Metamath Proof Explorer


Theorem thinccatd

Description: A thin category is a category (deduction form). (Contributed by Zhi Wang, 24-Sep-2024)

Ref Expression
Hypothesis thinccatd.c ⊢ φ → C ∈ ThinCat
Assertion thinccatd ⊢ φ → C ∈ Cat

Proof

Step Hyp Ref Expression
1 thinccatd.c ⊢ φ → C ∈ ThinCat
2 thinccat ⊢ C ∈ ThinCat → C ∈ Cat
3 1 2 syl ⊢ φ → C ∈ Cat