Theorem vpwex 5241

Description: Power set axiom: the powerclass of a set is a set. Axiom 4 of [TakeutiZaring] p. 17. (Contributed by NM, 30-Oct-2003.) (Proof shortened by Andrew Salmon, 25-Jul-2011.) Revised to prove pwexg 5242 from vpwex 5241. (Revised by BJ, 10-Aug-2022.)

Assertion

Ref	Expression
vpwex	⊢ 𝒫 𝑥 ∈ V

Proof of Theorem vpwex

Dummy variables 𝑦 𝑧 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-pw 4487	. 2 ⊢ 𝒫 𝑥 = {𝑤 ∣ 𝑤 ⊆ 𝑥}
2		axpow2 5231	. . . . 5 ⊢ ∃𝑦∀𝑧(𝑧 ⊆ 𝑥 → 𝑧 ∈ 𝑦)
3	2	bm1.3ii 5167	. . . 4 ⊢ ∃𝑦∀𝑧(𝑧 ∈ 𝑦 ↔ 𝑧 ⊆ 𝑥)
4		sseq1 3900	. . . . . 6 ⊢ (𝑤 = 𝑧 → (𝑤 ⊆ 𝑥 ↔ 𝑧 ⊆ 𝑥))
5	4	abeq2w 2810	. . . . 5 ⊢ (𝑦 = {𝑤 ∣ 𝑤 ⊆ 𝑥} ↔ ∀𝑧(𝑧 ∈ 𝑦 ↔ 𝑧 ⊆ 𝑥))
6	5	exbii 1854	. . . 4 ⊢ (∃𝑦 𝑦 = {𝑤 ∣ 𝑤 ⊆ 𝑥} ↔ ∃𝑦∀𝑧(𝑧 ∈ 𝑦 ↔ 𝑧 ⊆ 𝑥))
7	3, 6	mpbir 234	. . 3 ⊢ ∃𝑦 𝑦 = {𝑤 ∣ 𝑤 ⊆ 𝑥}
8	7	issetri 3413	. 2 ⊢ {𝑤 ∣ 𝑤 ⊆ 𝑥} ∈ V
9	1, 8	eqeltri 2829	1 ⊢ 𝒫 𝑥 ∈ V

Syntax hints:   ↔ wb 209  ∀wal 1540   = wceq 1542  ∃wex 1786   ∈ wcel 2113  {cab 2716  Vcvv 3397   ⊆ wss 3841  𝒫 cpw 4485

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1802  ax-4 1816  ax-5 1916  ax-6 1974  ax-7 2019  ax-8 2115  ax-9 2123  ax-ext 2710  ax-sep 5164  ax-pow 5229

This theorem depends on definitions:  df-bi 210  df-an 400  df-tru 1545  df-ex 1787  df-sb 2074  df-clab 2717  df-cleq 2730  df-clel 2811  df-v 3399  df-in 3848  df-ss 3858  df-pw 4487

This theorem is referenced by:  pwexg  5242  pwnex  7494  inf3lem7  9163  dfac8  9628  dfac13  9635  ackbij1lem8  9720  dominf  9938  numthcor  9987  dominfac  10066  intwun  10228  wunex2  10231  eltsk2g  10244  inttsk  10267  tskcard  10274  intgru  10307  gruina  10311  axgroth6  10321  ismre  16957  fnmre  16958  mreacs  17025  isacs5lem  17888  pmtrfval  18689  istopon  21656  dmtopon  21667  tgdom  21722  isfbas  22573  bj-snglex  34775  exrecfnpw  35164  pwinfi  40700  ntrrn  41262  ntrf  41263  dssmapntrcls  41268