Description: A single axiom for propositional calculus discovered by Mordchaj Wajsberg (Logical Works, Polish Academy of Sciences, 1977). See: Fitelson,Some recent results in algebra and logical calculi obtained using automated reasoning, 2003 (axiom W on slide 8). (Contributed by Anthony Hart, 13-Aug-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | waj-ax | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nannan | |
|
2 | simpr | |
|
3 | 2 | imim2i | |
4 | pm2.27 | |
|
5 | 4 | anim2d | |
6 | 5 | expdimp | |
7 | 3 6 | syl5com | |
8 | 7 | con3d | |
9 | df-nan | |
|
10 | df-nan | |
|
11 | 8 9 10 | 3imtr4g | |
12 | nanim | |
|
13 | 11 12 | sylib | |
14 | pm3.21 | |
|
15 | 14 | adantr | |
16 | 15 | com12 | |
17 | 16 | a2i | |
18 | nannan | |
|
19 | 17 18 | sylibr | |
20 | 13 19 | jca | |
21 | 1 20 | sylbi | |
22 | nannan | |
|
23 | 21 22 | mpbir | |