| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mdslmd.1 | ⊢ 𝐴  ∈   Cℋ | 
						
							| 2 |  | mdslmd.2 | ⊢ 𝐵  ∈   Cℋ | 
						
							| 3 |  | mdslmd.3 | ⊢ 𝐶  ∈   Cℋ | 
						
							| 4 |  | mdslmd.4 | ⊢ 𝐷  ∈   Cℋ | 
						
							| 5 |  | mddmd | ⊢ ( ( 𝐴  ∈   Cℋ   ∧  𝐵  ∈   Cℋ  )  →  ( 𝐴  𝑀ℋ  𝐵  ↔  ( ⊥ ‘ 𝐴 )  𝑀ℋ*  ( ⊥ ‘ 𝐵 ) ) ) | 
						
							| 6 | 1 2 5 | mp2an | ⊢ ( 𝐴  𝑀ℋ  𝐵  ↔  ( ⊥ ‘ 𝐴 )  𝑀ℋ*  ( ⊥ ‘ 𝐵 ) ) | 
						
							| 7 |  | dmdmd | ⊢ ( ( 𝐵  ∈   Cℋ   ∧  𝐴  ∈   Cℋ  )  →  ( 𝐵  𝑀ℋ*  𝐴  ↔  ( ⊥ ‘ 𝐵 )  𝑀ℋ  ( ⊥ ‘ 𝐴 ) ) ) | 
						
							| 8 | 2 1 7 | mp2an | ⊢ ( 𝐵  𝑀ℋ*  𝐴  ↔  ( ⊥ ‘ 𝐵 )  𝑀ℋ  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 9 | 6 8 | anbi12ci | ⊢ ( ( 𝐴  𝑀ℋ  𝐵  ∧  𝐵  𝑀ℋ*  𝐴 )  ↔  ( ( ⊥ ‘ 𝐵 )  𝑀ℋ  ( ⊥ ‘ 𝐴 )  ∧  ( ⊥ ‘ 𝐴 )  𝑀ℋ*  ( ⊥ ‘ 𝐵 ) ) ) | 
						
							| 10 | 3 4 | chincli | ⊢ ( 𝐶  ∩  𝐷 )  ∈   Cℋ | 
						
							| 11 | 1 10 | chsscon3i | ⊢ ( 𝐴  ⊆  ( 𝐶  ∩  𝐷 )  ↔  ( ⊥ ‘ ( 𝐶  ∩  𝐷 ) )  ⊆  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 12 | 3 4 | chdmm1i | ⊢ ( ⊥ ‘ ( 𝐶  ∩  𝐷 ) )  =  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐷 ) ) | 
						
							| 13 | 12 | sseq1i | ⊢ ( ( ⊥ ‘ ( 𝐶  ∩  𝐷 ) )  ⊆  ( ⊥ ‘ 𝐴 )  ↔  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐷 ) )  ⊆  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 14 | 11 13 | bitri | ⊢ ( 𝐴  ⊆  ( 𝐶  ∩  𝐷 )  ↔  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐷 ) )  ⊆  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 15 | 3 4 | chjcli | ⊢ ( 𝐶  ∨ℋ  𝐷 )  ∈   Cℋ | 
						
							| 16 | 1 2 | chjcli | ⊢ ( 𝐴  ∨ℋ  𝐵 )  ∈   Cℋ | 
						
							| 17 | 15 16 | chsscon3i | ⊢ ( ( 𝐶  ∨ℋ  𝐷 )  ⊆  ( 𝐴  ∨ℋ  𝐵 )  ↔  ( ⊥ ‘ ( 𝐴  ∨ℋ  𝐵 ) )  ⊆  ( ⊥ ‘ ( 𝐶  ∨ℋ  𝐷 ) ) ) | 
						
							| 18 | 1 2 | chdmj1i | ⊢ ( ⊥ ‘ ( 𝐴  ∨ℋ  𝐵 ) )  =  ( ( ⊥ ‘ 𝐴 )  ∩  ( ⊥ ‘ 𝐵 ) ) | 
						
							| 19 |  | incom | ⊢ ( ( ⊥ ‘ 𝐴 )  ∩  ( ⊥ ‘ 𝐵 ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 20 | 18 19 | eqtri | ⊢ ( ⊥ ‘ ( 𝐴  ∨ℋ  𝐵 ) )  =  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) ) | 
						
							| 21 | 3 4 | chdmj1i | ⊢ ( ⊥ ‘ ( 𝐶  ∨ℋ  𝐷 ) )  =  ( ( ⊥ ‘ 𝐶 )  ∩  ( ⊥ ‘ 𝐷 ) ) | 
						
							| 22 | 20 21 | sseq12i | ⊢ ( ( ⊥ ‘ ( 𝐴  ∨ℋ  𝐵 ) )  ⊆  ( ⊥ ‘ ( 𝐶  ∨ℋ  𝐷 ) )  ↔  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) )  ⊆  ( ( ⊥ ‘ 𝐶 )  ∩  ( ⊥ ‘ 𝐷 ) ) ) | 
						
							| 23 | 17 22 | bitri | ⊢ ( ( 𝐶  ∨ℋ  𝐷 )  ⊆  ( 𝐴  ∨ℋ  𝐵 )  ↔  ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) )  ⊆  ( ( ⊥ ‘ 𝐶 )  ∩  ( ⊥ ‘ 𝐷 ) ) ) | 
						
							| 24 | 14 23 | anbi12ci | ⊢ ( ( 𝐴  ⊆  ( 𝐶  ∩  𝐷 )  ∧  ( 𝐶  ∨ℋ  𝐷 )  ⊆  ( 𝐴  ∨ℋ  𝐵 ) )  ↔  ( ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) )  ⊆  ( ( ⊥ ‘ 𝐶 )  ∩  ( ⊥ ‘ 𝐷 ) )  ∧  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐷 ) )  ⊆  ( ⊥ ‘ 𝐴 ) ) ) | 
						
							| 25 | 2 | choccli | ⊢ ( ⊥ ‘ 𝐵 )  ∈   Cℋ | 
						
							| 26 | 1 | choccli | ⊢ ( ⊥ ‘ 𝐴 )  ∈   Cℋ | 
						
							| 27 | 3 | choccli | ⊢ ( ⊥ ‘ 𝐶 )  ∈   Cℋ | 
						
							| 28 | 4 | choccli | ⊢ ( ⊥ ‘ 𝐷 )  ∈   Cℋ | 
						
							| 29 | 25 26 27 28 | mdslmd2i | ⊢ ( ( ( ( ⊥ ‘ 𝐵 )  𝑀ℋ  ( ⊥ ‘ 𝐴 )  ∧  ( ⊥ ‘ 𝐴 )  𝑀ℋ*  ( ⊥ ‘ 𝐵 ) )  ∧  ( ( ( ⊥ ‘ 𝐵 )  ∩  ( ⊥ ‘ 𝐴 ) )  ⊆  ( ( ⊥ ‘ 𝐶 )  ∩  ( ⊥ ‘ 𝐷 ) )  ∧  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐷 ) )  ⊆  ( ⊥ ‘ 𝐴 ) ) )  →  ( ( ⊥ ‘ 𝐶 )  𝑀ℋ  ( ⊥ ‘ 𝐷 )  ↔  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) )  𝑀ℋ  ( ( ⊥ ‘ 𝐷 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) ) ) ) | 
						
							| 30 | 9 24 29 | syl2anb | ⊢ ( ( ( 𝐴  𝑀ℋ  𝐵  ∧  𝐵  𝑀ℋ*  𝐴 )  ∧  ( 𝐴  ⊆  ( 𝐶  ∩  𝐷 )  ∧  ( 𝐶  ∨ℋ  𝐷 )  ⊆  ( 𝐴  ∨ℋ  𝐵 ) ) )  →  ( ( ⊥ ‘ 𝐶 )  𝑀ℋ  ( ⊥ ‘ 𝐷 )  ↔  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) )  𝑀ℋ  ( ( ⊥ ‘ 𝐷 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) ) ) ) | 
						
