Description: Elimination of a conjunct. Theorem *3.26 (Simp) of WhiteheadRussell p. 112. (Contributed by NM, 3-Jan-1993) (Proof shortened by Wolf Lammen, 14-Jun-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | simpl | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜑 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | id | ⊢ ( 𝜑 → 𝜑 ) | |
| 2 | 1 | adantr | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜑 ) |