| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mptbi12f.1 | ⊢ Ⅎ 𝑥 𝐴 | 
						
							| 2 |  | mptbi12f.2 | ⊢ Ⅎ 𝑥 𝐵 | 
						
							| 3 | 1 2 | nfeq | ⊢ Ⅎ 𝑥 𝐴  =  𝐵 | 
						
							| 4 |  | eleq2 | ⊢ ( 𝐴  =  𝐵  →  ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) | 
						
							| 5 | 3 4 | alrimi | ⊢ ( 𝐴  =  𝐵  →  ∀ 𝑥 ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) | 
						
							| 6 |  | ax-5 | ⊢ ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  →  ∀ 𝑦 ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) | 
						
							| 7 | 5 6 | sylg | ⊢ ( 𝐴  =  𝐵  →  ∀ 𝑥 ∀ 𝑦 ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) | 
						
							| 8 |  | eqeq2 | ⊢ ( 𝐷  =  𝐸  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) | 
						
							| 9 | 8 | alrimiv | ⊢ ( 𝐷  =  𝐸  →  ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) | 
						
							| 10 | 9 | ralimi | ⊢ ( ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸  →  ∀ 𝑥  ∈  𝐴 ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) | 
						
							| 11 |  | df-ral | ⊢ ( ∀ 𝑥  ∈  𝐴 ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 )  ↔  ∀ 𝑥 ( 𝑥  ∈  𝐴  →  ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 12 | 10 11 | sylib | ⊢ ( ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸  →  ∀ 𝑥 ( 𝑥  ∈  𝐴  →  ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 13 |  | 19.21v | ⊢ ( ∀ 𝑦 ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) )  ↔  ( 𝑥  ∈  𝐴  →  ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 14 | 13 | albii | ⊢ ( ∀ 𝑥 ∀ 𝑦 ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) )  ↔  ∀ 𝑥 ( 𝑥  ∈  𝐴  →  ∀ 𝑦 ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 15 | 12 14 | sylibr | ⊢ ( ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸  →  ∀ 𝑥 ∀ 𝑦 ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 16 |  | id | ⊢ ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 17 | 16 | alanimi | ⊢ ( ( ∀ 𝑦 ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ∀ 𝑦 ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 18 | 17 | alanimi | ⊢ ( ( ∀ 𝑥 ∀ 𝑦 ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ∀ 𝑥 ∀ 𝑦 ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 19 | 7 15 18 | syl2an | ⊢ ( ( 𝐴  =  𝐵  ∧  ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸 )  →  ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 20 |  | tsan2 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( 𝑥  ∈  𝐴  ∨  ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) | 
						
							| 21 | 20 | ord | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  𝑥  ∈  𝐴  →  ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) | 
						
							| 22 |  | tsbi2 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  ∨  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 23 | 22 | ord | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 24 | 23 | a1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  →  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 25 |  | ax-1 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  →  ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 26 | 24 25 | contrd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 27 | 26 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  𝑥  ∈  𝐴  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 28 | 21 27 | cnf1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  𝑥  ∈  𝐴  →  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 29 |  | simplim | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 30 | 29 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 )  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 31 |  | tsbi3 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 )  ∨  ¬  ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) ) | 
						
							| 32 | 31 | ord | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 )  →  ¬  ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) ) | 
						
							| 33 |  | tsan2 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∨  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 34 | 33 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 )  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∨  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) ) | 
						
							| 35 | 32 34 | cnf1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 )  →  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 36 | 30 35 | contrd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 ) ) | 
						
							| 37 | 36 | ord | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  𝑥  ∈  𝐴  →  ¬  𝑥  ∈  𝐵 ) ) | 
						
							| 38 |  | tsan2 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( 𝑥  ∈  𝐵  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 39 | 38 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  𝑥  ∈  𝐴  →  ( 𝑥  ∈  𝐵  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 40 | 37 39 | cnf1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  𝑥  ∈  𝐴  →  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 41 | 28 40 | contrd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  𝑥  ∈  𝐴 ) | 
						
							| 42 | 41 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  𝑥  ∈  𝐴 ) ) | 
						
							| 43 | 29 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 44 |  | tsan3 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) )  ∨  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 45 | 44 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) )  ∨  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) ) | 
						
							| 46 | 43 45 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 47 | 42 46 | mpdd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 48 |  | notnotr | ⊢ ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) | 
						
							| 49 | 48 | a1i | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 50 | 38 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑥  ∈  𝐵  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 51 | 49 50 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  𝑥  ∈  𝐵 ) ) | 
						
							| 52 | 36 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑥  ∈  𝐴  ∨  ¬  𝑥  ∈  𝐵 ) ) ) | 
						
							| 53 | 51 52 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  𝑥  ∈  𝐴 ) ) | 
						
							| 54 |  | tsan3 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( 𝑦  =  𝐸  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 55 | 54 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑦  =  𝐸  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 56 | 49 55 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  𝑦  =  𝐸 ) ) | 
						
							| 57 | 29 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 58 | 44 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) )  ∨  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) ) | 
						
							| 59 | 57 58 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 60 | 53 59 | mpdd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 61 |  | tsbi3 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( 𝑦  =  𝐷  ∨  ¬  𝑦  =  𝐸 )  ∨  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 62 | 61 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( ( 𝑦  =  𝐷  ∨  ¬  𝑦  =  𝐸 )  ∨  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 63 | 60 62 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑦  =  𝐷  ∨  ¬  𝑦  =  𝐸 ) ) ) | 
						
