theorem mpd (a b c: wff): $ a -> b $ > $ a -> b -> c $ > $ a -> c $;
| Step | Hyp | Ref | Expression |
|---|
| 1 |
|
ax_2 |
(a -> b -> c) -> (a -> b) -> a -> c |
| 2 |
|
hyp h2 |
a -> b -> c |
| 3 |
1, 2 |
ax_mp |
(a -> b) -> a -> c |
| 4 |
|
hyp h1 |
a -> b |
| 5 |
3, 4 |
ax_mp |
a -> c |
Axiom use
axs_prop_calc
(ax_2,
ax_mp)