| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | simp11 1203 | . . . 4
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝐾 ∈ HL) | 
| 2 |  | simp12 1204 | . . . 4
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝑋 ∈ 𝐵) | 
| 3 | 1, 2 | jca 511 | . . 3
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵)) | 
| 4 |  | simp13 1205 | . . 3
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (𝑀‘𝑋) ∈ 𝑁) | 
| 5 |  | lneq2at.b | . . . . 5
⊢ 𝐵 = (Base‘𝐾) | 
| 6 |  | lneq2at.j | . . . . 5
⊢  ∨ =
(join‘𝐾) | 
| 7 |  | lneq2at.a | . . . . 5
⊢ 𝐴 = (Atoms‘𝐾) | 
| 8 |  | lneq2at.n | . . . . 5
⊢ 𝑁 = (Lines‘𝐾) | 
| 9 |  | lneq2at.m | . . . . 5
⊢ 𝑀 = (pmap‘𝐾) | 
| 10 | 5, 6, 7, 8, 9 | isline3 39779 | . . . 4
⊢ ((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵) → ((𝑀‘𝑋) ∈ 𝑁 ↔ ∃𝑟 ∈ 𝐴 ∃𝑠 ∈ 𝐴 (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠)))) | 
| 11 | 10 | biimpd 229 | . . 3
⊢ ((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵) → ((𝑀‘𝑋) ∈ 𝑁 → ∃𝑟 ∈ 𝐴 ∃𝑠 ∈ 𝐴 (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠)))) | 
| 12 | 3, 4, 11 | sylc 65 | . 2
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → ∃𝑟 ∈ 𝐴 ∃𝑠 ∈ 𝐴 (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) | 
| 13 |  | simp3r 1202 | . . . . 5
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → 𝑋 = (𝑟 ∨ 𝑠)) | 
| 14 |  | simp111 1302 | . . . . . . . 8
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → 𝐾 ∈ HL) | 
| 15 |  | simp121 1305 | . . . . . . . . 9
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → 𝑃 ∈ 𝐴) | 
| 16 |  | simp122 1306 | . . . . . . . . 9
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → 𝑄 ∈ 𝐴) | 
| 17 | 15, 16 | jca 511 | . . . . . . . 8
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴)) | 
| 18 |  | simp2 1137 | . . . . . . . 8
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) | 
| 19 | 14, 17, 18 | 3jca 1128 | . . . . . . 7
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → (𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴))) | 
| 20 |  | simp123 1307 | . . . . . . 7
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → 𝑃 ≠ 𝑄) | 
| 21 | 19, 20 | jca 511 | . . . . . 6
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → ((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄)) | 
| 22 | 1 | hllatd 39366 | . . . . . . . . . 10
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝐾 ∈ Lat) | 
| 23 |  | simp21 1206 | . . . . . . . . . . . 12
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝑃 ∈ 𝐴) | 
| 24 | 5, 7 | atbase 39291 | . . . . . . . . . . . 12
⊢ (𝑃 ∈ 𝐴 → 𝑃 ∈ 𝐵) | 
| 25 | 23, 24 | syl 17 | . . . . . . . . . . 11
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝑃 ∈ 𝐵) | 
| 26 |  | simp22 1207 | . . . . . . . . . . . 12
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝑄 ∈ 𝐴) | 
| 27 | 5, 7 | atbase 39291 | . . . . . . . . . . . 12
⊢ (𝑄 ∈ 𝐴 → 𝑄 ∈ 𝐵) | 
| 28 | 26, 27 | syl 17 | . . . . . . . . . . 11
