| Step | Hyp | Ref | Expression | 
						
							| 1 |  | initoeu1.c | ⊢ ( 𝜑  →  𝐶  ∈  Cat ) | 
						
							| 2 |  | initoeu1.a | ⊢ ( 𝜑  →  𝐴  ∈  ( InitO ‘ 𝐶 ) ) | 
						
							| 3 |  | initoeu2.i | ⊢ ( 𝜑  →  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 ) | 
						
							| 4 |  | ciclcl | ⊢ ( ( 𝐶  ∈  Cat  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐴  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 5 | 1 4 | sylan | ⊢ ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐴  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 6 |  | cicrcl | ⊢ ( ( 𝐶  ∈  Cat  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 7 | 1 6 | sylan | ⊢ ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 8 | 1 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐶  ∈  Cat ) | 
						
							| 9 |  | cicsym | ⊢ ( ( 𝐶  ∈  Cat  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐵 (  ≃𝑐  ‘ 𝐶 ) 𝐴 ) | 
						
							| 10 | 8 9 | sylan | ⊢ ( ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐵 (  ≃𝑐  ‘ 𝐶 ) 𝐴 ) | 
						
							| 11 |  | eqid | ⊢ ( Iso ‘ 𝐶 )  =  ( Iso ‘ 𝐶 ) | 
						
							| 12 |  | eqid | ⊢ ( Base ‘ 𝐶 )  =  ( Base ‘ 𝐶 ) | 
						
							| 13 |  | simprr | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 14 |  | simprl | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐴  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 15 | 11 12 8 13 14 | cic | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝐵 (  ≃𝑐  ‘ 𝐶 ) 𝐴  ↔  ∃ 𝑘 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) ) ) | 
						
							| 16 |  | eqid | ⊢ ( Hom  ‘ 𝐶 )  =  ( Hom  ‘ 𝐶 ) | 
						
							| 17 | 12 16 1 | isinitoi | ⊢ ( ( 𝜑  ∧  𝐴  ∈  ( InitO ‘ 𝐶 ) )  →  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 ) ) ) | 
						
							| 18 | 2 17 | mpdan | ⊢ ( 𝜑  →  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 ) ) ) | 
						
							| 19 |  | oveq2 | ⊢ ( 𝑎  =  𝑏  →  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 )  =  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 20 | 19 | eleq2d | ⊢ ( 𝑎  =  𝑏  →  ( 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 )  ↔  𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 21 | 20 | eubidv | ⊢ ( 𝑎  =  𝑏  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 )  ↔  ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 22 | 21 | rspcva | ⊢ ( ( 𝑏  ∈  ( Base ‘ 𝐶 )  ∧  ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 ) )  →  ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 23 |  | nfv | ⊢ Ⅎ ℎ 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) | 
						
							| 24 |  | nfv | ⊢ Ⅎ 𝑓 ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) | 
						
							| 25 |  | eleq1w | ⊢ ( 𝑓  =  ℎ  →  ( 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  ↔  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 26 | 23 24 25 | cbveuw | ⊢ ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  ↔  ∃! ℎ ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 27 |  | euex | ⊢ ( ∃! ℎ ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃ ℎ ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 28 | 1 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐶  ∈  Cat ) | 
						
							| 29 |  | simpr | ⊢ ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 30 | 29 | ad2antrl | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 31 |  | simprll | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐴  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 32 | 12 16 11 28 30 31 | isohom | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  ⊆  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 ) ) | 
						
							| 33 | 32 | sselda | ⊢ ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  →  𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 ) ) | 
						
							| 34 |  | eqid | ⊢ ( comp ‘ 𝐶 )  =  ( comp ‘ 𝐶 ) | 
						
							| 35 | 28 | ad2antrr | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  𝐶  ∈  Cat ) | 
						
							| 36 | 30 | ad2antrr | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 37 | 31 | ad2antrr | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  𝐴  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 38 |  | simprr | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  𝑏  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 39 | 38 | ad2antrr | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  𝑏  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 40 |  | simprl | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 ) ) | 
						
							| 41 |  | simprr | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 42 | 12 16 34 35 36 37 39 40 41 | catcocl | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 43 |  | simp-4l | ⊢ ( ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  𝜑 ) | 
						
							| 44 |  | df-3an | ⊢ ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) )  ↔  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) ) | 
						
							| 45 | 44 | biimpri | ⊢ ( ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) ) | 
						
							| 46 | 45 | ad4antlr | ⊢ ( ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) ) | 
						
							| 47 |  | simpr | ⊢ ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  →  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) ) | 
						
							| 48 | 47 | ad2antrr | ⊢ ( ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) ) | 
						
