Description: Surreal zero is a surreal. (Contributed by Scott Fenton, 7-Aug-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 0sno | |- 0s e. No  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-0s | |- 0s = ( (/) |s (/) )  | 
						|
| 2 | 0elpw | |- (/) e. ~P No  | 
						|
| 3 | nulssgt | |- ( (/) e. ~P No -> (/) <  | 
						|
| 4 | 2 3 | ax-mp | |- (/) <  | 
						
| 5 | scutcl | |- ( (/) <  | 
						|
| 6 | 4 5 | ax-mp | |- ( (/) |s (/) ) e. No  | 
						
| 7 | 1 6 | eqeltri | |- 0s e. No  |