Theorem bj-tagn0 37023

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 37022	. 2 ⊢ ∅ ∈ tag 𝐴
2	1	ne0ii 4291	1 ⊢ tag 𝐴 ≠ ∅

Syntax hints:   ≠ wne 2928  ∅c0 4280  tag bj-ctag 37018

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2113  ax-9 2121  ax-ext 2703  ax-nul 5242

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1544  df-fal 1554  df-ex 1781  df-sb 2068  df-clab 2710  df-cleq 2723  df-clel 2806  df-ne 2929  df-v 3438  df-dif 3900  df-un 3902  df-nul 4281  df-sn 4574  df-bj-tag 37019

This theorem is referenced by:  bj-1upln0  37053  bj-2upln1upl  37068