts level of struggle for first year. Warrant (Reality Assumption) Students success based on character qualities that are not measured by the tests. Based on

6. Toulmin’s Model Issue:Should trials and executions be televised

7. Toulmin’s Model Claim: Trials and executions should be televised Warrant (Reality Assumption) Televising trials would inform the public about our judicial system. Warrant (Value Assumption) Freedom of information is an important value Reason: Public has the right to have more information about the courts and the judicial system. Based on

8. Reasoning Deductive Reasoning General statement to a specific instance

9. Reasoning Deductive Inductive Gives us Probabilities Specific to General Chapter 6 • Aims for Certainty General to Specific

10. Deductive Reasoning Syllogism- a classic example • All men are mortal. (major premise) • Socrates is a man.(minor premise) • Therefore, Socrates is mortal. (conclusion)

11. Deductive Reasoning Validity • Correct form makes an argument valid (logical). • Accurate content makes it true. • When the form is valid and the content is true, the argument is sound.

12. Deductive Reasoning is content true? All students eat pizza. Claire is a student at CSU. Is form valid? • Therefore, Claire eats pizza. Is it sound? No

13. Deductive Reasoning is content true? All women are terrible drivers. Jane is a woman. Is form valid? • Therefore, Jane is a terrible driver. Is it sound? Yes

14. Deductive Reasoning Pattern of Deductive reasoning All As are Bs. Categorical statement m is A. Therefore, m is B

15. Deductive Reasoning Categorical Statement All As are Bs. B A A statement in which members of one class are said to be included in Another class.

16. Conditional/hypothetical syllogism Modus ponens: ‘the way of affirmation’: the antecedent leads to the consequent. If A, then B A Therefore, B B A

17. Conditional/hypothetical syllogism If I have strep throat, then the culture will be positive. But the culture is not positive. So, I don’t have strep throat. ‘denying the consequent.’ If A, then B Not A Therefore not B Modus tollens: B A

18. Deductive Reasoning Questionable Premises All drivers who speed are subject to a fine. You are speeding. Which premise can be contested? • Therefore, you are subject to a fine.

19. Deductive Reasoning Enthymeme • Key part is implied rather than directly stated.

20. Deductive Reasoning Sound Argument: Correct Form True Premises Unsound Argument: Correct Form Untrue Premises Unsound Argument: Incorrect Form, Untrue Premises True False Unsound Argument: Incorrect Form, True Premises Valid Invalid

21. Deductive Reasoning Deductive reasoning can: • Uncover Reality Assumptions • Discover Truth and Make Decisions • Combat Prejudice and Stereotyping

22. Skill A critical thinker uses reasoning to discover truth and prevent stereotyping

23. Chapter 3: Reality Assumptions Checkup • Reality versus value assumptions • Validity in an argument • What makes a deductive argument sound • What does deductive reasoning aim to establish