Theorem omllaw 40116

Description: The orthomodular law. (Contributed by NM, 18-Sep-2011.)

Hypotheses

Ref	Expression
omllaw.b	⊢ 𝐵 = (Base‘𝐾)
omllaw.l	⊢ ≤ = (le‘𝐾)
omllaw.j	⊢ ∨ = (join‘𝐾)
omllaw.m	⊢ ∧ = (meet‘𝐾)
omllaw.o	⊢ ⊥ = (oc‘𝐾)

Assertion

Ref	Expression
omllaw	⊢ ((𝐾 ∈ OML ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → (𝑋 ≤ 𝑌 → 𝑌 = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋)))))

Proof of Theorem omllaw

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		omllaw.b	. . . . 5 ⊢ 𝐵 = (Base‘𝐾)
2		omllaw.l	. . . . 5 ⊢ ≤ = (le‘𝐾)
3		omllaw.j	. . . . 5 ⊢ ∨ = (join‘𝐾)
4		omllaw.m	. . . . 5 ⊢ ∧ = (meet‘𝐾)
5		omllaw.o	. . . . 5 ⊢ ⊥ = (oc‘𝐾)
6	1, 2, 3, 4, 5	isoml 40111	. . . 4 ⊢ (𝐾 ∈ OML ↔ (𝐾 ∈ OL ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 (𝑥 ≤ 𝑦 → 𝑦 = (𝑥 ∨ (𝑦 ∧ ( ⊥ ‘𝑥))))))
7	6	simprbi 503	. . 3 ⊢ (𝐾 ∈ OML → ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 (𝑥 ≤ 𝑦 → 𝑦 = (𝑥 ∨ (𝑦 ∧ ( ⊥ ‘𝑥)))))
8		breq1 5106	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑥 ≤ 𝑦 ↔ 𝑋 ≤ 𝑦))
9		id 23	. . . . . . 7 ⊢ (𝑥 = 𝑋 → 𝑥 = 𝑋)
10		fveq2 6878	. . . . . . . 8 ⊢ (𝑥 = 𝑋 → ( ⊥ ‘𝑥) = ( ⊥ ‘𝑋))
11	10	oveq2d 7429	. . . . . . 7 ⊢ (𝑥 = 𝑋 → (𝑦 ∧ ( ⊥ ‘𝑥)) = (𝑦 ∧ ( ⊥ ‘𝑋)))
12	9, 11	oveq12d 7431	. . . . . 6 ⊢ (𝑥 = 𝑋 → (𝑥 ∨ (𝑦 ∧ ( ⊥ ‘𝑥))) = (𝑋 ∨ (𝑦 ∧ ( ⊥ ‘𝑋))))
13	12	eqeq2d 2771	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑦 = (𝑥 ∨ (𝑦 ∧ ( ⊥ ‘𝑥))) ↔ 𝑦 = (𝑋 ∨ (𝑦 ∧ ( ⊥ ‘𝑋)))))
14	8, 13	imbi12d 347	. . . 4 ⊢ (𝑥 = 𝑋 → ((𝑥 ≤ 𝑦 → 𝑦 = (𝑥 ∨ (𝑦 ∧ ( ⊥ ‘𝑥)))) ↔ (𝑋 ≤ 𝑦 → 𝑦 = (𝑋 ∨ (𝑦 ∧ ( ⊥ ‘𝑋))))))
15		breq2 5107	. . . . 5 ⊢ (𝑦 = 𝑌 → (𝑋 ≤ 𝑦 ↔ 𝑋 ≤ 𝑌))
16		id 23	. . . . . 6 ⊢ (𝑦 = 𝑌 → 𝑦 = 𝑌)
17		oveq1 7420	. . . . . . 7 ⊢ (𝑦 = 𝑌 → (𝑦 ∧ ( ⊥ ‘𝑋)) = (𝑌 ∧ ( ⊥ ‘𝑋)))
18	17	oveq2d 7429	. . . . . 6 ⊢ (𝑦 = 𝑌 → (𝑋 ∨ (𝑦 ∧ ( ⊥ ‘𝑋))) = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋))))
19	16, 18	eqeq12d 2776	. . . . 5 ⊢ (𝑦 = 𝑌 → (𝑦 = (𝑋 ∨ (𝑦 ∧ ( ⊥ ‘𝑋))) ↔ 𝑌 = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋)))))
20	15, 19	imbi12d 347	. . . 4 ⊢ (𝑦 = 𝑌 → ((𝑋 ≤ 𝑦 → 𝑦 = (𝑋 ∨ (𝑦 ∧ ( ⊥ ‘𝑋)))) ↔ (𝑋 ≤ 𝑌 → 𝑌 = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋))))))
21	14, 20	rspc2v 3587	. . 3 ⊢ ((𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → (∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 (𝑥 ≤ 𝑦 → 𝑦 = (𝑥 ∨ (𝑦 ∧ ( ⊥ ‘𝑥)))) → (𝑋 ≤ 𝑌 → 𝑌 = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋))))))
22	7, 21	syl5com 32	. 2 ⊢ (𝐾 ∈ OML → ((𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → (𝑋 ≤ 𝑌 → 𝑌 = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋))))))
23	22	3impib 1134	1 ⊢ ((𝐾 ∈ OML ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → (𝑋 ≤ 𝑌 → 𝑌 = (𝑋 ∨ (𝑌 ∧ ( ⊥ ‘𝑋)))))

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   ∧ w3a 1103   = wceq 1570   ∈ wcel 2145  ∀wral 3076   class class class wbr 5103  ‘cfv 6533  (class class class)co 7413  Basecbs 17301  lecple 17349  occoc 17350  joincjn 18399  meetcmee 18400  OLcol 40047  OMLcoml 40048

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-ext 2732

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2100  df-clab 2739  df-cleq 2752  df-clel 2835  df-ral 3077  df-rab 3413  df-v 3452  df-dif 3902  df-un 3904  df-ss 3916  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-iota 6489  df-fv 6541  df-ov 7416  df-oml 40052

This theorem is used by:  omllaw2N  40117  omllaw3  40118  omllaw4  40119