Theorem sorpssint 7279

Description: In a chain of sets, a minimal element is the intersection of the chain. (Contributed by Stefan O'Rear, 2-Nov-2014.)

Assertion

Ref	Expression
sorpssint	⊢ ( [⊊] Or 𝑌 → (∃𝑢 ∈ 𝑌 ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢 ↔ ∩ 𝑌 ∈ 𝑌))

Distinct variable group:   𝑢,𝑌,𝑣

Proof of Theorem sorpssint

Step	Hyp	Ref	Expression
1		intss1 4765	. . . . . 6 ⊢ (𝑢 ∈ 𝑌 → ∩ 𝑌 ⊆ 𝑢)
2	1	3ad2ant2 1114	. . . . 5 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢) → ∩ 𝑌 ⊆ 𝑢)
3		sorpssi 7275	. . . . . . . . . 10 ⊢ (( [⊊] Or 𝑌 ∧ (𝑢 ∈ 𝑌 ∧ 𝑣 ∈ 𝑌)) → (𝑢 ⊆ 𝑣 ∨ 𝑣 ⊆ 𝑢))
4	3	anassrs 460	. . . . . . . . 9 ⊢ ((( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌) ∧ 𝑣 ∈ 𝑌) → (𝑢 ⊆ 𝑣 ∨ 𝑣 ⊆ 𝑢))
5		sspss 3968	. . . . . . . . . . 11 ⊢ (𝑣 ⊆ 𝑢 ↔ (𝑣 ⊊ 𝑢 ∨ 𝑣 = 𝑢))
6		orel1 872	. . . . . . . . . . . 12 ⊢ (¬ 𝑣 ⊊ 𝑢 → ((𝑣 ⊊ 𝑢 ∨ 𝑣 = 𝑢) → 𝑣 = 𝑢))
7		eqimss2 3916	. . . . . . . . . . . 12 ⊢ (𝑣 = 𝑢 → 𝑢 ⊆ 𝑣)
8	6, 7	syl6com 37	. . . . . . . . . . 11 ⊢ ((𝑣 ⊊ 𝑢 ∨ 𝑣 = 𝑢) → (¬ 𝑣 ⊊ 𝑢 → 𝑢 ⊆ 𝑣))
9	5, 8	sylbi 209	. . . . . . . . . 10 ⊢ (𝑣 ⊆ 𝑢 → (¬ 𝑣 ⊊ 𝑢 → 𝑢 ⊆ 𝑣))
10	9	jao1i 844	. . . . . . . . 9 ⊢ ((𝑢 ⊆ 𝑣 ∨ 𝑣 ⊆ 𝑢) → (¬ 𝑣 ⊊ 𝑢 → 𝑢 ⊆ 𝑣))
11	4, 10	syl 17	. . . . . . . 8 ⊢ ((( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌) ∧ 𝑣 ∈ 𝑌) → (¬ 𝑣 ⊊ 𝑢 → 𝑢 ⊆ 𝑣))
12	11	ralimdva 3127	. . . . . . 7 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌) → (∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢 → ∀𝑣 ∈ 𝑌 𝑢 ⊆ 𝑣))
13	12	3impia 1097	. . . . . 6 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢) → ∀𝑣 ∈ 𝑌 𝑢 ⊆ 𝑣)
14		ssint 4766	. . . . . 6 ⊢ (𝑢 ⊆ ∩ 𝑌 ↔ ∀𝑣 ∈ 𝑌 𝑢 ⊆ 𝑣)
15	13, 14	sylibr 226	. . . . 5 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢) → 𝑢 ⊆ ∩ 𝑌)
16	2, 15	eqssd 3877	. . . 4 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢) → ∩ 𝑌 = 𝑢)
17		simp2 1117	. . . 4 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢) → 𝑢 ∈ 𝑌)
18	16, 17	eqeltrd 2866	. . 3 ⊢ (( [⊊] Or 𝑌 ∧ 𝑢 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢) → ∩ 𝑌 ∈ 𝑌)
19	18	rexlimdv3a 3231	. 2 ⊢ ( [⊊] Or 𝑌 → (∃𝑢 ∈ 𝑌 ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢 → ∩ 𝑌 ∈ 𝑌))
20		intss1 4765	. . . . 5 ⊢ (𝑣 ∈ 𝑌 → ∩ 𝑌 ⊆ 𝑣)
21		ssnpss 3972	. . . . 5 ⊢ (∩ 𝑌 ⊆ 𝑣 → ¬ 𝑣 ⊊ ∩ 𝑌)
22	20, 21	syl 17	. . . 4 ⊢ (𝑣 ∈ 𝑌 → ¬ 𝑣 ⊊ ∩ 𝑌)
23	22	rgen 3098	. . 3 ⊢ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ ∩ 𝑌
24		psseq2 3957	. . . . . 6 ⊢ (𝑢 = ∩ 𝑌 → (𝑣 ⊊ 𝑢 ↔ 𝑣 ⊊ ∩ 𝑌))
25	24	notbid 310	. . . . 5 ⊢ (𝑢 = ∩ 𝑌 → (¬ 𝑣 ⊊ 𝑢 ↔ ¬ 𝑣 ⊊ ∩ 𝑌))
26	25	ralbidv 3147	. . . 4 ⊢ (𝑢 = ∩ 𝑌 → (∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢 ↔ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ ∩ 𝑌))
27	26	rspcev 3535	. . 3 ⊢ ((∩ 𝑌 ∈ 𝑌 ∧ ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ ∩ 𝑌) → ∃𝑢 ∈ 𝑌 ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢)
28	23, 27	mpan2 678	. 2 ⊢ (∩ 𝑌 ∈ 𝑌 → ∃𝑢 ∈ 𝑌 ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢)
29	19, 28	impbid1 217	1 ⊢ ( [⊊] Or 𝑌 → (∃𝑢 ∈ 𝑌 ∀𝑣 ∈ 𝑌 ¬ 𝑣 ⊊ 𝑢 ↔ ∩ 𝑌 ∈ 𝑌))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 198   ∧ wa 387   ∨ wo 833   ∧ w3a 1068   = wceq 1507   ∈ wcel 2050  ∀wral 3088  ∃wrex 3089   ⊆ wss 3831   ⊊ wpss 3832  ∩ cint 4750   Or wor 5326   [⊊] crpss 7268

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1758  ax-4 1772  ax-5 1869  ax-6 1928  ax-7 1965  ax-8 2052  ax-9 2059  ax-10 2079  ax-11 2093  ax-12 2106  ax-13 2301  ax-ext 2750  ax-sep 5061  ax-nul 5068  ax-pr 5187

This theorem depends on definitions:  df-bi 199  df-an 388  df-or 834  df-3or 1069  df-3an 1070  df-tru 1510  df-ex 1743  df-nf 1747  df-sb 2016  df-mo 2547  df-eu 2583  df-clab 2759  df-cleq 2771  df-clel 2846  df-nfc 2918  df-ne 2968  df-ral 3093  df-rex 3094  df-rab 3097  df-v 3417  df-dif 3834  df-un 3836  df-in 3838  df-ss 3845  df-pss 3847  df-nul 4181  df-if 4352  df-sn 4443  df-pr 4445  df-op 4449  df-int 4751  df-br 4931  df-opab 4993  df-so 5328  df-xp 5414  df-rel 5415  df-rpss 7269

This theorem is referenced by:  fin2i2  9540  isfin2-2  9541