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝑄 ∈ 𝐵) | 
| 29 | 25, 28, 2 | 3jca 1128 | . . . . . . . . . 10
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (𝑃 ∈ 𝐵 ∧ 𝑄 ∈ 𝐵 ∧ 𝑋 ∈ 𝐵)) | 
| 30 | 22, 29 | jca 511 | . . . . . . . . 9
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (𝐾 ∈ Lat ∧ (𝑃 ∈ 𝐵 ∧ 𝑄 ∈ 𝐵 ∧ 𝑋 ∈ 𝐵))) | 
| 31 |  | simp3 1138 | . . . . . . . . 9
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) | 
| 32 |  | lneq2at.l | . . . . . . . . . . 11
⊢  ≤ =
(le‘𝐾) | 
| 33 | 5, 32, 6 | latjle12 18496 | . . . . . . . . . 10
⊢ ((𝐾 ∈ Lat ∧ (𝑃 ∈ 𝐵 ∧ 𝑄 ∈ 𝐵 ∧ 𝑋 ∈ 𝐵)) → ((𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋) ↔ (𝑃 ∨ 𝑄) ≤ 𝑋)) | 
| 34 | 33 | biimpd 229 | . . . . . . . . 9
⊢ ((𝐾 ∈ Lat ∧ (𝑃 ∈ 𝐵 ∧ 𝑄 ∈ 𝐵 ∧ 𝑋 ∈ 𝐵)) → ((𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋) → (𝑃 ∨ 𝑄) ≤ 𝑋)) | 
| 35 | 30, 31, 34 | sylc 65 | . . . . . . . 8
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (𝑃 ∨ 𝑄) ≤ 𝑋) | 
| 36 | 35 | 3ad2ant1 1133 | . . . . . . 7
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → (𝑃 ∨ 𝑄) ≤ 𝑋) | 
| 37 | 36, 13 | breqtrd 5168 | . . . . . 6
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → (𝑃 ∨ 𝑄) ≤ (𝑟 ∨ 𝑠)) | 
| 38 |  | simpl1 1191 | . . . . . . . 8
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → 𝐾 ∈ HL) | 
| 39 |  | simpl2l 1226 | . . . . . . . 8
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → 𝑃 ∈ 𝐴) | 
| 40 |  | simpl2r 1227 | . . . . . . . 8
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → 𝑄 ∈ 𝐴) | 
| 41 |  | simpr 484 | . . . . . . . 8
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → 𝑃 ≠ 𝑄) | 
| 42 |  | simpl3 1193 | . . . . . . . 8
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) | 
| 43 | 32, 6, 7 | ps-1 39480 | . . . . . . . 8
⊢ ((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) → ((𝑃 ∨ 𝑄) ≤ (𝑟 ∨ 𝑠) ↔ (𝑃 ∨ 𝑄) = (𝑟 ∨ 𝑠))) | 
| 44 | 38, 39, 40, 41, 42, 43 | syl131anc 1384 | . . . . . . 7
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → ((𝑃 ∨ 𝑄) ≤ (𝑟 ∨ 𝑠) ↔ (𝑃 ∨ 𝑄) = (𝑟 ∨ 𝑠))) | 
| 45 | 44 | biimpd 229 | . . . . . 6
⊢ (((𝐾 ∈ HL ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴)) ∧ 𝑃 ≠ 𝑄) → ((𝑃 ∨ 𝑄) ≤ (𝑟 ∨ 𝑠) → (𝑃 ∨ 𝑄) = (𝑟 ∨ 𝑠))) | 
| 46 | 21, 37, 45 | sylc 65 | . . . . 5
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → (𝑃 ∨ 𝑄) = (𝑟 ∨ 𝑠)) | 
| 47 | 13, 46 | eqtr4d 2779 | . . . 4
⊢ ((((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) ∧ (𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠))) → 𝑋 = (𝑃 ∨ 𝑄)) | 
| 48 | 47 | 3exp 1119 | . . 3
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → ((𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) → ((𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠)) → 𝑋 = (𝑃 ∨ 𝑄)))) | 
| 49 | 48 | rexlimdvv 3211 | . 2
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → (∃𝑟 ∈ 𝐴 ∃𝑠 ∈ 𝐴 (𝑟 ≠ 𝑠 ∧ 𝑋 = (𝑟 ∨ 𝑠)) → 𝑋 = (𝑃 ∨ 𝑄))) | 
| 50 | 12, 49 | mpd 15 | 1
⊢ (((𝐾 ∈ HL ∧ 𝑋 ∈ 𝐵 ∧ (𝑀‘𝑋) ∈ 𝑁) ∧ (𝑃 ∈ 𝐴 ∧ 𝑄 ∈ 𝐴 ∧ 𝑃 ≠ 𝑄) ∧ (𝑃 ≤ 𝑋 ∧ 𝑄 ≤ 𝑋)) → 𝑋 = (𝑃 ∨ 𝑄)) |