Theorem tskpw 10674

Description: Second axiom of a Tarski class. The powerset of an element of a Tarski class belongs to the class. (Contributed by FL, 30-Dec-2010.) (Proof shortened by Mario Carneiro, 20-Sep-2014.)

Assertion

Ref	Expression
tskpw	⊢ ((𝑇 ∈ Tarski ∧ 𝐴 ∈ 𝑇) → 𝒫 𝐴 ∈ 𝑇)

Proof of Theorem tskpw

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		eltsk2g 10672	. . . . 5 ⊢ (𝑇 ∈ Tarski → (𝑇 ∈ Tarski ↔ (∀𝑥 ∈ 𝑇 (𝒫 𝑥 ⊆ 𝑇 ∧ 𝒫 𝑥 ∈ 𝑇) ∧ ∀𝑥 ∈ 𝒫 𝑇(𝑥 ≈ 𝑇 ∨ 𝑥 ∈ 𝑇))))
2	1	ibi 268	. . . 4 ⊢ (𝑇 ∈ Tarski → (∀𝑥 ∈ 𝑇 (𝒫 𝑥 ⊆ 𝑇 ∧ 𝒫 𝑥 ∈ 𝑇) ∧ ∀𝑥 ∈ 𝒫 𝑇(𝑥 ≈ 𝑇 ∨ 𝑥 ∈ 𝑇)))
3	2	simpld 495	. . 3 ⊢ (𝑇 ∈ Tarski → ∀𝑥 ∈ 𝑇 (𝒫 𝑥 ⊆ 𝑇 ∧ 𝒫 𝑥 ∈ 𝑇))
4		simpr 485	. . . 4 ⊢ ((𝒫 𝑥 ⊆ 𝑇 ∧ 𝒫 𝑥 ∈ 𝑇) → 𝒫 𝑥 ∈ 𝑇)
5	4	ralimi 3077	. . 3 ⊢ (∀𝑥 ∈ 𝑇 (𝒫 𝑥 ⊆ 𝑇 ∧ 𝒫 𝑥 ∈ 𝑇) → ∀𝑥 ∈ 𝑇 𝒫 𝑥 ∈ 𝑇)
6	3, 5	syl 17	. 2 ⊢ (𝑇 ∈ Tarski → ∀𝑥 ∈ 𝑇 𝒫 𝑥 ∈ 𝑇)
7		pweq 4550	. . . 4 ⊢ (𝑥 = 𝐴 → 𝒫 𝑥 = 𝒫 𝐴)
8	7	eleq1d 2825	. . 3 ⊢ (𝑥 = 𝐴 → (𝒫 𝑥 ∈ 𝑇 ↔ 𝒫 𝐴 ∈ 𝑇))
9	8	rspccva 3566	. 2 ⊢ ((∀𝑥 ∈ 𝑇 𝒫 𝑥 ∈ 𝑇 ∧ 𝐴 ∈ 𝑇) → 𝒫 𝐴 ∈ 𝑇)
10	6, 9	sylan 586	1 ⊢ ((𝑇 ∈ Tarski ∧ 𝐴 ∈ 𝑇) → 𝒫 𝐴 ∈ 𝑇)

Syntax hints:   → wi 4   ∧ wa 396   ∨ wo 853   = wceq 1547   ∈ wcel 2119  ∀wral 3054   ⊆ wss 3890  𝒫 cpw 4536   class class class wbr 5079   ≈ cen 8887  Tarskictsk 10669

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 1917  ax-6 1974  ax-7 2015  ax-8 2121  ax-9 2129  ax-10 2152  ax-12 2189  ax-ext 2712  ax-sep 5225  ax-pow 5301

This theorem depends on definitions:  df-bi 208  df-an 397  df-or 854  df-3an 1094  df-tru 1550  df-fal 1560  df-ex 1787  df-nf 1791  df-sb 2074  df-clab 2719  df-cleq 2732  df-clel 2815  df-ral 3055  df-rex 3065  df-rab 3393  df-v 3434  df-dif 3893  df-un 3895  df-ss 3907  df-nul 4269  df-if 4462  df-pw 4538  df-sn 4563  df-pr 4565  df-op 4569  df-br 5080  df-tsk 10670

This theorem is referenced by:  tsksn  10681  tsksuc  10683  tskr1om  10688  inttsk  10695  tskcard  10702  tskwun  10705  grutsk1  10742  pwinfi3  44014