							| 31 |  | dmdmd | ⊢ ( ( 𝐶  ∈   Cℋ   ∧  𝐷  ∈   Cℋ  )  →  ( 𝐶  𝑀ℋ*  𝐷  ↔  ( ⊥ ‘ 𝐶 )  𝑀ℋ  ( ⊥ ‘ 𝐷 ) ) ) | 
						
							| 32 | 3 4 31 | mp2an | ⊢ ( 𝐶  𝑀ℋ*  𝐷  ↔  ( ⊥ ‘ 𝐶 )  𝑀ℋ  ( ⊥ ‘ 𝐷 ) ) | 
						
							| 33 | 3 2 | chincli | ⊢ ( 𝐶  ∩  𝐵 )  ∈   Cℋ | 
						
							| 34 | 4 2 | chincli | ⊢ ( 𝐷  ∩  𝐵 )  ∈   Cℋ | 
						
							| 35 |  | dmdmd | ⊢ ( ( ( 𝐶  ∩  𝐵 )  ∈   Cℋ   ∧  ( 𝐷  ∩  𝐵 )  ∈   Cℋ  )  →  ( ( 𝐶  ∩  𝐵 )  𝑀ℋ*  ( 𝐷  ∩  𝐵 )  ↔  ( ⊥ ‘ ( 𝐶  ∩  𝐵 ) )  𝑀ℋ  ( ⊥ ‘ ( 𝐷  ∩  𝐵 ) ) ) ) | 
						
							| 36 | 33 34 35 | mp2an | ⊢ ( ( 𝐶  ∩  𝐵 )  𝑀ℋ*  ( 𝐷  ∩  𝐵 )  ↔  ( ⊥ ‘ ( 𝐶  ∩  𝐵 ) )  𝑀ℋ  ( ⊥ ‘ ( 𝐷  ∩  𝐵 ) ) ) | 
						
							| 37 | 3 2 | chdmm1i | ⊢ ( ⊥ ‘ ( 𝐶  ∩  𝐵 ) )  =  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) ) | 
						
							| 38 | 4 2 | chdmm1i | ⊢ ( ⊥ ‘ ( 𝐷  ∩  𝐵 ) )  =  ( ( ⊥ ‘ 𝐷 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) ) | 
						
							| 39 | 37 38 | breq12i | ⊢ ( ( ⊥ ‘ ( 𝐶  ∩  𝐵 ) )  𝑀ℋ  ( ⊥ ‘ ( 𝐷  ∩  𝐵 ) )  ↔  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) )  𝑀ℋ  ( ( ⊥ ‘ 𝐷 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) ) ) | 
						
							| 40 | 36 39 | bitri | ⊢ ( ( 𝐶  ∩  𝐵 )  𝑀ℋ*  ( 𝐷  ∩  𝐵 )  ↔  ( ( ⊥ ‘ 𝐶 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) )  𝑀ℋ  ( ( ⊥ ‘ 𝐷 )  ∨ℋ  ( ⊥ ‘ 𝐵 ) ) ) | 
						
							| 41 | 30 32 40 | 3bitr4g | ⊢ ( ( ( 𝐴  𝑀ℋ  𝐵  ∧  𝐵  𝑀ℋ*  𝐴 )  ∧  ( 𝐴  ⊆  ( 𝐶  ∩  𝐷 )  ∧  ( 𝐶  ∨ℋ  𝐷 )  ⊆  ( 𝐴  ∨ℋ  𝐵 ) ) )  →  ( 𝐶  𝑀ℋ*  𝐷  ↔  ( 𝐶  ∩  𝐵 )  𝑀ℋ*  ( 𝐷  ∩  𝐵 ) ) ) |