Examine whether the following statement pattern is a tautology, a contradiction or a contingency.
~ p → (p → ~ q)
SOLUTION
| p | q | ~p | ~q | p→~q | ~p→(p→~q) |
| T | T | F | F | F | T |
| T | F | F | T | T | T |
| F | T | T | F | T | T |
| F | F | T | T | T | T |
All the truth values in the last column are T. Hence, it is tautology.
