Metamath Proof Explorer


Theorem poeq1

Description: Equality theorem for partial ordering predicate. (Contributed by NM, 27-Mar-1997)

Ref Expression
Assertion poeq1 ( 𝑅 = 𝑆 → ( 𝑅 Po 𝐴𝑆 Po 𝐴 ) )

Proof

Step Hyp Ref Expression
1 breq ( 𝑅 = 𝑆 → ( 𝑥 𝑅 𝑥𝑥 𝑆 𝑥 ) )
2 1 notbid ( 𝑅 = 𝑆 → ( ¬ 𝑥 𝑅 𝑥 ↔ ¬ 𝑥 𝑆 𝑥 ) )
3 breq ( 𝑅 = 𝑆 → ( 𝑥 𝑅 𝑦𝑥 𝑆 𝑦 ) )
4 breq ( 𝑅 = 𝑆 → ( 𝑦 𝑅 𝑧𝑦 𝑆 𝑧 ) )
5 3 4 anbi12d ( 𝑅 = 𝑆 → ( ( 𝑥 𝑅 𝑦𝑦 𝑅 𝑧 ) ↔ ( 𝑥 𝑆 𝑦𝑦 𝑆 𝑧 ) ) )
6 breq ( 𝑅 = 𝑆 → ( 𝑥 𝑅 𝑧𝑥 𝑆 𝑧 ) )
7 5 6 imbi12d ( 𝑅 = 𝑆 → ( ( ( 𝑥 𝑅 𝑦𝑦 𝑅 𝑧 ) → 𝑥 𝑅 𝑧 ) ↔ ( ( 𝑥 𝑆 𝑦𝑦 𝑆 𝑧 ) → 𝑥 𝑆 𝑧 ) ) )
8 2 7 anbi12d ( 𝑅 = 𝑆 → ( ( ¬ 𝑥 𝑅 𝑥 ∧ ( ( 𝑥 𝑅 𝑦𝑦 𝑅 𝑧 ) → 𝑥 𝑅 𝑧 ) ) ↔ ( ¬ 𝑥 𝑆 𝑥 ∧ ( ( 𝑥 𝑆 𝑦𝑦 𝑆 𝑧 ) → 𝑥 𝑆 𝑧 ) ) ) )
9 8 ralbidv ( 𝑅 = 𝑆 → ( ∀ 𝑧𝐴 ( ¬ 𝑥 𝑅 𝑥 ∧ ( ( 𝑥 𝑅 𝑦𝑦 𝑅 𝑧 ) → 𝑥 𝑅 𝑧 ) ) ↔ ∀ 𝑧𝐴 ( ¬ 𝑥 𝑆 𝑥 ∧ ( ( 𝑥 𝑆 𝑦𝑦 𝑆 𝑧 ) → 𝑥 𝑆 𝑧 ) ) ) )
10 9 2ralbidv ( 𝑅 = 𝑆 → ( ∀ 𝑥𝐴𝑦𝐴𝑧𝐴 ( ¬ 𝑥 𝑅 𝑥 ∧ ( ( 𝑥 𝑅 𝑦𝑦 𝑅 𝑧 ) → 𝑥 𝑅 𝑧 ) ) ↔ ∀ 𝑥𝐴𝑦𝐴𝑧𝐴 ( ¬ 𝑥 𝑆 𝑥 ∧ ( ( 𝑥 𝑆 𝑦𝑦 𝑆 𝑧 ) → 𝑥 𝑆 𝑧 ) ) ) )
11 df-po ( 𝑅 Po 𝐴 ↔ ∀ 𝑥𝐴𝑦𝐴𝑧𝐴 ( ¬ 𝑥 𝑅 𝑥 ∧ ( ( 𝑥 𝑅 𝑦𝑦 𝑅 𝑧 ) → 𝑥 𝑅 𝑧 ) ) )
12 df-po ( 𝑆 Po 𝐴 ↔ ∀ 𝑥𝐴𝑦𝐴𝑧𝐴 ( ¬ 𝑥 𝑆 𝑥 ∧ ( ( 𝑥 𝑆 𝑦𝑦 𝑆 𝑧 ) → 𝑥 𝑆 𝑧 ) ) )
13 10 11 12 3bitr4g ( 𝑅 = 𝑆 → ( 𝑅 Po 𝐴𝑆 Po 𝐴 ) )