New Foundations Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > NFE Home > Th. List > ax-9d2 | GIF version |
Description: Distinct variable version of ax9 1949, distinct variables case. (Contributed by Mario Carneiro, 14-Aug-2015.) |
Ref | Expression |
---|---|
ax-9d2 | ⊢ ¬ ∀x ¬ x = y |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | vx | . . . . 5 setvar x | |
2 | vy | . . . . 5 setvar y | |
3 | 1, 2 | weq 1643 | . . . 4 wff x = y |
4 | 3 | wn 3 | . . 3 wff ¬ x = y |
5 | 4, 1 | wal 1540 | . 2 wff ∀x ¬ x = y |
6 | 5 | wn 3 | 1 wff ¬ ∀x ¬ x = y |
Colors of variables: wff setvar class |
This axiom is referenced by: (None) |
Copyright terms: Public domain | W3C validator |