| Step | Hyp | Ref | Expression | 
						
							| 1 |  | finminlem.1 | ⊢ ( 𝑥  =  𝑦  →  ( 𝜑  ↔  𝜓 ) ) | 
						
							| 2 |  | nfe1 | ⊢ Ⅎ 𝑥 ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) | 
						
							| 3 |  | nfcv | ⊢ Ⅎ 𝑥 ω | 
						
							| 4 | 2 3 | nfrabw | ⊢ Ⅎ 𝑥 { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) } | 
						
							| 5 |  | nfcv | ⊢ Ⅎ 𝑥 ∅ | 
						
							| 6 | 4 5 | nfne | ⊢ Ⅎ 𝑥 { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ | 
						
							| 7 |  | isfi | ⊢ ( 𝑥  ∈  Fin  ↔  ∃ 𝑚  ∈  ω 𝑥  ≈  𝑚 ) | 
						
							| 8 |  | 19.8a | ⊢ ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  →  ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 ) ) | 
						
							| 9 | 8 | anim2i | ⊢ ( ( 𝑚  ∈  ω  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( 𝑚  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 ) ) ) | 
						
							| 10 | 9 | 3impb | ⊢ ( ( 𝑚  ∈  ω  ∧  𝑥  ≈  𝑚  ∧  𝜑 )  →  ( 𝑚  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 ) ) ) | 
						
							| 11 |  | breq2 | ⊢ ( 𝑛  =  𝑚  →  ( 𝑥  ≈  𝑛  ↔  𝑥  ≈  𝑚 ) ) | 
						
							| 12 | 11 | anbi1d | ⊢ ( 𝑛  =  𝑚  →  ( ( 𝑥  ≈  𝑛  ∧  𝜑 )  ↔  ( 𝑥  ≈  𝑚  ∧  𝜑 ) ) ) | 
						
							| 13 | 12 | exbidv | ⊢ ( 𝑛  =  𝑚  →  ( ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 )  ↔  ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 ) ) ) | 
						
							| 14 | 13 | elrab | ⊢ ( 𝑚  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ↔  ( 𝑚  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 ) ) ) | 
						
							| 15 | 10 14 | sylibr | ⊢ ( ( 𝑚  ∈  ω  ∧  𝑥  ≈  𝑚  ∧  𝜑 )  →  𝑚  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) } ) | 
						
							| 16 | 15 | ne0d | ⊢ ( ( 𝑚  ∈  ω  ∧  𝑥  ≈  𝑚  ∧  𝜑 )  →  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ ) | 
						
							| 17 | 16 | 3exp | ⊢ ( 𝑚  ∈  ω  →  ( 𝑥  ≈  𝑚  →  ( 𝜑  →  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ ) ) ) | 
						
							| 18 | 17 | rexlimiv | ⊢ ( ∃ 𝑚  ∈  ω 𝑥  ≈  𝑚  →  ( 𝜑  →  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ ) ) | 
						
							| 19 | 7 18 | sylbi | ⊢ ( 𝑥  ∈  Fin  →  ( 𝜑  →  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ ) ) | 
						
							| 20 | 6 19 | rexlimi | ⊢ ( ∃ 𝑥  ∈  Fin 𝜑  →  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ ) | 
						
							| 21 |  | epweon | ⊢  E   We  On | 
						
							| 22 |  | ssrab2 | ⊢ { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ⊆  ω | 
						
							| 23 |  | omsson | ⊢ ω  ⊆  On | 
						
							| 24 | 22 23 | sstri | ⊢ { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ⊆  On | 
						
							| 25 |  | wefrc | ⊢ ( (  E   We  On  ∧  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ⊆  On  ∧  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅ )  →  ∃ 𝑚  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) } ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ ) | 
						
							| 26 | 21 24 25 | mp3an12 | ⊢ ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ≠  ∅  →  ∃ 𝑚  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) } ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ ) | 
						
							| 27 |  | nfv | ⊢ Ⅎ 𝑥 𝑚  ∈  ω | 
						
							| 28 |  | nfcv | ⊢ Ⅎ 𝑥 𝑚 | 
						
							| 29 | 4 28 | nfin | ⊢ Ⅎ 𝑥 ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 ) | 
						