							| 64 | 56 63 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  𝑦  =  𝐷 ) ) | 
						
							| 65 | 53 64 | jcad | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) | 
						
							| 66 |  | ax-1 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 67 |  | tsim3 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  ∨  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 68 | 67 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( ¬  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  ∨  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) ) ) | 
						
							| 69 | 66 68 | cnf2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ¬  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 70 |  | tsbi1 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  ∨  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 71 | 70 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( ( ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) )  ∨  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) ) | 
						
							| 72 | 69 71 | cnf2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ( ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 73 | 49 72 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 )  →  ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) | 
						
							| 74 | 65 73 | contrd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) | 
						
							| 75 | 74 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ¬  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 76 | 26 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 77 | 75 76 | cnf2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) | 
						
							| 78 |  | tsan3 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( 𝑦  =  𝐷  ∨  ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) | 
						
							| 79 | 78 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( 𝑦  =  𝐷  ∨  ¬  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) ) ) ) | 
						
							| 80 | 77 79 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  𝑦  =  𝐷 ) ) | 
						
							| 81 | 33 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∨  ¬  ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) ) ) | 
						
							| 82 | 43 81 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) ) | 
						
							| 83 |  | tsbi4 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( ¬  𝑥  ∈  𝐴  ∨  𝑥  ∈  𝐵 )  ∨  ¬  ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) ) | 
						
							| 84 | 83 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( ¬  𝑥  ∈  𝐴  ∨  𝑥  ∈  𝐵 )  ∨  ¬  ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 ) ) ) ) | 
						
							| 85 | 82 84 | cnfn2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ¬  𝑥  ∈  𝐴  ∨  𝑥  ∈  𝐵 ) ) ) | 
						
							| 86 | 42 85 | cnfn1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  𝑥  ∈  𝐵 ) ) | 
						
							| 87 |  | tsan1 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( ¬  𝑥  ∈  𝐵  ∨  ¬  𝑦  =  𝐸 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 88 | 87 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( ¬  𝑥  ∈  𝐵  ∨  ¬  𝑦  =  𝐸 )  ∨  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) ) | 
						
							| 89 | 75 88 | cnf2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ¬  𝑥  ∈  𝐵  ∨  ¬  𝑦  =  𝐸 ) ) ) | 
						
							| 90 | 86 89 | cnfn1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ¬  𝑦  =  𝐸 ) ) | 
						
							| 91 |  | tsbi4 | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ( ¬  𝑦  =  𝐷  ∨  𝑦  =  𝐸 )  ∨  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 92 | 91 | a1d | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( ¬  𝑦  =  𝐷  ∨  𝑦  =  𝐸 )  ∨  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 93 | 92 | or32dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ( ¬  𝑦  =  𝐷  ∨  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) )  ∨  𝑦  =  𝐸 ) ) ) | 
						
							| 94 | 90 93 | cnf2dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ( ¬  𝑦  =  𝐷  ∨  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) ) | 
						
							| 95 | 80 94 | cnfn1dd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ( ¬  ⊥  →  ¬  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) ) | 
						
							| 96 | 47 95 | contrd | ⊢ ( ¬  ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) )  →  ⊥ ) | 
						
							| 97 | 96 | efald2 | ⊢ ( ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 98 | 97 | 2alimi | ⊢ ( ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ↔  𝑥  ∈  𝐵 )  ∧  ( 𝑥  ∈  𝐴  →  ( 𝑦  =  𝐷  ↔  𝑦  =  𝐸 ) ) )  →  ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 99 | 19 98 | syl | ⊢ ( ( 𝐴  =  𝐵  ∧  ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸 )  →  ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 100 |  | eqopab2bw | ⊢ ( { 〈 𝑥 ,  𝑦 〉  ∣  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) }  =  { 〈 𝑥 ,  𝑦 〉  ∣  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) }  ↔  ∀ 𝑥 ∀ 𝑦 ( ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) ) ) | 
						
							| 101 | 99 100 | sylibr | ⊢ ( ( 𝐴  =  𝐵  ∧  ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸 )  →  { 〈 𝑥 ,  𝑦 〉  ∣  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) }  =  { 〈 𝑥 ,  𝑦 〉  ∣  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) } ) | 
						
							| 102 |  | df-mpt | ⊢ ( 𝑥  ∈  𝐴  ↦  𝐷 )  =  { 〈 𝑥 ,  𝑦 〉  ∣  ( 𝑥  ∈  𝐴  ∧  𝑦  =  𝐷 ) } | 
						
							| 103 |  | df-mpt | ⊢ ( 𝑥  ∈  𝐵  ↦  𝐸 )  =  { 〈 𝑥 ,  𝑦 〉  ∣  ( 𝑥  ∈  𝐵  ∧  𝑦  =  𝐸 ) } | 
						
							| 104 | 101 102 103 | 3eqtr4g | ⊢ ( ( 𝐴  =  𝐵  ∧  ∀ 𝑥  ∈  𝐴 𝐷  =  𝐸 )  →  ( 𝑥  ∈  𝐴  ↦  𝐷 )  =  ( 𝑥  ∈  𝐵  ↦  𝐸 ) ) |