Description: A set belongs to its successor. (Contributed by NM, 22-Jun-1994) (Proof shortened by Alan Sare, 18-Feb-2012) (Proof shortened by Scott Fenton, 20-Feb-2012)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | sucid.1 | ⊢ 𝐴 ∈ V | |
| Assertion | sucid | ⊢ 𝐴 ∈ suc 𝐴 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | sucid.1 | ⊢ 𝐴 ∈ V | |
| 2 | sucidg | ⊢ ( 𝐴 ∈ V → 𝐴 ∈ suc 𝐴 ) | |
| 3 | 1 2 | ax-mp | ⊢ 𝐴 ∈ suc 𝐴 |