Theorem bj-tagn0 33809

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 33808	. 2 ⊢ ∅ ∈ tag 𝐴
2	1	ne0ii 4191	1 ⊢ tag 𝐴 ≠ ∅

Syntax hints:   ≠ wne 2967  ∅c0 4180  tag bj-ctag 33804

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1758  ax-4 1772  ax-5 1869  ax-6 1928  ax-7 1965  ax-8 2052  ax-9 2059  ax-10 2079  ax-11 2093  ax-12 2106  ax-ext 2750  ax-nul 5068

This theorem depends on definitions:  df-bi 199  df-an 388  df-or 834  df-tru 1510  df-ex 1743  df-nf 1747  df-sb 2016  df-clab 2759  df-cleq 2771  df-clel 2846  df-nfc 2918  df-ne 2968  df-v 3417  df-dif 3834  df-un 3836  df-nul 4181  df-sn 4443  df-bj-tag 33805

This theorem is referenced by:  bj-1upln0  33839  bj-2upln1upl  33854