Description: Apply a choice equivalent. (Contributed by Mario Carneiro, 17-May-2015)
Ref | Expression | ||
---|---|---|---|
Hypothesis | axaci.1 | ⊢ ( CHOICE ↔ ∀ 𝑥 𝜑 ) | |
Assertion | axaci | ⊢ 𝜑 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | axaci.1 | ⊢ ( CHOICE ↔ ∀ 𝑥 𝜑 ) | |
2 | axac3 | ⊢ CHOICE | |
3 | 2 1 | mpbi | ⊢ ∀ 𝑥 𝜑 |
4 | 3 | spi | ⊢ 𝜑 |