Description: The empty set is greater than any set of surreals. (Contributed by Scott Fenton, 8-Dec-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | nulssgt | |- ( A e. ~P No -> A <  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | id | |- ( A e. ~P No -> A e. ~P No )  | 
						|
| 2 | 0ex | |- (/) e. _V  | 
						|
| 3 | 2 | a1i | |- ( A e. ~P No -> (/) e. _V )  | 
						
| 4 | elpwi | |- ( A e. ~P No -> A C_ No )  | 
						|
| 5 | 0ss | |- (/) C_ No  | 
						|
| 6 | 5 | a1i | |- ( A e. ~P No -> (/) C_ No )  | 
						
| 7 | noel | |- -. y e. (/)  | 
						|
| 8 | 7 | pm2.21i | |- ( y e. (/) -> x  | 
						
| 9 | 8 | 3ad2ant3 | |- ( ( A e. ~P No /\ x e. A /\ y e. (/) ) -> x  | 
						
| 10 | 1 3 4 6 9 | ssltd | |- ( A e. ~P No -> A <  |