Theorem bj-tagn0 34781

Description: The tagging of a class is nonempty. (Contributed by BJ, 6-Apr-2019.)

Assertion

Ref	Expression
bj-tagn0	⊢ tag 𝐴 ≠ ∅

Proof of Theorem bj-tagn0

Step	Hyp	Ref	Expression
1		bj-0eltag 34780	. 2 ⊢ ∅ ∈ tag 𝐴
2	1	ne0ii 4224	1 ⊢ tag 𝐴 ≠ ∅

Syntax hints:   ≠ wne 2934  ∅c0 4209  tag bj-ctag 34776

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1802  ax-4 1816  ax-5 1916  ax-6 1974  ax-7 2019  ax-8 2115  ax-9 2123  ax-ext 2710  ax-nul 5171

This theorem depends on definitions:  df-bi 210  df-an 400  df-or 847  df-tru 1545  df-fal 1555  df-ex 1787  df-sb 2074  df-clab 2717  df-cleq 2730  df-clel 2811  df-ne 2935  df-v 3399  df-dif 3844  df-un 3846  df-nul 4210  df-sn 4514  df-bj-tag 34777

This theorem is referenced by:  bj-1upln0  34811  bj-2upln1upl  34826