Description: An inference based on modus ponens. (Contributed by NM, 23-May-1999) (Proof shortened by Wolf Lammen, 22-Nov-2012)
Ref | Expression | ||
---|---|---|---|
Hypotheses | mpdan.1 | ⊢ ( 𝜑 → 𝜓 ) | |
mpdan.2 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜒 ) | ||
Assertion | mpdan | ⊢ ( 𝜑 → 𝜒 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mpdan.1 | ⊢ ( 𝜑 → 𝜓 ) | |
2 | mpdan.2 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜒 ) | |
3 | id | ⊢ ( 𝜑 → 𝜑 ) | |
4 | 3 1 2 | syl2anc | ⊢ ( 𝜑 → 𝜒 ) |