| Step | Hyp | Ref | Expression | 
						
							| 1 |  | zrinitorngc.u | ⊢ ( 𝜑  →  𝑈  ∈  𝑉 ) | 
						
							| 2 |  | zrinitorngc.c | ⊢ 𝐶  =  ( RngCat ‘ 𝑈 ) | 
						
							| 3 |  | zrinitorngc.z | ⊢ ( 𝜑  →  𝑍  ∈  ( Ring  ∖  NzRing ) ) | 
						
							| 4 |  | zrinitorngc.e | ⊢ ( 𝜑  →  𝑍  ∈  𝑈 ) | 
						
							| 5 | 1 2 3 4 | zrinitorngc | ⊢ ( 𝜑  →  𝑍  ∈  ( InitO ‘ 𝐶 ) ) | 
						
							| 6 | 1 2 3 4 | zrtermorngc | ⊢ ( 𝜑  →  𝑍  ∈  ( TermO ‘ 𝐶 ) ) | 
						
							| 7 |  | eqid | ⊢ ( Base ‘ 𝐶 )  =  ( Base ‘ 𝐶 ) | 
						
							| 8 |  | eqid | ⊢ ( Hom  ‘ 𝐶 )  =  ( Hom  ‘ 𝐶 ) | 
						
							| 9 | 2 | rngccat | ⊢ ( 𝑈  ∈  𝑉  →  𝐶  ∈  Cat ) | 
						
							| 10 | 1 9 | syl | ⊢ ( 𝜑  →  𝐶  ∈  Cat ) | 
						
							| 11 | 3 | eldifad | ⊢ ( 𝜑  →  𝑍  ∈  Ring ) | 
						
							| 12 |  | ringrng | ⊢ ( 𝑍  ∈  Ring  →  𝑍  ∈  Rng ) | 
						
							| 13 | 11 12 | syl | ⊢ ( 𝜑  →  𝑍  ∈  Rng ) | 
						
							| 14 | 4 13 | elind | ⊢ ( 𝜑  →  𝑍  ∈  ( 𝑈  ∩  Rng ) ) | 
						
							| 15 | 2 7 1 | rngcbas | ⊢ ( 𝜑  →  ( Base ‘ 𝐶 )  =  ( 𝑈  ∩  Rng ) ) | 
						
							| 16 | 14 15 | eleqtrrd | ⊢ ( 𝜑  →  𝑍  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 17 | 7 8 10 16 | iszeroo | ⊢ ( 𝜑  →  ( 𝑍  ∈  ( ZeroO ‘ 𝐶 )  ↔  ( 𝑍  ∈  ( InitO ‘ 𝐶 )  ∧  𝑍  ∈  ( TermO ‘ 𝐶 ) ) ) ) | 
						
							| 18 | 5 6 17 | mpbir2and | ⊢ ( 𝜑  →  𝑍  ∈  ( ZeroO ‘ 𝐶 ) ) |