Users' Mathboxes Mathbox for David A. Wheeler < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >   Mathboxes  >  alsi1d GIF version

Theorem alsi1d 13957
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.)
Hypothesis
Ref Expression
alsi1d.1 (𝜑 → ∀!𝑥(𝜓𝜒))
Assertion
Ref Expression
alsi1d (𝜑 → ∀𝑥(𝜓𝜒))

Proof of Theorem alsi1d
StepHypRef Expression
1 alsi1d.1 . . 3 (𝜑 → ∀!𝑥(𝜓𝜒))
2 df-alsi 13954 . . 3 (∀!𝑥(𝜓𝜒) ↔ (∀𝑥(𝜓𝜒) ∧ ∃𝑥𝜓))
31, 2sylib 121 . 2 (𝜑 → (∀𝑥(𝜓𝜒) ∧ ∃𝑥𝜓))
43simpld 111 1 (𝜑 → ∀𝑥(𝜓𝜒))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 103  wal 1341  wex 1480  ∀!walsi 13952
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105
This theorem depends on definitions:  df-bi 116  df-alsi 13954
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator