Theorem mrieqvd 17657

Description: In a Moore system, a set is independent if and only if, for all elements of the set, the closure of the set with the element removed is unequal to the closure of the original set. Part of Proposition 4.1.3 in [FaureFrolicher] p. 83. (Contributed by David Moews, 1-May-2017.)

Hypotheses

Ref	Expression
mrieqvd.1	⊢ (𝜑 → 𝐴 ∈ (Moore‘𝑋))
mrieqvd.2	⊢ 𝑁 = (mrCls‘𝐴)
mrieqvd.3	⊢ 𝐼 = (mrInd‘𝐴)
mrieqvd.4	⊢ (𝜑 → 𝑆 ⊆ 𝑋)

Assertion

Ref	Expression
mrieqvd	⊢ (𝜑 → (𝑆 ∈ 𝐼 ↔ ∀𝑥 ∈ 𝑆 (𝑁‘(𝑆 ∖ {𝑥})) ≠ (𝑁‘𝑆)))

Distinct variable groups:   𝑥,𝐴   𝑥,𝑆   𝜑,𝑥

Allowed substitution hints:   𝐼(𝑥)   𝑁(𝑥)   𝑋(𝑥)

Proof of Theorem mrieqvd

Step	Hyp	Ref	Expression
1		mrieqvd.2	. . 3 ⊢ 𝑁 = (mrCls‘𝐴)
2		mrieqvd.3	. . 3 ⊢ 𝐼 = (mrInd‘𝐴)
3		mrieqvd.1	. . 3 ⊢ (𝜑 → 𝐴 ∈ (Moore‘𝑋))
4		mrieqvd.4	. . 3 ⊢ (𝜑 → 𝑆 ⊆ 𝑋)
5	1, 2, 3, 4	ismri2d 17652	. 2 ⊢ (𝜑 → (𝑆 ∈ 𝐼 ↔ ∀𝑥 ∈ 𝑆 ¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥}))))
6	3	adantr 480	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑆) → 𝐴 ∈ (Moore‘𝑋))
7	4	adantr 480	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑆) → 𝑆 ⊆ 𝑋)
8		simpr 484	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑆) → 𝑥 ∈ 𝑆)
9	6, 1, 7, 8	mrieqvlemd 17648	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑆) → (𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ (𝑁‘(𝑆 ∖ {𝑥})) = (𝑁‘𝑆)))
10	9	necon3bbid 2968	. . 3 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝑆) → (¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ (𝑁‘(𝑆 ∖ {𝑥})) ≠ (𝑁‘𝑆)))
11	10	ralbidva 3163	. 2 ⊢ (𝜑 → (∀𝑥 ∈ 𝑆 ¬ 𝑥 ∈ (𝑁‘(𝑆 ∖ {𝑥})) ↔ ∀𝑥 ∈ 𝑆 (𝑁‘(𝑆 ∖ {𝑥})) ≠ (𝑁‘𝑆)))
12	5, 11	bitrd 279	1 ⊢ (𝜑 → (𝑆 ∈ 𝐼 ↔ ∀𝑥 ∈ 𝑆 (𝑁‘(𝑆 ∖ {𝑥})) ≠ (𝑁‘𝑆)))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 206   ∧ wa 395   = wceq 1539   ∈ wcel 2107   ≠ wne 2931  ∀wral 3050   ∖ cdif 3930   ⊆ wss 3933  {csn 4608  ‘cfv 6542  Moorecmre 17601  mrClscmrc 17602  mrIndcmri 17603

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1794  ax-4 1808  ax-5 1909  ax-6 1966  ax-7 2006  ax-8 2109  ax-9 2117  ax-10 2140  ax-11 2156  ax-12 2176  ax-ext 2706  ax-sep 5278  ax-nul 5288  ax-pow 5347  ax-pr 5414  ax-un 7738

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1779  df-nf 1783  df-sb 2064  df-mo 2538  df-eu 2567  df-clab 2713  df-cleq 2726  df-clel 2808  df-nfc 2884  df-ne 2932  df-ral 3051  df-rex 3060  df-rab 3421  df-v 3466  df-sbc 3773  df-csb 3882  df-dif 3936  df-un 3938  df-in 3940  df-ss 3950  df-nul 4316  df-if 4508  df-pw 4584  df-sn 4609  df-pr 4611  df-op 4615  df-uni 4890  df-int 4929  df-br 5126  df-opab 5188  df-mpt 5208  df-id 5560  df-xp 5673  df-rel 5674  df-cnv 5675  df-co 5676  df-dm 5677  df-rn 5678  df-res 5679  df-ima 5680  df-iota 6495  df-fun 6544  df-fn 6545  df-f 6546  df-fv 6550  df-mre 17605  df-mrc 17606  df-mri 17607

This theorem is referenced by: (None)