Description: If a class is a member of another class, then it is a set. Deduction associated with elex . (Contributed by Glauco Siliprandi, 11-Oct-2020)
Ref | Expression | ||
---|---|---|---|
Hypothesis | elexd.1 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
Assertion | elexd | ⊢ ( 𝜑 → 𝐴 ∈ V ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elexd.1 | ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 ) | |
2 | elex | ⊢ ( 𝐴 ∈ 𝑉 → 𝐴 ∈ V ) | |
3 | 1 2 | syl | ⊢ ( 𝜑 → 𝐴 ∈ V ) |