Number | Statement | Line(s) Used | Reason | |
1 | C --> (N & I) | |||
2 | (N v P) --> (I --> ~C) | |||
:. | ~C | |||
3 | ~(~C) | Assumption for Indirect Proof | ||
4 | C | 3 | Double Negation | |
5 | N & I | 1, 4 | Modus Ponens | |
6 | I & N | 5 | Commutation | |
7 | N | 5 | Simplification | |
8 | I | 6 | Simplification | |
9 | N v P | 7 | Addition | |
10 | I --> ~C | 2, 9 | Modus Ponens | |
11 | ~C | 10, 8 | Modus Ponens | |
12 | C & (~C) | 4, 11 | Conjunction | |
13 | ~C | 3 - 12 | Indirect Proof |