| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							mdslle1.1 | 
							 |-  A e. CH  | 
						
						
							| 2 | 
							
								
							 | 
							mdslle1.2 | 
							 |-  B e. CH  | 
						
						
							| 3 | 
							
								
							 | 
							mdslle1.3 | 
							 |-  C e. CH  | 
						
						
							| 4 | 
							
								
							 | 
							mdslle1.4 | 
							 |-  D e. CH  | 
						
						
							| 5 | 
							
								
							 | 
							ssin | 
							 |-  ( ( A C_ C /\ A C_ D ) <-> A C_ ( C i^i D ) )  | 
						
						
							| 6 | 
							
								5
							 | 
							bicomi | 
							 |-  ( A C_ ( C i^i D ) <-> ( A C_ C /\ A C_ D ) )  | 
						
						
							| 7 | 
							
								1 2
							 | 
							chjcli | 
							 |-  ( A vH B ) e. CH  | 
						
						
							| 8 | 
							
								3 4 7
							 | 
							chlubi | 
							 |-  ( ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) <-> ( C vH D ) C_ ( A vH B ) )  | 
						
						
							| 9 | 
							
								8
							 | 
							bicomi | 
							 |-  ( ( C vH D ) C_ ( A vH B ) <-> ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) )  | 
						
						
							| 10 | 
							
								6 9
							 | 
							anbi12i | 
							 |-  ( ( A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) <-> ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) )  | 
						
						
							| 11 | 
							
								
							 | 
							simpr | 
							 |-  ( ( A MH B /\ B MH* A ) -> B MH* A )  | 
						
						
							| 12 | 
							
								
							 | 
							simpl | 
							 |-  ( ( A C_ C /\ A C_ D ) -> A C_ C )  | 
						
						
							| 13 | 
							
								
							 | 
							simpl | 
							 |-  ( ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) -> C C_ ( A vH B ) )  | 
						
						
							| 14 | 
							
								1 2 3
							 | 
							3pm3.2i | 
							 |-  ( A e. CH /\ B e. CH /\ C e. CH )  | 
						
						
							| 15 | 
							
								
							 | 
							dmdsl3 | 
							 |-  ( ( ( A e. CH /\ B e. CH /\ C e. CH ) /\ ( B MH* A /\ A C_ C /\ C C_ ( A vH B ) ) ) -> ( ( C i^i B ) vH A ) = C )  | 
						
						
							| 16 | 
							
								14 15
							 | 
							mpan | 
							 |-  ( ( B MH* A /\ A C_ C /\ C C_ ( A vH B ) ) -> ( ( C i^i B ) vH A ) = C )  | 
						
						
							| 17 | 
							
								11 12 13 16
							 | 
							syl3an | 
							 |-  ( ( ( 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 ) vH A ) = C )  | 
						
						
							| 18 | 
							
								3 2
							 | 
							chincli | 
							 |-  ( C i^i B ) e. CH  | 
						
						
							| 19 | 
							
								4 2
							 | 
							chincli | 
							 |-  ( D i^i B ) e. CH  | 
						
						
							| 20 | 
							
								18 19
							 | 
							chub1i | 
							 |-  ( C i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) )  | 
						
						
							| 21 | 
							
								18 19
							 | 
							chjcli | 
							 |-  ( ( C i^i B ) vH ( D i^i B ) ) e. CH  | 
						
						
							| 22 | 
							
								18 21 1
							 | 
							chlej1i | 
							 |-  ( ( C i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) -> ( ( C i^i B ) vH A ) C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 23 | 
							
								20 22
							 | 
							mp1i | 
							 |-  ( ( ( 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 ) vH A ) C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 24 | 
							
								17 23
							 | 
							eqsstrrd | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> C C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 25 | 
							
								
							 | 
							simpr | 
							 |-  ( ( A C_ C /\ A C_ D ) -> A C_ D )  | 
						
						
							| 26 | 
							
								
							 | 
							simpr | 
							 |-  ( ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) -> D C_ ( A vH B ) )  | 
						
						
							| 27 | 
							
								1 2 4
							 | 
							3pm3.2i | 
							 |-  ( A e. CH /\ B e. CH /\ D e. CH )  | 
						
						
							| 28 | 
							
								
							 | 
							dmdsl3 | 
							 |-  ( ( ( A e. CH /\ B e. CH /\ D e. CH ) /\ ( B MH* A /\ A C_ D /\ D C_ ( A vH B ) ) ) -> ( ( D i^i B ) vH A ) = D )  | 
						
						
							| 29 | 
							
								27 28
							 | 
							mpan | 
							 |-  ( ( B MH* A /\ A C_ D /\ D C_ ( A vH B ) ) -> ( ( D i^i B ) vH A ) = D )  | 
						
						
							| 30 | 
							
								11 25 26 29
							 | 
							syl3an | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> ( ( D i^i B ) vH A ) = D )  | 
						
						
							| 31 | 
							
								19 18
							 | 
							chub2i | 
							 |-  ( D i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) )  | 
						
						
							| 32 | 
							
								19 21 1
							 | 
							chlej1i | 
							 |-  ( ( D i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) -> ( ( D i^i B ) vH A ) C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 33 | 
							
