| Step | Hyp | Ref | Expression | 
						
							| 1 |  | alral | ⊢ ( ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  →  ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 2 | 1 | alimi | ⊢ ( ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  →  ∀ 𝑥 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 3 |  | alral | ⊢ ( ∀ 𝑥 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  →  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 4 | 2 3 | syl | ⊢ ( ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  →  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 5 | 4 | ralimi | ⊢ ( ∀ 𝑧  ∈  𝐴 ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  →  ∀ 𝑧  ∈  𝐴 ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 6 |  | ralcom | ⊢ ( ∀ 𝑧  ∈  𝐴 ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ∀ 𝑥  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 7 |  | ralcom | ⊢ ( ∀ 𝑧  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 8 | 7 | ralbii | ⊢ ( ∀ 𝑥  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 9 | 6 8 | bitri | ⊢ ( ∀ 𝑧  ∈  𝐴 ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 10 | 5 9 | sylib | ⊢ ( ∀ 𝑧  ∈  𝐴 ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  →  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 11 |  | dftr2 | ⊢ ( Tr  𝑧  ↔  ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 12 | 11 | ralbii | ⊢ ( ∀ 𝑧  ∈  𝐴 Tr  𝑧  ↔  ∀ 𝑧  ∈  𝐴 ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 13 |  | df-po | ⊢ (  E   Po  𝐴  ↔  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ¬  𝑥  E  𝑥  ∧  ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 ) ) ) | 
						
							| 14 |  | epel | ⊢ ( 𝑥  E  𝑦  ↔  𝑥  ∈  𝑦 ) | 
						
							| 15 |  | epel | ⊢ ( 𝑦  E  𝑧  ↔  𝑦  ∈  𝑧 ) | 
						
							| 16 | 14 15 | anbi12i | ⊢ ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  ↔  ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 ) ) | 
						
							| 17 |  | epel | ⊢ ( 𝑥  E  𝑧  ↔  𝑥  ∈  𝑧 ) | 
						
							| 18 | 16 17 | imbi12i | ⊢ ( ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 )  ↔  ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 19 |  | elirrv | ⊢ ¬  𝑥  ∈  𝑥 | 
						
							| 20 |  | epel | ⊢ ( 𝑥  E  𝑥  ↔  𝑥  ∈  𝑥 ) | 
						
							| 21 | 19 20 | mtbir | ⊢ ¬  𝑥  E  𝑥 | 
						
							| 22 | 21 | biantrur | ⊢ ( ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 )  ↔  ( ¬  𝑥  E  𝑥  ∧  ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 ) ) ) | 
						
							| 23 | 18 22 | bitr3i | ⊢ ( ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ( ¬  𝑥  E  𝑥  ∧  ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 ) ) ) | 
						
							| 24 | 23 | ralbii | ⊢ ( ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ∀ 𝑧  ∈  𝐴 ( ¬  𝑥  E  𝑥  ∧  ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 ) ) ) | 
						
							| 25 | 24 | 2ralbii | ⊢ ( ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 )  ↔  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ¬  𝑥  E  𝑥  ∧  ( ( 𝑥  E  𝑦  ∧  𝑦  E  𝑧 )  →  𝑥  E  𝑧 ) ) ) | 
						
							| 26 | 13 25 | bitr4i | ⊢ (  E   Po  𝐴  ↔  ∀ 𝑥  ∈  𝐴 ∀ 𝑦  ∈  𝐴 ∀ 𝑧  ∈  𝐴 ( ( 𝑥  ∈  𝑦  ∧  𝑦  ∈  𝑧 )  →  𝑥  ∈  𝑧 ) ) | 
						
							| 27 | 10 12 26 | 3imtr4i | ⊢ ( ∀ 𝑧  ∈  𝐴 Tr  𝑧  →   E   Po  𝐴 ) |