| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mdsymlem1.1 |  |-  A e. CH | 
						
							| 2 |  | mdsymlem1.2 |  |-  B e. CH | 
						
							| 3 |  | mdsymlem1.3 |  |-  C = ( A vH p ) | 
						
							| 4 | 2 | hatomici |  |-  ( B =/= 0H -> E. r e. HAtoms r C_ B ) | 
						
							| 5 |  | simplll |  |-  ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ ( r e. HAtoms /\ r C_ B ) ) -> p e. HAtoms ) | 
						
							| 6 |  | atelch |  |-  ( p e. HAtoms -> p e. CH ) | 
						
							| 7 |  | atelch |  |-  ( r e. HAtoms -> r e. CH ) | 
						
							| 8 |  | chub1 |  |-  ( ( p e. CH /\ r e. CH ) -> p C_ ( p vH r ) ) | 
						
							| 9 | 6 7 8 | syl2an |  |-  ( ( p e. HAtoms /\ r e. HAtoms ) -> p C_ ( p vH r ) ) | 
						
							| 10 | 9 | adantlr |  |-  ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ r e. HAtoms ) -> p C_ ( p vH r ) ) | 
						
							| 11 | 10 | adantlr |  |-  ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ r e. HAtoms ) -> p C_ ( p vH r ) ) | 
						
							| 12 | 1 2 3 | mdsymlem1 |  |-  ( ( ( p e. CH /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) -> p C_ A ) | 
						
							| 13 | 6 12 | sylanl1 |  |-  ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) -> p C_ A ) | 
						
							| 14 | 13 | adantr |  |-  ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ r e. HAtoms ) -> p C_ A ) | 
						
							| 15 | 11 14 | jca |  |-  ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ r e. HAtoms ) -> ( p C_ ( p vH r ) /\ p C_ A ) ) | 
						
							| 16 | 15 | anim1i |  |-  ( ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ r e. HAtoms ) /\ r C_ B ) -> ( ( p C_ ( p vH r ) /\ p C_ A ) /\ r C_ B ) ) | 
						
							| 17 |  | anass |  |-  ( ( ( p C_ ( p vH r ) /\ p C_ A ) /\ r C_ B ) <-> ( p C_ ( p vH r ) /\ ( p C_ A /\ r C_ B ) ) ) | 
						
							| 18 | 16 17 | sylib |  |-  ( ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ r e. HAtoms ) /\ r C_ B ) -> ( p C_ ( p vH r ) /\ ( p C_ A /\ r C_ B ) ) ) | 
						
							| 19 | 18 | anasss |  |-  ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ ( r e. HAtoms /\ r C_ B ) ) -> ( p C_ ( p vH r ) /\ ( p C_ A /\ r C_ B ) ) ) | 
						
							| 20 |  | oveq1 |  |-  ( q = p -> ( q vH r ) = ( p vH r ) ) | 
						
							| 21 | 20 | sseq2d |  |-  ( q = p -> ( p C_ ( q vH r ) <-> p C_ ( p vH r ) ) ) | 
						
							| 22 |  | sseq1 |  |-  ( q = p -> ( q C_ A <-> p C_ A ) ) | 
						
							| 23 | 22 | anbi1d |  |-  ( q = p -> ( ( q C_ A /\ r C_ B ) <-> ( p C_ A /\ r C_ B ) ) ) | 
						
							| 24 | 21 23 | anbi12d |  |-  ( q = p -> ( ( p C_ ( q vH r ) /\ ( q C_ A /\ r C_ B ) ) <-> ( p C_ ( p vH r ) /\ ( p C_ A /\ r C_ B ) ) ) ) | 
						
							| 25 | 24 | rspcev |  |-  ( ( p e. HAtoms /\ ( p C_ ( p vH r ) /\ ( p C_ A /\ r C_ B ) ) ) -> E. q e. HAtoms ( p C_ ( q vH r ) /\ ( q C_ A /\ r C_ B ) ) ) | 
						
							| 26 | 5 19 25 | syl2anc |  |-  ( ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) /\ ( r e. HAtoms /\ r C_ B ) ) -> E. q e. HAtoms ( p C_ ( q vH r ) /\ ( q C_ A /\ r C_ B ) ) ) | 
						
							| 27 | 26 | exp32 |  |-  ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) -> ( r e. HAtoms -> ( r C_ B -> E. q e. HAtoms ( p C_ ( q vH r ) /\ ( q C_ A /\ r C_ B ) ) ) ) ) | 
						
							| 28 | 27 | reximdvai |  |-  ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) -> ( E. r e. HAtoms r C_ B -> E. r e. HAtoms E. q e. HAtoms ( p C_ ( q vH r ) /\ ( q C_ A /\ r C_ B ) ) ) ) | 
						
							| 29 | 4 28 | syl5 |  |-  ( ( ( p e. HAtoms /\ ( B i^i C ) C_ A ) /\ ( B MH* A /\ p C_ ( A vH B ) ) ) -> ( B =/= 0H -> E. r e. HAtoms E. q e. HAtoms ( p C_ ( q vH r ) /\ ( q C_ A /\ r C_ B ) ) ) ) |