1. For Friday, read Chapter 2, section 5. As nongraded homework, do the problems at the end of the section. I sent out graded HW#2 yesterday. It’s due on Friday at the beginning of class. Exam #1 will be given one week from Friday. It covers Chapters 1 and 2 (except for chapter 2, section 6).

2. If she’s invited, Tammy will come to the party. I → P Tammy will come to the party only if she’s invited. (This is taken to mean that she won’t come if she’s not invited.) P → I

3. Also, sufficient condition = antecedent, necessary condition = consequent If you’re a human, then you’re a mammal. (H: You’re a human; M: You’re a mammal) Sufficient → necessary H → M but if someone says that being a mammal is sufficient for being a human, then write M → H, even though the statement is false.

4. ‘Whenever’ and ‘unless’ Whenever Terry lectures, she uses slides. (L: Terry lectures; S: Terry uses slides) L → S Tom will not graduate unless he fulfills all of the course requirements. (G: Tom graduates; F: Tom fulfills all of the course requirements) ~ F → ~ G

5. ‘↔’ is the double-arrow; it abbreviates ‘if and only if’ and equivalent phrases (such as ‘just in case’) Martha is brilliant if and only if she is a genius. (B: Martha is brilliant; G: Martha is a genius) B ↔ G

6. 3. Parentheses are used for grouping. Either Tom is a doctor or Jill is a doctor, but not both. (T: Tom is a doctor; J: Jill is a doctor) (T v J) & ~ (T & J) This expresses the exclusive ‘or’, by the way.

7. Tips for grouping in longer translations: 1. Use punctuation as a guide; the stronger the form of punctuation, the larger the scope of the operator in the corresponding position. Pat is happy, or Tom is happy; but both of them are rich. (P: Pat is happy; T: Tom is happy; R: Pat is rich; H: Tom is rich). (P v T) & ( R & H)

8. 2. Consider the relative positions of logical terms (e.g., ‘either’, ‘or’, ‘if’, ‘then’ and ‘both’). Either Jim will graduate and his wife will be promoted or he’ll be sad. (G: Jim will graduate; P: Jim’s wife will be promoted; S: Jim will be sad) (G & P) v S

9. 3. Compound subjects and predicates indicate grouping. Terry and Pat are from Russia or Tracy is from Ghana. (T: Terry is from Russia; P: Pat is from Russia; G: Tracy is from Ghana) (T & P) v G

10. Symbolizing Complete Arguments An argument: After I get my B.A., I’ll either go to law school, medical school, or business school. I hear that law school is a grind, and med school takes forever. An MBA it is, then. First determine the conclusion: B: I’m getting an MBA (or I’m going to business school; treat these as equivalent).