Theorem bj-tagn0 37643

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 37642	. 2 ⊢ ∅ ∈ tag 𝐴
2	1	ne0ii 4296	1 ⊢ tag 𝐴 ≠ ∅

This proof depends on syntax axioms:   ≠ wne 2957  ∅c0 4285  tag bj-ctag 37638

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-8 2144  ax-9 2152  ax-ext 2734  ax-nul 5268

This proof depends on definitions:  df-bi 210  df-an 401  df-or 861  df-tru 1572  df-fal 1582  df-ex 1809  df-sb 2096  df-clab 2741  df-cleq 2754  df-clel 2837  df-ne 2958  df-v 3456  df-dif 3907  df-un 3909  df-nul 4286  df-sn 4589  df-bj-tag 37639

This theorem is used by:  bj-1upln0  37673  bj-2upln1upl  37688