Description: An ordinal number is an ordinal class. (Contributed by NM, 11-Jun-1994)
Ref | Expression | ||
---|---|---|---|
Hypothesis | on.1 | ⊢ 𝐴 ∈ On | |
Assertion | onordi | ⊢ Ord 𝐴 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | on.1 | ⊢ 𝐴 ∈ On | |
2 | eloni | ⊢ ( 𝐴 ∈ On → Ord 𝐴 ) | |
3 | 1 2 | ax-mp | ⊢ Ord 𝐴 |