							| 30 | 29 | nfeq1 | ⊢ Ⅎ 𝑥 ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ | 
						
							| 31 | 27 30 | nfan | ⊢ Ⅎ 𝑥 ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ ) | 
						
							| 32 |  | simprr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  𝜑 ) | 
						
							| 33 |  | sspss | ⊢ ( 𝑦  ⊆  𝑥  ↔  ( 𝑦  ⊊  𝑥  ∨  𝑦  =  𝑥 ) ) | 
						
							| 34 |  | rspe | ⊢ ( ( 𝑚  ∈  ω  ∧  𝑥  ≈  𝑚 )  →  ∃ 𝑚  ∈  ω 𝑥  ≈  𝑚 ) | 
						
							| 35 |  | pssss | ⊢ ( 𝑦  ⊊  𝑥  →  𝑦  ⊆  𝑥 ) | 
						
							| 36 |  | ssfi | ⊢ ( ( 𝑥  ∈  Fin  ∧  𝑦  ⊆  𝑥 )  →  𝑦  ∈  Fin ) | 
						
							| 37 | 35 36 | sylan2 | ⊢ ( ( 𝑥  ∈  Fin  ∧  𝑦  ⊊  𝑥 )  →  𝑦  ∈  Fin ) | 
						
							| 38 | 37 | ex | ⊢ ( 𝑥  ∈  Fin  →  ( 𝑦  ⊊  𝑥  →  𝑦  ∈  Fin ) ) | 
						
							| 39 | 7 38 | sylbir | ⊢ ( ∃ 𝑚  ∈  ω 𝑥  ≈  𝑚  →  ( 𝑦  ⊊  𝑥  →  𝑦  ∈  Fin ) ) | 
						
							| 40 | 34 39 | syl | ⊢ ( ( 𝑚  ∈  ω  ∧  𝑥  ≈  𝑚 )  →  ( 𝑦  ⊊  𝑥  →  𝑦  ∈  Fin ) ) | 
						
							| 41 | 40 | adantrr | ⊢ ( ( 𝑚  ∈  ω  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( 𝑦  ⊊  𝑥  →  𝑦  ∈  Fin ) ) | 
						
							| 42 | 41 | adantrr | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  ⊊  𝑥  →  𝑦  ∈  Fin ) ) | 
						
							| 43 |  | isfi | ⊢ ( 𝑦  ∈  Fin  ↔  ∃ 𝑘  ∈  ω 𝑦  ≈  𝑘 ) | 
						
							| 44 |  | simprll | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  𝑘  ∈  ω ) | 
						
							| 45 |  | simprlr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  𝑦  ≈  𝑘 ) | 
						
							| 46 |  | simplrr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  𝜓 ) | 
						
							| 47 |  | vex | ⊢ 𝑦  ∈  V | 
						
							| 48 |  | breq1 | ⊢ ( 𝑥  =  𝑦  →  ( 𝑥  ≈  𝑘  ↔  𝑦  ≈  𝑘 ) ) | 
						
							| 49 | 48 1 | anbi12d | ⊢ ( 𝑥  =  𝑦  →  ( ( 𝑥  ≈  𝑘  ∧  𝜑 )  ↔  ( 𝑦  ≈  𝑘  ∧  𝜓 ) ) ) | 
						
							| 50 | 47 49 | spcev | ⊢ ( ( 𝑦  ≈  𝑘  ∧  𝜓 )  →  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) ) | 
						
							| 51 | 45 46 50 | syl2anc | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) ) | 
						
							| 52 | 34 7 | sylibr | ⊢ ( ( 𝑚  ∈  ω  ∧  𝑥  ≈  𝑚 )  →  𝑥  ∈  Fin ) | 
						
							| 53 | 52 | adantrr | ⊢ ( ( 𝑚  ∈  ω  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  𝑥  ∈  Fin ) | 
						
							| 54 | 53 | adantrr | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  𝑥  ∈  Fin ) | 
						
							| 55 | 54 | adantr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  𝑥  ∈  Fin ) | 
						
