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Theorem cdlemb 34098
Description: Given two atoms not less than or equal to an element covered by 1, there is a third. Lemma B in [Crawley] p. 112. (Contributed by NM, 8-May-2012.)
Hypotheses
Ref Expression
cdlemb.b 𝐵 = (Base‘𝐾)
cdlemb.l = (le‘𝐾)
cdlemb.j = (join‘𝐾)
cdlemb.u 1 = (1.‘𝐾)
cdlemb.c 𝐶 = ( ⋖ ‘𝐾)
cdlemb.a 𝐴 = (Atoms‘𝐾)
Assertion
Ref Expression
cdlemb (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ∃𝑟𝐴𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄)))
Distinct variable groups:   𝐴,𝑟   𝐵,𝑟   𝐶,𝑟   ,𝑟   𝐾,𝑟   ,𝑟   𝑃,𝑟   𝑄,𝑟   1 ,𝑟   𝑋,𝑟

Proof of Theorem cdlemb
Dummy variable 𝑢 is distinct from all other variables.
StepHypRef Expression
1 simp11 1084 . . 3 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝐾 ∈ HL)
2 simp12 1085 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑃𝐴)
3 simp13 1086 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑄𝐴)
4 simp2l 1080 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑋𝐵)
5 simp2r 1081 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑃𝑄)
6 simp31 1090 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑋𝐶 1 )
7 simp32 1091 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ¬ 𝑃 𝑋)
8 cdlemb.b . . . . 5 𝐵 = (Base‘𝐾)
9 cdlemb.l . . . . 5 = (le‘𝐾)
10 cdlemb.j . . . . 5 = (join‘𝐾)
11 eqid 2610 . . . . 5 (meet‘𝐾) = (meet‘𝐾)
12 cdlemb.u . . . . 5 1 = (1.‘𝐾)
13 cdlemb.c . . . . 5 𝐶 = ( ⋖ ‘𝐾)
14 cdlemb.a . . . . 5 𝐴 = (Atoms‘𝐾)
158, 9, 10, 11, 12, 13, 141cvrat 33780 . . . 4 ((𝐾 ∈ HL ∧ (𝑃𝐴𝑄𝐴𝑋𝐵) ∧ (𝑃𝑄𝑋𝐶 1 ∧ ¬ 𝑃 𝑋)) → ((𝑃 𝑄)(meet‘𝐾)𝑋) ∈ 𝐴)
161, 2, 3, 4, 5, 6, 7, 15syl133anc 1341 . . 3 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ((𝑃 𝑄)(meet‘𝐾)𝑋) ∈ 𝐴)
17 hllat 33668 . . . . . 6 (𝐾 ∈ HL → 𝐾 ∈ Lat)
181, 17syl 17 . . . . 5 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝐾 ∈ Lat)
198, 14atbase 33594 . . . . . . 7 (𝑃𝐴𝑃𝐵)
202, 19syl 17 . . . . . 6 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑃𝐵)
218, 14atbase 33594 . . . . . . 7 (𝑄𝐴𝑄𝐵)
223, 21syl 17 . . . . . 6 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → 𝑄𝐵)
238, 10latjcl 16874 . . . . . 6 ((𝐾 ∈ Lat ∧ 𝑃𝐵𝑄𝐵) → (𝑃 𝑄) ∈ 𝐵)
2418, 20, 22, 23syl3anc 1318 . . . . 5 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → (𝑃 𝑄) ∈ 𝐵)
258, 9, 11latmle2 16900 . . . . 5 ((𝐾 ∈ Lat ∧ (𝑃 𝑄) ∈ 𝐵𝑋𝐵) → ((𝑃 𝑄)(meet‘𝐾)𝑋) 𝑋)
2618, 24, 4, 25syl3anc 1318 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ((𝑃 𝑄)(meet‘𝐾)𝑋) 𝑋)
27 eqid 2610 . . . . 5 (lt‘𝐾) = (lt‘𝐾)
288, 9, 27, 12, 13, 141cvratlt 33778 . . . 4 (((𝐾 ∈ HL ∧ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∈ 𝐴𝑋𝐵) ∧ (𝑋𝐶 1 ∧ ((𝑃 𝑄)(meet‘𝐾)𝑋) 𝑋)) → ((𝑃 𝑄)(meet‘𝐾)𝑋)(lt‘𝐾)𝑋)
291, 16, 4, 6, 26, 28syl32anc 1326 . . 3 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ((𝑃 𝑄)(meet‘𝐾)𝑋)(lt‘𝐾)𝑋)
308, 27, 142atlt 33743 . . 3 (((𝐾 ∈ HL ∧ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∈ 𝐴𝑋𝐵) ∧ ((𝑃 𝑄)(meet‘𝐾)𝑋)(lt‘𝐾)𝑋) → ∃𝑢𝐴 (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))
311, 16, 4, 29, 30syl31anc 1321 . 2 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ∃𝑢𝐴 (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))
32 simpl11 1129 . . . 4 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝐾 ∈ HL)
33 simpl12 1130 . . . 4 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝑃𝐴)
34 simprl 790 . . . 4 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝑢𝐴)
35 simpl32 1136 . . . . 5 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → ¬ 𝑃 𝑋)
36 simprrr 801 . . . . . . . 8 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝑢(lt‘𝐾)𝑋)
