Philosophy homework

Philosophy 117 CH 7: Validity and Truth Tables Glen Nesse

Directions: Create a truth table for the following arguments. Indicate the truth values for the variables that show us that the argument is invalid. (Hint: this will be the truth values that make every premise true and the conclusion false, informally called the counterexample row.) You may copy and paste the following symbols for your truth tables: Negation: ∼ Disjunction: ⌵ Conjunction: ⦁ Conditional: → Biconditional: ↔

(#1) 1. (P ⌵ P) ↔ P

2. ∴ ∼ P

(#2) 1. P ⌵ Q

2. ∴ P ⦁ Q

(#3)

1. A ⌵ B

2. A

3. ∴B

(#4)

1. (∼P ↔ ∼Q) → ∼R

2. P ⦁ Q

3. ∴R

(#5) 1. (R ⦁ T) ⌵ ~R

2. T ↔ Q

3. ∴ Q