Metamath Proof Explorer


Theorem fuconuniqex

Description: The object function of functor composition does not in general determine its morphism function, even when both source categories are the trivial category. The witness category is the explicit two-object, two-parallel-arrow category of par2cat . (Contributed by Zhi Wang, 14-Sep-2026)

Ref Expression
Assertion fuconuniqex ∃ 𝑒 ∈ Cat ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) )

Proof

Step Hyp Ref Expression
1 par2cat ⊢ { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ∈ Cat
2 eqid ⊢ ( SetCat ‘ 1o ) = ( SetCat ‘ 1o )
3 eqid ⊢ { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ }
4 eqid ⊢ ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) = ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } )
5 eqid ⊢ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) = ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } )
6 eqid ⊢ ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) = ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) )
7 2 3 4 5 6 fuconuniq2 ⊢ ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) )
8 oveq2 ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) = ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) )
9 8 fveq2d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) = ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) )
10 oveq2 ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) = ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) )
11 10 oveq1d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) = ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) )
12 11 10 oveq12d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) = ( ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) )
13 eqidd ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → 𝑧 = 𝑧 )
14 9 12 13 breq123d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) 𝑧 ↔ ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) 𝑧 ) )
15 8 fveq2d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) = ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) )
16 15 neeq2d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ↔ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ) )
17 14 16 anbi12d ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ) ↔ ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ) ) )
18 17 exbidv ⊢ ( 𝑒 = { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } → ( ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ) ↔ ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ) ) )
19 18 rspcev ⊢ ( ( { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ∈ Cat ∧ ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F { ⟨ ( Base ‘ ndx ) , 2o ⟩ , ⟨ ( Hom ‘ ndx ) , ( 𝑚 ∈ 2o , 𝑛 ∈ 2o ↦ if ( 𝑚 = 𝑛 , { 2o } , if ( ( 𝑚 = ∅ ∧ 𝑛 = 1o ) , 2o , ∅ ) ) ) ⟩ , ⟨ ( comp ‘ ndx ) , ( 𝑝 ∈ ( 2o × 2o ) , 𝑞 ∈ 2o ↦ ( 𝑟 ∈ 3o , 𝑠 ∈ 3o ↦ ( 𝑟 ∩ 𝑠 ) ) ) ⟩ } ) ) ) ) → ∃ 𝑒 ∈ Cat ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ) )
20 1 7 19 mp2an ⊢ ∃ 𝑒 ∈ Cat ∃ 𝑧 ( ( 1st ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) ( ( ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ×c ( ( SetCat ‘ 1o ) FuncCat ( SetCat ‘ 1o ) ) ) Func ( ( SetCat ‘ 1o ) FuncCat 𝑒 ) ) 𝑧 ∧ 𝑧 ≠ ( 2nd ‘ ( ⟨ ( SetCat ‘ 1o ) , ( SetCat ‘ 1o ) ⟩ ∘F 𝑒 ) ) )