Metamath Proof Explorer


Theorem chrelat2

Description: A consequence of relative atomicity. (Contributed by NM, 1-Jul-2004) (New usage is discouraged.)

Ref Expression
Assertion chrelat2 ( ( 𝐴C𝐵C ) → ( ¬ 𝐴𝐵 ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥𝐴 ∧ ¬ 𝑥𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 sseq1 ( 𝐴 = if ( 𝐴C , 𝐴 , ℋ ) → ( 𝐴𝐵 ↔ if ( 𝐴C , 𝐴 , ℋ ) ⊆ 𝐵 ) )
2 1 notbid ( 𝐴 = if ( 𝐴C , 𝐴 , ℋ ) → ( ¬ 𝐴𝐵 ↔ ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ 𝐵 ) )
3 sseq2 ( 𝐴 = if ( 𝐴C , 𝐴 , ℋ ) → ( 𝑥𝐴𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ) )
4 3 anbi1d ( 𝐴 = if ( 𝐴C , 𝐴 , ℋ ) → ( ( 𝑥𝐴 ∧ ¬ 𝑥𝐵 ) ↔ ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥𝐵 ) ) )
5 4 rexbidv ( 𝐴 = if ( 𝐴C , 𝐴 , ℋ ) → ( ∃ 𝑥 ∈ HAtoms ( 𝑥𝐴 ∧ ¬ 𝑥𝐵 ) ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥𝐵 ) ) )
6 2 5 bibi12d ( 𝐴 = if ( 𝐴C , 𝐴 , ℋ ) → ( ( ¬ 𝐴𝐵 ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥𝐴 ∧ ¬ 𝑥𝐵 ) ) ↔ ( ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ 𝐵 ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥𝐵 ) ) ) )
7 sseq2 ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( if ( 𝐴C , 𝐴 , ℋ ) ⊆ 𝐵 ↔ if ( 𝐴C , 𝐴 , ℋ ) ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) )
8 7 notbid ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ 𝐵 ↔ ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) )
9 sseq2 ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( 𝑥𝐵𝑥 ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) )
10 9 notbid ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( ¬ 𝑥𝐵 ↔ ¬ 𝑥 ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) )
11 10 anbi2d ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥𝐵 ) ↔ ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥 ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) ) )
12 11 rexbidv ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥𝐵 ) ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥 ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) ) )
13 8 12 bibi12d ( 𝐵 = if ( 𝐵C , 𝐵 , ℋ ) → ( ( ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ 𝐵 ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥𝐵 ) ) ↔ ( ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ if ( 𝐵C , 𝐵 , ℋ ) ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥 ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) ) ) )
14 ifchhv if ( 𝐴C , 𝐴 , ℋ ) ∈ C
15 ifchhv if ( 𝐵C , 𝐵 , ℋ ) ∈ C
16 14 15 chrelat2i ( ¬ if ( 𝐴C , 𝐴 , ℋ ) ⊆ if ( 𝐵C , 𝐵 , ℋ ) ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥 ⊆ if ( 𝐴C , 𝐴 , ℋ ) ∧ ¬ 𝑥 ⊆ if ( 𝐵C , 𝐵 , ℋ ) ) )
17 6 13 16 dedth2h ( ( 𝐴C𝐵C ) → ( ¬ 𝐴𝐵 ↔ ∃ 𝑥 ∈ HAtoms ( 𝑥𝐴 ∧ ¬ 𝑥𝐵 ) ) )