| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cvrat4.b | ⊢ 𝐵  =  ( Base ‘ 𝐾 ) | 
						
							| 2 |  | cvrat4.l | ⊢  ≤   =  ( le ‘ 𝐾 ) | 
						
							| 3 |  | cvrat4.j | ⊢  ∨   =  ( join ‘ 𝐾 ) | 
						
							| 4 |  | cvrat4.z | ⊢  0   =  ( 0. ‘ 𝐾 ) | 
						
							| 5 |  | cvrat4.a | ⊢ 𝐴  =  ( Atoms ‘ 𝐾 ) | 
						
							| 6 | 1 2 3 4 5 | cvrat4 | ⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  →  ( ( 𝑋  ≠   0   ∧  𝑃  ≤  ( 𝑋  ∨  𝑄 ) )  →  ∃ 𝑟  ∈  𝐴 ( 𝑟  ≤  𝑋  ∧  𝑃  ≤  ( 𝑄  ∨  𝑟 ) ) ) ) | 
						
							| 7 |  | hllat | ⊢ ( 𝐾  ∈  HL  →  𝐾  ∈  Lat ) | 
						
							| 8 | 7 | ad2antrr | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  𝐾  ∈  Lat ) | 
						
							| 9 |  | simplr3 | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  𝑄  ∈  𝐴 ) | 
						
							| 10 | 1 5 | atbase | ⊢ ( 𝑄  ∈  𝐴  →  𝑄  ∈  𝐵 ) | 
						
							| 11 | 9 10 | syl | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  𝑄  ∈  𝐵 ) | 
						
							| 12 | 1 5 | atbase | ⊢ ( 𝑟  ∈  𝐴  →  𝑟  ∈  𝐵 ) | 
						
							| 13 | 12 | adantl | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  𝑟  ∈  𝐵 ) | 
						
							| 14 | 1 3 | latjcom | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑄  ∈  𝐵  ∧  𝑟  ∈  𝐵 )  →  ( 𝑄  ∨  𝑟 )  =  ( 𝑟  ∨  𝑄 ) ) | 
						
							| 15 | 8 11 13 14 | syl3anc | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  ( 𝑄  ∨  𝑟 )  =  ( 𝑟  ∨  𝑄 ) ) | 
						
							| 16 | 15 | breq2d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  ( 𝑃  ≤  ( 𝑄  ∨  𝑟 )  ↔  𝑃  ≤  ( 𝑟  ∨  𝑄 ) ) ) | 
						
							| 17 | 16 | anbi2d | ⊢ ( ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  ∧  𝑟  ∈  𝐴 )  →  ( ( 𝑟  ≤  𝑋  ∧  𝑃  ≤  ( 𝑄  ∨  𝑟 ) )  ↔  ( 𝑟  ≤  𝑋  ∧  𝑃  ≤  ( 𝑟  ∨  𝑄 ) ) ) ) | 
						
							| 18 | 17 | rexbidva | ⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  →  ( ∃ 𝑟  ∈  𝐴 ( 𝑟  ≤  𝑋  ∧  𝑃  ≤  ( 𝑄  ∨  𝑟 ) )  ↔  ∃ 𝑟  ∈  𝐴 ( 𝑟  ≤  𝑋  ∧  𝑃  ≤  ( 𝑟  ∨  𝑄 ) ) ) ) | 
						
							| 19 | 6 18 | sylibd | ⊢ ( ( 𝐾  ∈  HL  ∧  ( 𝑋  ∈  𝐵  ∧  𝑃  ∈  𝐴  ∧  𝑄  ∈  𝐴 ) )  →  ( ( 𝑋  ≠   0   ∧  𝑃  ≤  ( 𝑋  ∨  𝑄 ) )  →  ∃ 𝑟  ∈  𝐴 ( 𝑟  ≤  𝑋  ∧  𝑃  ≤  ( 𝑟  ∨  𝑄 ) ) ) ) |