							| 49 | 41 | adantr | ⊢ ( ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 50 |  | simpr | ⊢ ( ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 51 | 1 2 12 16 11 34 | initoeu2lem2 | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 52 | 43 46 48 49 50 51 | syl113anc | ⊢ ( ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  ∧  ( ℎ ( 〈 𝐵 ,  𝐴 〉 ( comp ‘ 𝐶 ) 𝑏 ) 𝑘 )  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 53 | 42 52 | mpdan | ⊢ ( ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  ∧  ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) ) )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 54 | 53 | ex | ⊢ ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  →  ( ( 𝑘  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝐴 )  ∧  ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 ) )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) | 
						
							| 55 | 33 54 | mpand | ⊢ ( ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 ) )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) | 
						
							| 56 | 55 | ex | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) | 
						
							| 57 | 56 | com23 | ⊢ ( ( 𝜑  ∧  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) ) )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) | 
						
							| 58 | 57 | ex | ⊢ ( 𝜑  →  ( ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 59 | 58 | com15 | ⊢ ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  ∧  𝑏  ∈  ( Base ‘ 𝐶 ) )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 60 | 59 | expd | ⊢ ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) ) | 
						
							| 61 | 60 | com24 | ⊢ ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) ) | 
						
							| 62 | 61 | com12 | ⊢ ( ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) ) | 
						
							| 63 | 62 | exlimiv | ⊢ ( ∃ ℎ ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) ) | 
						
							| 64 | 27 63 | syl | ⊢ ( ∃! ℎ ℎ  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) ) | 
						
							| 65 | 26 64 | sylbi | ⊢ ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) ) | 
						
							| 66 | 65 | pm2.43i | ⊢ ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 67 | 66 | com12 | ⊢ ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 68 | 67 | adantr | ⊢ ( ( 𝑏  ∈  ( Base ‘ 𝐶 )  ∧  ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 ) )  →  ( ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑏 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 69 | 22 68 | mpd | ⊢ ( ( 𝑏  ∈  ( Base ‘ 𝐶 )  ∧  ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 ) )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) | 
						
							| 70 | 69 | ex | ⊢ ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ( ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝜑  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 71 | 70 | com15 | ⊢ ( 𝜑  →  ( ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 72 | 71 | adantld | ⊢ ( 𝜑  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  ∀ 𝑎  ∈  ( Base ‘ 𝐶 ) ∃! 𝑓 𝑓  ∈  ( 𝐴 ( Hom  ‘ 𝐶 ) 𝑎 ) )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) ) | 
						
							| 73 | 18 72 | mpd | ⊢ ( 𝜑  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) ) | 
						
							| 74 | 73 | imp | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) | 
						
							| 75 | 74 | exlimdv | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ( ∃ 𝑘 𝑘  ∈  ( 𝐵 ( Iso ‘ 𝐶 ) 𝐴 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) | 
						
							| 76 | 15 75 | sylbid | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝐵 (  ≃𝑐  ‘ 𝐶 ) 𝐴  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) | 
						
							| 77 | 76 | adantr | ⊢ ( ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  ( 𝐵 (  ≃𝑐  ‘ 𝐶 ) 𝐴  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) ) | 
						
							| 78 | 10 77 | mpd | ⊢ ( ( ( 𝜑  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 79 | 78 | an32s | ⊢ ( ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝑏  ∈  ( Base ‘ 𝐶 )  →  ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 80 | 79 | ralrimiv | ⊢ ( ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ∀ 𝑏  ∈  ( Base ‘ 𝐶 ) ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) | 
						
							| 81 | 1 | ad2antrr | ⊢ ( ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐶  ∈  Cat ) | 
						
							| 82 |  | simprr | ⊢ ( ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐵  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 83 | 12 16 81 82 | isinito | ⊢ ( ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  ( 𝐵  ∈  ( InitO ‘ 𝐶 )  ↔  ∀ 𝑏  ∈  ( Base ‘ 𝐶 ) ∃! 𝑔 𝑔  ∈  ( 𝐵 ( Hom  ‘ 𝐶 ) 𝑏 ) ) ) | 
						
							| 84 | 80 83 | mpbird | ⊢ ( ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  ∧  ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) ) )  →  𝐵  ∈  ( InitO ‘ 𝐶 ) ) | 
						
							| 85 | 84 | ex | ⊢ ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  ( ( 𝐴  ∈  ( Base ‘ 𝐶 )  ∧  𝐵  ∈  ( Base ‘ 𝐶 ) )  →  𝐵  ∈  ( InitO ‘ 𝐶 ) ) ) | 
						
							| 86 | 5 7 85 | mp2and | ⊢ ( ( 𝜑  ∧  𝐴 (  ≃𝑐  ‘ 𝐶 ) 𝐵 )  →  𝐵  ∈  ( InitO ‘ 𝐶 ) ) | 
						
							| 87 | 3 86 | mpdan | ⊢ ( 𝜑  →  𝐵  ∈  ( InitO ‘ 𝐶 ) ) |