Metamath Proof Explorer


Theorem ordtype2

Description: For any set-like well-ordered class, if the order isomorphism exists (is a set), then it maps some ordinal onto A isomorphically. Otherwise, F is a proper class, which implies that either ran F C_ A is a proper class or dom F = On . This weak version of ordtype does not require the Axiom of Replacement. (Contributed by Mario Carneiro, 25-Jun-2015)

Ref Expression
Hypothesis oicl.1 𝐹 = OrdIso ( 𝑅 , 𝐴 )
Assertion ordtype2 ( ( 𝑅 We 𝐴𝑅 Se 𝐴𝐹 ∈ V ) → 𝐹 Isom E , 𝑅 ( dom 𝐹 , 𝐴 ) )

Proof

Step Hyp Ref Expression
1 oicl.1 𝐹 = OrdIso ( 𝑅 , 𝐴 )
2 eqid recs ( ( ∈ V ↦ ( 𝑣 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ∀ 𝑢 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ¬ 𝑢 𝑅 𝑣 ) ) ) = recs ( ( ∈ V ↦ ( 𝑣 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ∀ 𝑢 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ¬ 𝑢 𝑅 𝑣 ) ) )
3 eqid { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } = { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 }
4 eqid ( ∈ V ↦ ( 𝑣 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ∀ 𝑢 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ¬ 𝑢 𝑅 𝑣 ) ) = ( ∈ V ↦ ( 𝑣 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ∀ 𝑢 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ¬ 𝑢 𝑅 𝑣 ) )
5 2 3 4 ordtypecbv recs ( ( 𝑓 ∈ V ↦ ( 𝑠 ∈ { 𝑦𝐴 ∣ ∀ 𝑖 ∈ ran 𝑓 𝑖 𝑅 𝑦 } ∀ 𝑟 ∈ { 𝑦𝐴 ∣ ∀ 𝑖 ∈ ran 𝑓 𝑖 𝑅 𝑦 } ¬ 𝑟 𝑅 𝑠 ) ) ) = recs ( ( ∈ V ↦ ( 𝑣 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ∀ 𝑢 ∈ { 𝑤𝐴 ∣ ∀ 𝑗 ∈ ran 𝑗 𝑅 𝑤 } ¬ 𝑢 𝑅 𝑣 ) ) )
6 eqid { 𝑥 ∈ On ∣ ∃ 𝑡𝐴𝑧 ∈ ( recs ( ( 𝑓 ∈ V ↦ ( 𝑠 ∈ { 𝑦𝐴 ∣ ∀ 𝑖 ∈ ran 𝑓 𝑖 𝑅 𝑦 } ∀ 𝑟 ∈ { 𝑦𝐴 ∣ ∀ 𝑖 ∈ ran 𝑓 𝑖 𝑅 𝑦 } ¬ 𝑟 𝑅 𝑠 ) ) ) “ 𝑥 ) 𝑧 𝑅 𝑡 } = { 𝑥 ∈ On ∣ ∃ 𝑡𝐴𝑧 ∈ ( recs ( ( 𝑓 ∈ V ↦ ( 𝑠 ∈ { 𝑦𝐴 ∣ ∀ 𝑖 ∈ ran 𝑓 𝑖 𝑅 𝑦 } ∀ 𝑟 ∈ { 𝑦𝐴 ∣ ∀ 𝑖 ∈ ran 𝑓 𝑖 𝑅 𝑦 } ¬ 𝑟 𝑅 𝑠 ) ) ) “ 𝑥 ) 𝑧 𝑅 𝑡 }
7 simp1 ( ( 𝑅 We 𝐴𝑅 Se 𝐴𝐹 ∈ V ) → 𝑅 We 𝐴 )
8 simp2 ( ( 𝑅 We 𝐴𝑅 Se 𝐴𝐹 ∈ V ) → 𝑅 Se 𝐴 )
9 simp3 ( ( 𝑅 We 𝐴𝑅 Se 𝐴𝐹 ∈ V ) → 𝐹 ∈ V )
10 5 3 4 6 1 7 8 9 ordtypelem9 ( ( 𝑅 We 𝐴𝑅 Se 𝐴𝐹 ∈ V ) → 𝐹 Isom E , 𝑅 ( dom 𝐹 , 𝐴 ) )