theorem iald {x: nat} (a: wff) (b: wff x): $ a -> b $ > $ a -> A. x b $;
| Step | Hyp | Ref | Expression |
|---|
| 1 |
|
hyp h |
a -> b |
| 2 |
1 |
alimi |
A. x a -> A. x b |
| 3 |
|
ax_5 |
a -> A. x a |
| 4 |
2, 3 |
syl |
a -> A. x b |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_mp),
axs_pred_calc
(ax_gen,
ax_4,
ax_5)