theorem isf0: $ isfun 0 $;
| Step | Hyp | Ref | Expression |
|---|
| 1 |
|
absurd |
~x, y e. 0 -> x, y e. 0 -> x, z e. 0 -> y = z |
| 2 |
|
el02 |
~x, y e. 0 |
| 3 |
1, 2 |
ax_mp |
x, y e. 0 -> x, z e. 0 -> y = z |
| 4 |
3 |
ax_gen |
A. z (x, y e. 0 -> x, z e. 0 -> y = z) |
| 5 |
4 |
ax_gen |
A. y A. z (x, y e. 0 -> x, z e. 0 -> y = z) |
| 6 |
5 |
ax_gen |
A. x A. y A. z (x, y e. 0 -> x, z e. 0 -> y = z) |
| 7 |
6 |
conv isfun |
isfun 0 |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_3,
ax_mp,
itru),
axs_pred_calc
(ax_gen,
ax_4,
ax_5,
ax_6,
ax_7,
ax_10,
ax_11,
ax_12),
axs_set
(elab,
ax_8),
axs_the
(theid,
the0),
axs_peano
(peano1,
peano2,
peano5,
addeq,
muleq,
add0,
addS,
mul0,
mulS)