Metamath Proof Explorer


Theorem anasss

Description: Associative law for conjunction applied to antecedent (eliminates syllogism). (Contributed by NM, 15-Nov-2002)

Ref Expression
Hypothesis anasss.1 φψχθ
Assertion anasss φψχθ

Proof

Step Hyp Ref Expression
1 anasss.1 φψχθ
2 1 exp31 φψχθ
3 2 imp32 φψχθ