Description: A deduction which "stacks" a hypothesis. (Contributed by Stanislas Polu, 9-Mar-2020) (Proof shortened by Wolf Lammen, 28-Mar-2021)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | mpidan.1 | |- ( ph -> ch ) | |
| mpidan.2 | |- ( ( ( ph /\ ps ) /\ ch ) -> th ) | ||
| Assertion | mpidan | |- ( ( ph /\ ps ) -> th ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | mpidan.1 | |- ( ph -> ch ) | |
| 2 | mpidan.2 | |- ( ( ( ph /\ ps ) /\ ch ) -> th ) | |
| 3 | 1 | adantr | |- ( ( ph /\ ps ) -> ch ) | 
| 4 | 3 2 | mpdan | |- ( ( ph /\ ps ) -> th ) |