Theorem axpow3 4229

Description: A variant of the Axiom of Power Sets ax-pow 4226. For any set x, there exists a set y whose members are exactly the subsets of x i.e. the power set of x. Axiom Pow of [BellMachover] p. 466. (Contributed by NM, 4-Jun-2006.)

Assertion

Ref	Expression
axpow3	|- E. y A. z ( z C_ x <-> z e. y )

Distinct variable group:   x, y, z

Proof of Theorem axpow3

Step	Hyp	Ref	Expression
1		axpow2 4228	. . 3 |- E. y A. z ( z C_ x -> z e. y )
2	1	bm1.3ii 4173	. 2 |- E. y A. z ( z e. y <-> z C_ x )
3		bicom 140	. . . 4 |- ( ( z C_ x <-> z e. y ) <-> ( z e. y <-> z C_ x ) )
4	3	albii 1494	. . 3 |- ( A. z ( z C_ x <-> z e. y ) <-> A. z ( z e. y <-> z C_ x ) )
5	4	exbii 1629	. 2 |- ( E. y A. z ( z C_ x <-> z e. y ) <-> E. y A. z ( z e. y <-> z C_ x ) )
6	2, 5	mpbir 146	1 |- E. y A. z ( z C_ x <-> z e. y )

Syntax hints:   <-> wb 105   A.wal 1371   E.wex 1516   C_ wss 3170

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 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-11 1530  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-14 2180  ax-ext 2188  ax-sep 4170  ax-pow 4226

This theorem depends on definitions:  df-bi 117  df-nf 1485  df-sb 1787  df-clab 2193  df-cleq 2199  df-clel 2202  df-in 3176  df-ss 3183

This theorem is referenced by: (None)