Theorem relss 4806

Description: Subclass theorem for relation predicate. Theorem 2 of [Suppes] p. 58. (Contributed by NM, 15-Aug-1994.)

Assertion

Ref	Expression
relss	|- ( A C_ B -> ( Rel B -> Rel A ) )

Proof of Theorem relss

Step	Hyp	Ref	Expression
1		sstr2 3231	. 2 |- ( A C_ B -> ( B C_ ( _V X. _V ) -> A C_ ( _V X. _V ) ) )
2		df-rel 4726	. 2 |- ( Rel B <-> B C_ ( _V X. _V ) )
3		df-rel 4726	. 2 |- ( Rel A <-> A C_ ( _V X. _V ) )
4	1, 2, 3	3imtr4g 205	1 |- ( A C_ B -> ( Rel B -> Rel A ) )

Syntax hints:   -> wi 4   _Vcvv 2799   C_ wss 3197   X. cxp 4717   Rel wrel 4724

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-11 1552  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-ext 2211

This theorem depends on definitions:  df-bi 117  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-in 3203  df-ss 3210  df-rel 4726

This theorem is referenced by:  relin1  4837  relin2  4838  reldif  4839  relres  5033  iss  5051  cnvdif  5135  funss  5337  funssres  5360  fliftcnv  5919  fliftfun  5920  reltpos  6396  tpostpos  6410  swoer  6708  erinxp  6756  ltrel  8208  lerel  8210  txdis1cn  14952  xmeter  15110  lgsquadlem1  15756  lgsquadlem2  15757