Metamath Proof Explorer


Theorem 0thinc

Description: The empty category (see 0cat ) is thin. (Contributed by Zhi Wang, 17-Sep-2024)

Ref Expression
Assertion 0thinc ∅ ∈ ThinCat

Proof

Step Hyp Ref Expression
1 0ex ∅ ∈ V
2 base0 ∅ = ( Base ‘ ∅ )
3 0thincg ( ( ∅ ∈ V ∧ ∅ = ( Base ‘ ∅ ) ) → ∅ ∈ ThinCat )
4 1 2 3 mp2an ∅ ∈ ThinCat