| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mdslmd.1 |  |-  A e. CH | 
						
							| 2 |  | mdslmd.2 |  |-  B e. CH | 
						
							| 3 |  | mdslmd.3 |  |-  C e. CH | 
						
							| 4 |  | mdslmd.4 |  |-  D e. CH | 
						
							| 5 |  | ssin |  |-  ( ( A C_ C /\ A C_ D ) <-> A C_ ( C i^i D ) ) | 
						
							| 6 | 1 2 | chjcli |  |-  ( A vH B ) e. CH | 
						
							| 7 | 3 4 6 | chlubi |  |-  ( ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) <-> ( C vH D ) C_ ( A vH B ) ) | 
						
							| 8 | 5 7 | anbi12i |  |-  ( ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) <-> ( A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) ) | 
						
							| 9 |  | chjcl |  |-  ( ( x e. CH /\ A e. CH ) -> ( x vH A ) e. CH ) | 
						
							| 10 | 1 9 | mpan2 |  |-  ( x e. CH -> ( x vH A ) e. CH ) | 
						
							| 11 |  | sseq1 |  |-  ( y = ( x vH A ) -> ( y C_ D <-> ( x vH A ) C_ D ) ) | 
						
							| 12 |  | oveq1 |  |-  ( y = ( x vH A ) -> ( y vH C ) = ( ( x vH A ) vH C ) ) | 
						
							| 13 | 12 | ineq1d |  |-  ( y = ( x vH A ) -> ( ( y vH C ) i^i D ) = ( ( ( x vH A ) vH C ) i^i D ) ) | 
						
							| 14 |  | oveq1 |  |-  ( y = ( x vH A ) -> ( y vH ( C i^i D ) ) = ( ( x vH A ) vH ( C i^i D ) ) ) | 
						
							| 15 | 13 14 | sseq12d |  |-  ( y = ( x vH A ) -> ( ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) <-> ( ( ( x vH A ) vH C ) i^i D ) C_ ( ( x vH A ) vH ( C i^i D ) ) ) ) | 
						
							| 16 | 11 15 | imbi12d |  |-  ( y = ( x vH A ) -> ( ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) <-> ( ( x vH A ) C_ D -> ( ( ( x vH A ) vH C ) i^i D ) C_ ( ( x vH A ) vH ( C i^i D ) ) ) ) ) | 
						
							| 17 | 16 | rspcv |  |-  ( ( x vH A ) e. CH -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> ( ( x vH A ) C_ D -> ( ( ( x vH A ) vH C ) i^i D ) C_ ( ( x vH A ) vH ( C i^i D ) ) ) ) ) | 
						
							| 18 | 10 17 | syl |  |-  ( x e. CH -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> ( ( x vH A ) C_ D -> ( ( ( x vH A ) vH C ) i^i D ) C_ ( ( x vH A ) vH ( C i^i D ) ) ) ) ) | 
						
							| 19 | 18 | adantr |  |-  ( ( x e. CH /\ ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) ) -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> ( ( x vH A ) C_ D -> ( ( ( x vH A ) vH C ) i^i D ) C_ ( ( x vH A ) vH ( C i^i D ) ) ) ) ) | 
						
							| 20 | 1 2 3 4 | mdslmd1lem3 |  |-  ( ( x e. CH /\ ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) ) -> ( ( ( x vH A ) C_ D -> ( ( ( x vH A ) vH C ) i^i D ) C_ ( ( x vH A ) vH ( C i^i D ) ) ) -> ( ( ( ( C i^i B ) i^i ( D i^i B ) ) C_ x /\ x C_ ( D i^i B ) ) -> ( ( x vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( x vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 21 | 19 20 | syld |  |-  ( ( x e. CH /\ ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) ) -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> ( ( ( ( C i^i B ) i^i ( D i^i B ) ) C_ x /\ x C_ ( D i^i B ) ) -> ( ( x vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( x vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 22 | 21 | ex |  |-  ( x e. CH -> ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> ( ( ( ( C i^i B ) i^i ( D i^i B ) ) C_ x /\ x C_ ( D i^i B ) ) -> ( ( x vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( x vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) ) | 
						
							| 23 | 22 | com3l |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> ( x e. CH -> ( ( ( ( C i^i B ) i^i ( D i^i B ) ) C_ x /\ x C_ ( D i^i B ) ) -> ( ( x vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( x vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) ) | 
						
							| 24 | 23 | ralrimdv |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) -> A. x e. CH ( ( ( ( C i^i B ) i^i ( D i^i B ) ) C_ x /\ x C_ ( D i^i B ) ) -> ( ( x vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( x vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 25 |  | mdbr2 |  |-  ( ( C e. CH /\ D e. CH ) -> ( C MH D <-> A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) ) ) | 
						
							| 26 | 3 4 25 | mp2an |  |-  ( C MH D <-> A. y e. CH ( y C_ D -> ( ( y vH C ) i^i D ) C_ ( y vH ( C i^i D ) ) ) ) | 
						
