Theorem abssi 3259

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 3256	. 2 |- { x | ph } C_ { x | x e. A }
3		abid2 2317	. 2 |- { x | x e. A } = A
4	2, 3	sseqtri 3218	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  3268  abf  3495  intab  3904  opabss  4098  relopabi  4792  exse2  5044  mpoexw  6280  tfrlem8  6385  frecabex  6465  fiprc  6883  fival  7045  nqprxx  7630  ltnqex  7633  gtnqex  7634  recexprlemell  7706  recexprlemelu  7707  recexprlempr  7716  4sqlem1  12582  topnex  14406  2sqlem7  15446