MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  nfe1OLD Structured version   Visualization version   GIF version

Theorem nfe1OLD 2020
Description: Obsolete proof of nfe1 2014 as of 6-Oct-2021. (Contributed by Mario Carneiro, 11-Aug-2016.) (Proof modification is discouraged.) (New usage is discouraged.)
Assertion
Ref Expression
nfe1OLD 𝑥𝑥𝜑

Proof of Theorem nfe1OLD
StepHypRef Expression
1 hbe1 2008 . 2 (∃𝑥𝜑 → ∀𝑥𝑥𝜑)
21nfiOLD 1725 1 𝑥𝑥𝜑
Colors of variables: wff setvar class
Syntax hints:  wex 1695  wnfOLD 1700
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-10 2006
This theorem depends on definitions:  df-bi 196  df-ex 1696  df-nfOLD 1712
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator