| Step | Hyp | Ref | Expression | 
						
							| 1 |  | latdisd.b | ⊢ 𝐵  =  ( Base ‘ 𝐾 ) | 
						
							| 2 |  | latdisd.j | ⊢  ∨   =  ( join ‘ 𝐾 ) | 
						
							| 3 |  | latdisd.m | ⊢  ∧   =  ( meet ‘ 𝐾 ) | 
						
							| 4 | 1 3 | latmcl | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  →  ( 𝑥  ∧  𝑦 )  ∈  𝐵 ) | 
						
							| 5 | 4 | 3adant3r3 | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∧  𝑦 )  ∈  𝐵 ) | 
						
							| 6 |  | simpr1 | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  𝑥  ∈  𝐵 ) | 
						
							| 7 |  | simpr3 | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  𝑧  ∈  𝐵 ) | 
						
							| 8 |  | oveq1 | ⊢ ( 𝑢  =  ( 𝑥  ∧  𝑦 )  →  ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑣  ∧  𝑤 ) ) ) | 
						
							| 9 |  | oveq1 | ⊢ ( 𝑢  =  ( 𝑥  ∧  𝑦 )  →  ( 𝑢  ∨  𝑣 )  =  ( ( 𝑥  ∧  𝑦 )  ∨  𝑣 ) ) | 
						
							| 10 |  | oveq1 | ⊢ ( 𝑢  =  ( 𝑥  ∧  𝑦 )  →  ( 𝑢  ∨  𝑤 )  =  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) ) | 
						
							| 11 | 9 10 | oveq12d | ⊢ ( 𝑢  =  ( 𝑥  ∧  𝑦 )  →  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑣 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) ) ) | 
						
							| 12 | 8 11 | eqeq12d | ⊢ ( 𝑢  =  ( 𝑥  ∧  𝑦 )  →  ( ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  ↔  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑣 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) ) ) ) | 
						
							| 13 |  | oveq1 | ⊢ ( 𝑣  =  𝑥  →  ( 𝑣  ∧  𝑤 )  =  ( 𝑥  ∧  𝑤 ) ) | 
						
							| 14 | 13 | oveq2d | ⊢ ( 𝑣  =  𝑥  →  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑤 ) ) ) | 
						
							| 15 |  | oveq2 | ⊢ ( 𝑣  =  𝑥  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑣 )  =  ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 ) ) | 
						
							| 16 | 15 | oveq1d | ⊢ ( 𝑣  =  𝑥  →  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑣 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) ) ) | 
						
							| 17 | 14 16 | eqeq12d | ⊢ ( 𝑣  =  𝑥  →  ( ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑣 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) )  ↔  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) ) ) ) | 
						
							| 18 |  | oveq2 | ⊢ ( 𝑤  =  𝑧  →  ( 𝑥  ∧  𝑤 )  =  ( 𝑥  ∧  𝑧 ) ) | 
						
							| 19 | 18 | oveq2d | ⊢ ( 𝑤  =  𝑧  →  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑤 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) ) ) | 
						
							| 20 |  | oveq2 | ⊢ ( 𝑤  =  𝑧  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 )  =  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) ) | 
						
							| 21 | 20 | oveq2d | ⊢ ( 𝑤  =  𝑧  →  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) ) ) | 
						
							| 22 | 19 21 | eqeq12d | ⊢ ( 𝑤  =  𝑧  →  ( ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑤 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑤 ) )  ↔  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) ) ) ) | 
						
							| 23 | 12 17 22 | rspc3v | ⊢ ( ( ( 𝑥  ∧  𝑦 )  ∈  𝐵  ∧  𝑥  ∈  𝐵  ∧  𝑧  ∈  𝐵 )  →  ( ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  →  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) ) ) ) | 
						
							| 24 | 5 6 7 23 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  →  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) ) ) ) | 
						
							| 25 | 24 | imp | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) )  =  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) ) ) | 
						
							| 26 |  | simpl | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  𝐾  ∈  Lat ) | 
						
							| 27 | 1 2 | latjcom | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∧  𝑦 )  ∈  𝐵  ∧  𝑥  ∈  𝐵 )  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  =  ( 𝑥  ∨  ( 𝑥  ∧  𝑦 ) ) ) | 
						
							| 28 | 26 5 6 27 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  =  ( 𝑥  ∨  ( 𝑥  ∧  𝑦 ) ) ) | 
						
							| 29 | 1 2 3 | latabs1 | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  →  ( 𝑥  ∨  ( 𝑥  ∧  𝑦 ) )  =  𝑥 ) | 
						
							| 30 | 29 | 3adant3r3 | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∨  ( 𝑥  ∧  𝑦 ) )  =  𝑥 ) | 
						
							| 31 | 28 30 | eqtrd | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  =  𝑥 ) | 
						
							| 32 | 1 2 | latjcom | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∧  𝑦 )  ∈  𝐵  ∧  𝑧  ∈  𝐵 )  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 )  =  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) ) | 
						
							| 33 | 26 5 7 32 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 )  =  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) ) | 
						
							| 34 | 31 33 | oveq12d | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) )  =  ( 𝑥  ∧  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) ) ) | 
						
							| 35 | 34 | adantr | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( ( ( 𝑥  ∧  𝑦 )  ∨  𝑥 )  ∧  ( ( 𝑥  ∧  𝑦 )  ∨  𝑧 ) )  =  ( 𝑥  ∧  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) ) ) | 
						
							| 36 |  | simpr2 | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  𝑦  ∈  𝐵 ) | 
						
							| 37 |  | oveq1 | ⊢ ( 𝑢  =  𝑧  →  ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( 𝑧  ∨  ( 𝑣  ∧  𝑤 ) ) ) | 
						
							| 38 |  | oveq1 | ⊢ ( 𝑢  =  𝑧  →  ( 𝑢  ∨  𝑣 )  =  ( 𝑧  ∨  𝑣 ) ) | 
						
							| 39 |  | oveq1 | ⊢ ( 𝑢  =  𝑧  →  ( 𝑢  ∨  𝑤 )  =  ( 𝑧  ∨  𝑤 ) ) | 
						
							| 40 | 38 39 | oveq12d | ⊢ ( 𝑢  =  𝑧  →  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  =  ( ( 𝑧  ∨  𝑣 )  ∧  ( 𝑧  ∨  𝑤 ) ) ) | 
						
							| 41 | 37 40 | eqeq12d | ⊢ ( 𝑢  =  𝑧  →  ( ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  ↔  ( 𝑧  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑧  ∨  𝑣 )  ∧  ( 𝑧  ∨  𝑤 ) ) ) ) | 
						
							| 42 | 13 | oveq2d | ⊢ ( 𝑣  =  𝑥  →  ( 𝑧  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( 𝑧  ∨  ( 𝑥  ∧  𝑤 ) ) ) | 
						
							| 43 |  | oveq2 | ⊢ ( 𝑣  =  𝑥  →  ( 𝑧  ∨  𝑣 )  =  ( 𝑧  ∨  𝑥 ) ) | 
						
							| 44 | 43 | oveq1d | ⊢ ( 𝑣  =  𝑥  →  ( ( 𝑧  ∨  𝑣 )  ∧  ( 𝑧  ∨  𝑤 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑤 ) ) ) | 
						
							| 45 | 42 44 | eqeq12d | ⊢ ( 𝑣  =  𝑥  →  ( ( 𝑧  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑧  ∨  𝑣 )  ∧  ( 𝑧  ∨  𝑤 ) )  ↔  ( 𝑧  ∨  ( 𝑥  ∧  𝑤 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑤 ) ) ) ) | 
						
							| 46 |  | oveq2 | ⊢ ( 𝑤  =  𝑦  →  ( 𝑥  ∧  𝑤 )  =  ( 𝑥  ∧  𝑦 ) ) | 
						
							| 47 | 46 | oveq2d | ⊢ ( 𝑤  =  𝑦  →  ( 𝑧  ∨  ( 𝑥  ∧  𝑤 ) )  =  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) ) | 
						
							| 48 |  | oveq2 | ⊢ ( 𝑤  =  𝑦  →  ( 𝑧  ∨  𝑤 )  =  ( 𝑧  ∨  𝑦 ) ) | 
						
							| 49 | 48 | oveq2d | ⊢ ( 𝑤  =  𝑦  →  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑤 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) | 
						
							| 50 | 47 49 | eqeq12d | ⊢ ( 𝑤  =  𝑦  →  ( ( 𝑧  ∨  ( 𝑥  ∧  𝑤 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑤 ) )  ↔  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) ) | 
						
							| 51 | 41 45 50 | rspc3v | ⊢ ( ( 𝑧  ∈  𝐵  ∧  𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  →  ( ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  →  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) ) | 
						
							| 52 | 7 6 36 51 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  →  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) ) | 
						
							| 53 | 52 | imp | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) )  =  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) | 
						
							| 54 | 53 | oveq2d | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( 𝑥  ∧  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) )  =  ( 𝑥  ∧  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) ) | 
						
							| 55 | 1 2 | latjcl | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑧  ∈  𝐵  ∧  𝑥  ∈  𝐵 )  →  ( 𝑧  ∨  𝑥 )  ∈  𝐵 ) | 
						
							| 56 | 26 7 6 55 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑧  ∨  𝑥 )  ∈  𝐵 ) | 
						
							| 57 | 1 2 | latjcl | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑧  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  →  ( 𝑧  ∨  𝑦 )  ∈  𝐵 ) | 
						
							| 58 | 26 7 36 57 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑧  ∨  𝑦 )  ∈  𝐵 ) | 
						
							| 59 | 1 3 | latmass | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  ( 𝑧  ∨  𝑥 )  ∈  𝐵  ∧  ( 𝑧  ∨  𝑦 )  ∈  𝐵 ) )  →  ( ( 𝑥  ∧  ( 𝑧  ∨  𝑥 ) )  ∧  ( 𝑧  ∨  𝑦 ) )  =  ( 𝑥  ∧  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) ) | 
						
							| 60 | 26 6 56 58 59 | syl13anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ( 𝑥  ∧  ( 𝑧  ∨  𝑥 ) )  ∧  ( 𝑧  ∨  𝑦 ) )  =  ( 𝑥  ∧  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) ) ) | 
						
							| 61 | 1 2 | latjcom | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑧  ∈  𝐵  ∧  𝑥  ∈  𝐵 )  →  ( 𝑧  ∨  𝑥 )  =  ( 𝑥  ∨  𝑧 ) ) | 
						
							| 62 | 26 7 6 61 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑧  ∨  𝑥 )  =  ( 𝑥  ∨  𝑧 ) ) | 
						
							| 63 | 62 | oveq2d | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∧  ( 𝑧  ∨  𝑥 ) )  =  ( 𝑥  ∧  ( 𝑥  ∨  𝑧 ) ) ) | 
						
							| 64 | 1 2 3 | latabs2 | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑥  ∈  𝐵  ∧  𝑧  ∈  𝐵 )  →  ( 𝑥  ∧  ( 𝑥  ∨  𝑧 ) )  =  𝑥 ) | 
						
							| 65 | 26 6 7 64 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∧  ( 𝑥  ∨  𝑧 ) )  =  𝑥 ) | 
						
							| 66 | 63 65 | eqtrd | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∧  ( 𝑧  ∨  𝑥 ) )  =  𝑥 ) | 
						
							| 67 | 1 2 | latjcom | ⊢ ( ( 𝐾  ∈  Lat  ∧  𝑧  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  →  ( 𝑧  ∨  𝑦 )  =  ( 𝑦  ∨  𝑧 ) ) | 
						
							| 68 | 26 7 36 67 | syl3anc | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑧  ∨  𝑦 )  =  ( 𝑦  ∨  𝑧 ) ) | 
						
							| 69 | 66 68 | oveq12d | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( ( 𝑥  ∧  ( 𝑧  ∨  𝑥 ) )  ∧  ( 𝑧  ∨  𝑦 ) )  =  ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) ) ) | 
						
							| 70 | 60 69 | eqtr3d | ⊢ ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∧  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) )  =  ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) ) ) | 
						
							| 71 | 70 | adantr | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( 𝑥  ∧  ( ( 𝑧  ∨  𝑥 )  ∧  ( 𝑧  ∨  𝑦 ) ) )  =  ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) ) ) | 
						
							| 72 | 54 71 | eqtrd | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( 𝑥  ∧  ( 𝑧  ∨  ( 𝑥  ∧  𝑦 ) ) )  =  ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) ) ) | 
						
							| 73 | 25 35 72 | 3eqtrrd | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) ) ) | 
						
							| 74 | 73 | an32s | ⊢ ( ( ( 𝐾  ∈  Lat  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  ∧  ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵  ∧  𝑧  ∈  𝐵 ) )  →  ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) ) ) | 
						
							| 75 | 74 | ralrimivvva | ⊢ ( ( 𝐾  ∈  Lat  ∧  ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) ) )  →  ∀ 𝑥  ∈  𝐵 ∀ 𝑦  ∈  𝐵 ∀ 𝑧  ∈  𝐵 ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) ) ) | 
						
							| 76 | 75 | ex | ⊢ ( 𝐾  ∈  Lat  →  ( ∀ 𝑢  ∈  𝐵 ∀ 𝑣  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( 𝑢  ∨  ( 𝑣  ∧  𝑤 ) )  =  ( ( 𝑢  ∨  𝑣 )  ∧  ( 𝑢  ∨  𝑤 ) )  →  ∀ 𝑥  ∈  𝐵 ∀ 𝑦  ∈  𝐵 ∀ 𝑧  ∈  𝐵 ( 𝑥  ∧  ( 𝑦  ∨  𝑧 ) )  =  ( ( 𝑥  ∧  𝑦 )  ∨  ( 𝑥  ∧  𝑧 ) ) ) ) |