Description: Membership in a predecessor class - implicative version. (Contributed by Scott Fenton, 9-May-2012) (Proof shortened by BJ, 16-Oct-2024)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | elpredim.1 | ⊢ 𝑋 ∈ V | |
| Assertion | elpredim | ⊢ ( 𝑌 ∈ Pred ( 𝑅 , 𝐴 , 𝑋 ) → 𝑌 𝑅 𝑋 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elpredim.1 | ⊢ 𝑋 ∈ V | |
| 2 | elpredimg | ⊢ ( ( 𝑋 ∈ V ∧ 𝑌 ∈ Pred ( 𝑅 , 𝐴 , 𝑋 ) ) → 𝑌 𝑅 𝑋 ) | |
| 3 | 1 2 | mpan | ⊢ ( 𝑌 ∈ Pred ( 𝑅 , 𝐴 , 𝑋 ) → 𝑌 𝑅 𝑋 ) |