37 simpl2l 1107 . . . . . . . . 9 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝑋𝐵)
389, 27pltle 16784 . . . . . . . . 9 ((𝐾 ∈ HL ∧ 𝑢𝐴𝑋𝐵) → (𝑢(lt‘𝐾)𝑋𝑢 𝑋))
3932, 34, 37, 38syl3anc 1318 . . . . . . . 8 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → (𝑢(lt‘𝐾)𝑋𝑢 𝑋))
4036, 39mpd 15 . . . . . . 7 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝑢 𝑋)
41 breq1 4586 . . . . . . 7 (𝑃 = 𝑢 → (𝑃 𝑋𝑢 𝑋))
4240, 41syl5ibrcom 236 . . . . . 6 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → (𝑃 = 𝑢𝑃 𝑋))
4342necon3bd 2796 . . . . 5 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → (¬ 𝑃 𝑋𝑃𝑢))
4435, 43mpd 15 . . . 4 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → 𝑃𝑢)
459, 10, 14hlsupr 33690 . . . 4 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑢𝐴) ∧ 𝑃𝑢) → ∃𝑟𝐴 (𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢)))
4632, 33, 34, 44, 45syl31anc 1321 . . 3 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → ∃𝑟𝐴 (𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢)))
47 eqid 2610 . . . . . . . 8 ((𝑃 𝑄)(meet‘𝐾)𝑋) = ((𝑃 𝑄)(meet‘𝐾)𝑋)
488, 9, 10, 12, 13, 14, 27, 11, 47cdlemblem 34097 . . . . . . 7 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋)) ∧ (𝑟𝐴 ∧ (𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢)))) → (¬ 𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄)))
49483exp 1256 . . . . . 6 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ((𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋)) → ((𝑟𝐴 ∧ (𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢))) → (¬ 𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄)))))
5049exp4a 631 . . . . 5 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ((𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋)) → (𝑟𝐴 → ((𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢)) → (¬ 𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄))))))
5150imp 444 . . . 4 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → (𝑟𝐴 → ((𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢)) → (¬ 𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄)))))
5251reximdvai 2998 . . 3 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → (∃𝑟𝐴 (𝑟𝑃𝑟𝑢𝑟 (𝑃 𝑢)) → ∃𝑟𝐴𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄))))
5346, 52mpd 15 . 2 ((((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) ∧ (𝑢𝐴 ∧ (𝑢 ≠ ((𝑃 𝑄)(meet‘𝐾)𝑋) ∧ 𝑢(lt‘𝐾)𝑋))) → ∃𝑟𝐴𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄)))
5431, 53rexlimddv 3017 1 (((𝐾 ∈ HL ∧ 𝑃𝐴𝑄𝐴) ∧ (𝑋𝐵𝑃𝑄) ∧ (𝑋𝐶 1 ∧ ¬ 𝑃 𝑋 ∧ ¬ 𝑄 𝑋)) → ∃𝑟𝐴𝑟 𝑋 ∧ ¬ 𝑟 (𝑃 𝑄)))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wa 383  w3a 1031   = wceq 1475  wcel 1977  wne 2780  wrex 2897   class class class wbr 4583  cfv 5804  (class class class)co 6549  Basecbs 15695  lecple 15775  ltcplt 16764  joincjn 16767  meetcmee 16768  1.cp1 16861  Latclat 16868  ccvr 33567  Atomscatm 33568  HLchlt 33655
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847
This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-ral 2901  df-rex 2902  df-reu 2903  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-op 4132  df-uni 4373  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-id 4953  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-riota 6511  df-ov 6552  df-oprab 6553  df-preset 16751  df-poset 16769  df-plt 16781  df-lub 16797  df-glb 16798  df-join 16799  df-meet 16800  df-p0 16862  df-p1 16863  df-lat 16869  df-clat 16931  df-oposet 33481  df-ol 33483  df-oml 33484  df-covers 33571  df-ats 33572  df-atl 33603  df-cvlat 33627  df-hlat 33656
This theorem is referenced by:  cdlemb2  34345
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