Metamath Proof Explorer


Theorem scottssr1

Description: Relationship between a Scott's trick set and the cumulative hierarchy. (Contributed by BTernaryTau, 3-Jul-2026)

Ref Expression
Assertion scottssr1
|- ( A e. B -> Scott B C_ ( R1 ` suc ( rank ` A ) ) )

Proof

Step Hyp Ref Expression
1 rankscottu
 |-  ( A e. B -> ( rank ` Scott B ) C_ suc ( rank ` A ) )
2 rankon
 |-  ( rank ` A ) e. On
3 2 onsuci
 |-  suc ( rank ` A ) e. On
4 scottex2
 |-  Scott B e. _V
5 4 rankr1b
 |-  ( suc ( rank ` A ) e. On -> ( Scott B C_ ( R1 ` suc ( rank ` A ) ) <-> ( rank ` Scott B ) C_ suc ( rank ` A ) ) )
6 3 5 ax-mp
 |-  ( Scott B C_ ( R1 ` suc ( rank ` A ) ) <-> ( rank ` Scott B ) C_ suc ( rank ` A ) )
7 1 6 sylibr
 |-  ( A e. B -> Scott B C_ ( R1 ` suc ( rank ` A ) ) )