							| 27 | 3 2 | chincli |  |-  ( C i^i B ) e. CH | 
						
							| 28 | 4 2 | chincli |  |-  ( D i^i B ) e. CH | 
						
							| 29 | 27 28 | mdsl2i |  |-  ( ( C i^i B ) MH ( D i^i B ) <-> A. x e. CH ( ( ( ( C i^i B ) i^i ( D i^i B ) ) C_ x /\ x C_ ( D i^i B ) ) -> ( ( x vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( x vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) | 
						
							| 30 | 24 26 29 | 3imtr4g |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( C MH D -> ( C i^i B ) MH ( D i^i B ) ) ) | 
						
							| 31 |  | chincl |  |-  ( ( x e. CH /\ B e. CH ) -> ( x i^i B ) e. CH ) | 
						
							| 32 | 2 31 | mpan2 |  |-  ( x e. CH -> ( x i^i B ) e. CH ) | 
						
							| 33 |  | sseq1 |  |-  ( y = ( x i^i B ) -> ( y C_ ( D i^i B ) <-> ( x i^i B ) C_ ( D i^i B ) ) ) | 
						
							| 34 |  | oveq1 |  |-  ( y = ( x i^i B ) -> ( y vH ( C i^i B ) ) = ( ( x i^i B ) vH ( C i^i B ) ) ) | 
						
							| 35 | 34 | ineq1d |  |-  ( y = ( x i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) = ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) ) | 
						
							| 36 |  | oveq1 |  |-  ( y = ( x i^i B ) -> ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) = ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) | 
						
							| 37 | 35 36 | sseq12d |  |-  ( y = ( x i^i B ) -> ( ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) <-> ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) | 
						
							| 38 | 33 37 | imbi12d |  |-  ( y = ( x i^i B ) -> ( ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) <-> ( ( x i^i B ) C_ ( D i^i B ) -> ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 39 | 38 | rspcv |  |-  ( ( x i^i B ) e. CH -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( ( x i^i B ) C_ ( D i^i B ) -> ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 40 | 32 39 | syl |  |-  ( x e. CH -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( ( x i^i B ) C_ ( D i^i B ) -> ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 41 | 40 | adantr |  |-  ( ( x e. CH /\ ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) ) -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( ( x i^i B ) C_ ( D i^i B ) -> ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 42 | 1 2 3 4 | mdslmd1lem4 |  |-  ( ( x e. CH /\ ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) ) -> ( ( ( x i^i B ) C_ ( D i^i B ) -> ( ( ( x i^i B ) vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( ( x i^i B ) vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( ( ( C i^i D ) C_ x /\ x C_ D ) -> ( ( x vH C ) i^i D ) C_ ( x vH ( C i^i D ) ) ) ) ) | 
						
							| 43 | 41 42 | syld |  |-  ( ( x e. CH /\ ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) ) -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( ( ( C i^i D ) C_ x /\ x C_ D ) -> ( ( x vH C ) i^i D ) C_ ( x vH ( C i^i D ) ) ) ) ) | 
						
							| 44 | 43 | ex |  |-  ( x e. CH -> ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( ( ( C i^i D ) C_ x /\ x C_ D ) -> ( ( x vH C ) i^i D ) C_ ( x vH ( C i^i D ) ) ) ) ) ) | 
						
							| 45 | 44 | com3l |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> ( x e. CH -> ( ( ( C i^i D ) C_ x /\ x C_ D ) -> ( ( x vH C ) i^i D ) C_ ( x vH ( C i^i D ) ) ) ) ) ) | 
						
							| 46 | 45 | ralrimdv |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) -> A. x e. CH ( ( ( C i^i D ) C_ x /\ x C_ D ) -> ( ( x vH C ) i^i D ) C_ ( x vH ( C i^i D ) ) ) ) ) | 
						
							| 47 |  | mdbr2 |  |-  ( ( ( C i^i B ) e. CH /\ ( D i^i B ) e. CH ) -> ( ( C i^i B ) MH ( D i^i B ) <-> A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) ) | 
						
							| 48 | 27 28 47 | mp2an |  |-  ( ( C i^i B ) MH ( D i^i B ) <-> A. y e. CH ( y C_ ( D i^i B ) -> ( ( y vH ( C i^i B ) ) i^i ( D i^i B ) ) C_ ( y vH ( ( C i^i B ) i^i ( D i^i B ) ) ) ) ) | 
						
							| 49 | 3 4 | mdsl2i |  |-  ( C MH D <-> A. x e. CH ( ( ( C i^i D ) C_ x /\ x C_ D ) -> ( ( x vH C ) i^i D ) C_ ( x vH ( C i^i D ) ) ) ) | 
						
							| 50 | 46 48 49 | 3imtr4g |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( ( C i^i B ) MH ( D i^i B ) -> C MH D ) ) | 
						
							| 51 | 30 50 | impbid |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( C MH D <-> ( C i^i B ) MH ( D i^i B ) ) ) | 
						
							| 52 | 8 51 | sylan2br |  |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) ) -> ( C MH D <-> ( C i^i B ) MH ( D i^i B ) ) ) |