Theorem abssi 3258

Description: Inference of abstraction subclass from implication. (Contributed by NM, 20-Jan-2006.)

Hypothesis

Ref	Expression
abssi.1	|- ( ph -> x e. A )

Assertion

Ref	Expression
abssi	|- { x | ph } C_ A

Distinct variable group:   x, A

Allowed substitution hint:   ph( x)

Proof of Theorem abssi

Step	Hyp	Ref	Expression
1		abssi.1	. . 3 |- ( ph -> x e. A )
2	1	ss2abi 3255	. 2 |- { x | ph } C_ { x | x e. A }
3		abid2 2317	. 2 |- { x | x e. A } = A
4	2, 3	sseqtri 3217	1 |- { x | ph } C_ A

Syntax hints:   -> wi 4   e. wcel 2167   {cab 2182   C_ wss 3157

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-io 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178

This theorem depends on definitions:  df-bi 117  df-nf 1475  df-sb 1777  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-in 3163  df-ss 3170

This theorem is referenced by:  ssab2  3267  abf  3494  intab  3903  opabss  4097  relopabi  4791  exse2  5043  mpoexw  6271  tfrlem8  6376  frecabex  6456  fiprc  6874  fival  7036  nqprxx  7613  ltnqex  7616  gtnqex  7617  recexprlemell  7689  recexprlemelu  7690  recexprlempr  7699  4sqlem1  12557  topnex  14322  2sqlem7  15362