								31 32
							 | 
							mp1i | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> ( ( D i^i B ) vH A ) C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 34 | 
							
								30 33
							 | 
							eqsstrrd | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> D C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 35 | 
							
								24 34
							 | 
							jca | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> ( C C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) /\ D C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) ) )  | 
						
						
							| 36 | 
							
								21 1
							 | 
							chjcli | 
							 |-  ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) e. CH  | 
						
						
							| 37 | 
							
								3 4 36
							 | 
							chlubi | 
							 |-  ( ( C C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) /\ D C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) ) <-> ( C vH D ) C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 38 | 
							
								35 37
							 | 
							sylib | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> ( C vH D ) C_ ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) )  | 
						
						
							| 39 | 
							
								38
							 | 
							ssrind | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> ( ( C vH D ) i^i B ) C_ ( ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) i^i B ) )  | 
						
						
							| 40 | 
							
								
							 | 
							simpl | 
							 |-  ( ( A MH B /\ B MH* A ) -> A MH B )  | 
						
						
							| 41 | 
							
								
							 | 
							ssrin | 
							 |-  ( A C_ C -> ( A i^i B ) C_ ( C i^i B ) )  | 
						
						
							| 42 | 
							
								41 20
							 | 
							sstrdi | 
							 |-  ( A C_ C -> ( A i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 43 | 
							
								42
							 | 
							adantr | 
							 |-  ( ( A C_ C /\ A C_ D ) -> ( A i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 44 | 
							
								
							 | 
							inss2 | 
							 |-  ( C i^i B ) C_ B  | 
						
						
							| 45 | 
							
								
							 | 
							inss2 | 
							 |-  ( D i^i B ) C_ B  | 
						
						
							| 46 | 
							
								18 19 2
							 | 
							chlubi | 
							 |-  ( ( ( C i^i B ) C_ B /\ ( D i^i B ) C_ B ) <-> ( ( C i^i B ) vH ( D i^i B ) ) C_ B )  | 
						
						
							| 47 | 
							
								46
							 | 
							bicomi | 
							 |-  ( ( ( C i^i B ) vH ( D i^i B ) ) C_ B <-> ( ( C i^i B ) C_ B /\ ( D i^i B ) C_ B ) )  | 
						
						
							| 48 | 
							
								44 45 47
							 | 
							mpbir2an | 
							 |-  ( ( C i^i B ) vH ( D i^i B ) ) C_ B  | 
						
						
							| 49 | 
							
								48
							 | 
							a1i | 
							 |-  ( ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) -> ( ( C i^i B ) vH ( D i^i B ) ) C_ B )  | 
						
						
							| 50 | 
							
								1 2 21
							 | 
							3pm3.2i | 
							 |-  ( A e. CH /\ B e. CH /\ ( ( C i^i B ) vH ( D i^i B ) ) e. CH )  | 
						
						
							| 51 | 
							
								
							 | 
							mdsl3 | 
							 |-  ( ( ( A e. CH /\ B e. CH /\ ( ( C i^i B ) vH ( D i^i B ) ) e. CH ) /\ ( A MH B /\ ( A i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) /\ ( ( C i^i B ) vH ( D i^i B ) ) C_ B ) ) -> ( ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) i^i B ) = ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 52 | 
							
								50 51
							 | 
							mpan | 
							 |-  ( ( A MH B /\ ( A i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) /\ ( ( C i^i B ) vH ( D i^i B ) ) C_ B ) -> ( ( ( ( C i^i B ) vH ( D i^i B ) ) vH A ) i^i B ) = ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 53 | 
							
								40 43 49 52
							 | 
							syl3an | 
							 |-  ( ( ( 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 ) vH ( D i^i B ) ) vH A ) i^i B ) = ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 54 | 
							
								39 53
							 | 
							sseqtrd | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) -> ( ( C vH D ) i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 55 | 
							
								54
							 | 
							3expb | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( ( A C_ C /\ A C_ D ) /\ ( C C_ ( A vH B ) /\ D C_ ( A vH B ) ) ) ) -> ( ( C vH D ) i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 56 | 
							
								10 55
							 | 
							sylan2b | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) ) -> ( ( C vH D ) i^i B ) C_ ( ( C i^i B ) vH ( D i^i B ) ) )  | 
						
						
							| 57 | 
							
								3 4 2
							 | 
							lediri | 
							 |-  ( ( C i^i B ) vH ( D i^i B ) ) C_ ( ( C vH D ) i^i B )  | 
						
						
							| 58 | 
							
								57
							 | 
							a1i | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) ) -> ( ( C i^i B ) vH ( D i^i B ) ) C_ ( ( C vH D ) i^i B ) )  | 
						
						
							| 59 | 
							
								56 58
							 | 
							eqssd | 
							 |-  ( ( ( A MH B /\ B MH* A ) /\ ( A C_ ( C i^i D ) /\ ( C vH D ) C_ ( A vH B ) ) ) -> ( ( C vH D ) i^i B ) = ( ( C i^i B ) vH ( D i^i B ) ) )  |