Metamath Proof Explorer


Theorem als1d

Description: Deduction rule: Given "all some" applied to a top-level inference, you can extract the "for all" part. (Contributed by David A. Wheeler, 20-Oct-2018)

Ref Expression
Hypothesis als1d.1 No typesetting found for |- ( ph -> AE x ( ps -> ch ) ) with typecode |-
Assertion als1d φ x ψ χ

Proof

Step Hyp Ref Expression
1 als1d.1 Could not format ( ph -> AE x ( ps -> ch ) ) : No typesetting found for |- ( ph -> AE x ( ps -> ch ) ) with typecode |-
2 df-als Could not format ( AE x ( ps -> ch ) <-> ( A. x ( ps -> ch ) /\ E. x ps ) ) : No typesetting found for |- ( AE x ( ps -> ch ) <-> ( A. x ( ps -> ch ) /\ E. x ps ) ) with typecode |-
3 1 2 sylib φ x ψ χ x ψ
4 3 simpld φ x ψ χ