Description: Existential elimination rule of natural deduction. (Contributed by ML, 17-Jul-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | exlimimd.1 | ⊢ ( 𝜑 → ∃ 𝑥 𝜓 ) | |
| exlimimd.2 | ⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) ) | ||
| Assertion | exlimimd | ⊢ ( 𝜑 → 𝜒 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | exlimimd.1 | ⊢ ( 𝜑 → ∃ 𝑥 𝜓 ) | |
| 2 | exlimimd.2 | ⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) ) | |
| 3 | 2 | imp | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜒 ) |
| 4 | 1 3 | exlimddv | ⊢ ( 𝜑 → 𝜒 ) |