| New Foundations Explorer |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > NFE Home > Th. List > ax-10d | GIF version | ||
| Description: Distinct variable version of ax10 1944. (Contributed by Mario Carneiro, 14-Aug-2015.) |
| Ref | Expression |
|---|---|
| ax-10d | ⊢ (∀x x = y → ∀y y = x) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | vx | . . . 4 setvar x | |
| 2 | vy | . . . 4 setvar y | |
| 3 | 1, 2 | weq 1643 | . . 3 wff x = y |
| 4 | 3, 1 | wal 1540 | . 2 wff ∀x x = y |
| 5 | 2, 1 | weq 1643 | . . 3 wff y = x |
| 6 | 5, 2 | wal 1540 | . 2 wff ∀y y = x |
| 7 | 4, 6 | wi 4 | 1 wff (∀x x = y → ∀y y = x) |
| Colors of variables: wff setvar class |
| This axiom is referenced by: (None) |
| Copyright terms: Public domain | W3C validator |