Theorem bj-tagn0 36945

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 36944	. 2 ⊢ ∅ ∈ tag 𝐴
2	1	ne0ii 4367	1 ⊢ tag 𝐴 ≠ ∅

Syntax hints:   ≠ wne 2946  ∅c0 4352  tag bj-ctag 36940

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1793  ax-4 1807  ax-5 1909  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-ext 2711  ax-nul 5324

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 847  df-tru 1540  df-fal 1550  df-ex 1778  df-sb 2065  df-clab 2718  df-cleq 2732  df-clel 2819  df-ne 2947  df-v 3490  df-dif 3979  df-un 3981  df-nul 4353  df-sn 4649  df-bj-tag 36941

This theorem is referenced by:  bj-1upln0  36975  bj-2upln1upl  36990