Theorem brssc 17697

Description: The subcategory subset relation is a relation. (Contributed by Mario Carneiro, 6-Jan-2017.)

Assertion

Ref	Expression
brssc	⊢ (𝐻 ⊆cat 𝐽 ↔ ∃𝑡(𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥)))

Distinct variable groups:   𝑡,𝑠,𝑥,𝐻   𝐽,𝑠,𝑡,𝑥

Proof of Theorem brssc

Dummy variables ℎ 𝑗 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		sscrel 17696	. . 3 ⊢ Rel ⊆cat
2	1	brrelex12i 5687	. 2 ⊢ (𝐻 ⊆cat 𝐽 → (𝐻 ∈ V ∧ 𝐽 ∈ V))
3		vex 3449	. . . . . 6 ⊢ 𝑡 ∈ V
4	3, 3	xpex 7687	. . . . 5 ⊢ (𝑡 × 𝑡) ∈ V
5		fnex 7167	. . . . 5 ⊢ ((𝐽 Fn (𝑡 × 𝑡) ∧ (𝑡 × 𝑡) ∈ V) → 𝐽 ∈ V)
6	4, 5	mpan2 689	. . . 4 ⊢ (𝐽 Fn (𝑡 × 𝑡) → 𝐽 ∈ V)
7		elex 3463	. . . . 5 ⊢ (𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥) → 𝐻 ∈ V)
8	7	rexlimivw 3148	. . . 4 ⊢ (∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥) → 𝐻 ∈ V)
9	6, 8	anim12ci 614	. . 3 ⊢ ((𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥)) → (𝐻 ∈ V ∧ 𝐽 ∈ V))
10	9	exlimiv 1933	. 2 ⊢ (∃𝑡(𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥)) → (𝐻 ∈ V ∧ 𝐽 ∈ V))
11		simpr 485	. . . . . 6 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → 𝑗 = 𝐽)
12	11	fneq1d 6595	. . . . 5 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → (𝑗 Fn (𝑡 × 𝑡) ↔ 𝐽 Fn (𝑡 × 𝑡)))
13		simpl 483	. . . . . . 7 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → ℎ = 𝐻)
14	11	fveq1d 6844	. . . . . . . . 9 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → (𝑗‘𝑥) = (𝐽‘𝑥))
15	14	pweqd 4577	. . . . . . . 8 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → 𝒫 (𝑗‘𝑥) = 𝒫 (𝐽‘𝑥))
16	15	ixpeq2dv 8851	. . . . . . 7 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝑗‘𝑥) = X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥))
17	13, 16	eleq12d 2832	. . . . . 6 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → (ℎ ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝑗‘𝑥) ↔ 𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥)))
18	17	rexbidv 3175	. . . . 5 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → (∃𝑠 ∈ 𝒫 𝑡ℎ ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝑗‘𝑥) ↔ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥)))
19	12, 18	anbi12d 631	. . . 4 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → ((𝑗 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡ℎ ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝑗‘𝑥)) ↔ (𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥))))
20	19	exbidv 1924	. . 3 ⊢ ((ℎ = 𝐻 ∧ 𝑗 = 𝐽) → (∃𝑡(𝑗 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡ℎ ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝑗‘𝑥)) ↔ ∃𝑡(𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥))))
21		df-ssc 17693	. . 3 ⊢ ⊆cat = {⟨ℎ, 𝑗⟩ ∣ ∃𝑡(𝑗 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡ℎ ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝑗‘𝑥))}
22	20, 21	brabga 5491	. 2 ⊢ ((𝐻 ∈ V ∧ 𝐽 ∈ V) → (𝐻 ⊆cat 𝐽 ↔ ∃𝑡(𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥))))
23	2, 10, 22	pm5.21nii 379	1 ⊢ (𝐻 ⊆cat 𝐽 ↔ ∃𝑡(𝐽 Fn (𝑡 × 𝑡) ∧ ∃𝑠 ∈ 𝒫 𝑡𝐻 ∈ X𝑥 ∈ (𝑠 × 𝑠)𝒫 (𝐽‘𝑥)))

Syntax hints:   ↔ wb 205   ∧ wa 396   = wceq 1541  ∃wex 1781   ∈ wcel 2106  ∃wrex 3073  Vcvv 3445  𝒫 cpw 4560   class class class wbr 5105   × cxp 5631   Fn wfn 6491  ‘cfv 6496  Xcixp 8835   ⊆_cat cssc 17690

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2707  ax-rep 5242  ax-sep 5256  ax-nul 5263  ax-pow 5320  ax-pr 5384  ax-un 7672

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-mo 2538  df-eu 2567  df-clab 2714  df-cleq 2728  df-clel 2814  df-nfc 2889  df-ne 2944  df-ral 3065  df-rex 3074  df-reu 3354  df-rab 3408  df-v 3447  df-sbc 3740  df-csb 3856  df-dif 3913  df-un 3915  df-in 3917  df-ss 3927  df-nul 4283  df-if 4487  df-pw 4562  df-sn 4587  df-pr 4589  df-op 4593  df-uni 4866  df-iun 4956  df-br 5106  df-opab 5168  df-mpt 5189  df-id 5531  df-xp 5639  df-rel 5640  df-cnv 5641  df-co 5642  df-dm 5643  df-rn 5644  df-res 5645  df-ima 5646  df-iota 6448  df-fun 6498  df-fn 6499  df-f 6500  df-f1 6501  df-fo 6502  df-f1o 6503  df-fv 6504  df-ixp 8836  df-ssc 17693

This theorem is referenced by:  sscpwex  17698  sscfn1  17700  sscfn2  17701  isssc  17703