							| 56 |  | php3 | ⊢ ( ( 𝑥  ∈  Fin  ∧  𝑦  ⊊  𝑥 )  →  𝑦  ≺  𝑥 ) | 
						
							| 57 | 56 | ex | ⊢ ( 𝑥  ∈  Fin  →  ( 𝑦  ⊊  𝑥  →  𝑦  ≺  𝑥 ) ) | 
						
							| 58 | 55 57 | syl | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑦  ⊊  𝑥  →  𝑦  ≺  𝑥 ) ) | 
						
							| 59 |  | vex | ⊢ 𝑘  ∈  V | 
						
							| 60 |  | ssdomg | ⊢ ( 𝑘  ∈  V  →  ( 𝑚  ⊆  𝑘  →  𝑚  ≼  𝑘 ) ) | 
						
							| 61 | 59 60 | ax-mp | ⊢ ( 𝑚  ⊆  𝑘  →  𝑚  ≼  𝑘 ) | 
						
							| 62 |  | endomtr | ⊢ ( ( 𝑥  ≈  𝑚  ∧  𝑚  ≼  𝑘 )  →  𝑥  ≼  𝑘 ) | 
						
							| 63 | 62 | ex | ⊢ ( 𝑥  ≈  𝑚  →  ( 𝑚  ≼  𝑘  →  𝑥  ≼  𝑘 ) ) | 
						
							| 64 | 63 | ad2antrr | ⊢ ( ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 )  →  ( 𝑚  ≼  𝑘  →  𝑥  ≼  𝑘 ) ) | 
						
							| 65 | 64 | ad2antlr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑚  ≼  𝑘  →  𝑥  ≼  𝑘 ) ) | 
						
							| 66 |  | ensym | ⊢ ( 𝑦  ≈  𝑘  →  𝑘  ≈  𝑦 ) | 
						
							| 67 |  | domentr | ⊢ ( ( 𝑥  ≼  𝑘  ∧  𝑘  ≈  𝑦 )  →  𝑥  ≼  𝑦 ) | 
						
							| 68 | 66 67 | sylan2 | ⊢ ( ( 𝑥  ≼  𝑘  ∧  𝑦  ≈  𝑘 )  →  𝑥  ≼  𝑦 ) | 
						
							| 69 | 68 | expcom | ⊢ ( 𝑦  ≈  𝑘  →  ( 𝑥  ≼  𝑘  →  𝑥  ≼  𝑦 ) ) | 
						
							| 70 | 69 | ad2antll | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑥  ≼  𝑘  →  𝑥  ≼  𝑦 ) ) | 
						
							| 71 | 65 70 | syld | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑚  ≼  𝑘  →  𝑥  ≼  𝑦 ) ) | 
						
							| 72 | 61 71 | syl5 | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑚  ⊆  𝑘  →  𝑥  ≼  𝑦 ) ) | 
						
							| 73 |  | domnsym | ⊢ ( 𝑥  ≼  𝑦  →  ¬  𝑦  ≺  𝑥 ) | 
						
							| 74 | 73 | con2i | ⊢ ( 𝑦  ≺  𝑥  →  ¬  𝑥  ≼  𝑦 ) | 
						
							| 75 | 72 74 | nsyli | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑦  ≺  𝑥  →  ¬  𝑚  ⊆  𝑘 ) ) | 
						
							| 76 | 58 75 | syld | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 ) )  →  ( 𝑦  ⊊  𝑥  →  ¬  𝑚  ⊆  𝑘 ) ) | 
						
							| 77 | 76 | impr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  ¬  𝑚  ⊆  𝑘 ) | 
						
							| 78 |  | nnord | ⊢ ( 𝑚  ∈  ω  →  Ord  𝑚 ) | 
						
							| 79 | 78 | ad2antrr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  Ord  𝑚 ) | 
						
							| 80 |  | nnord | ⊢ ( 𝑘  ∈  ω  →  Ord  𝑘 ) | 
						
							| 81 | 80 | adantr | ⊢ ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  →  Ord  𝑘 ) | 
						
							| 82 | 81 | ad2antrl | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  Ord  𝑘 ) | 
						
							| 83 |  | ordtri1 | ⊢ ( ( Ord  𝑚  ∧  Ord  𝑘 )  →  ( 𝑚  ⊆  𝑘  ↔  ¬  𝑘  ∈  𝑚 ) ) | 
						
							| 84 | 83 | con2bid | ⊢ ( ( Ord  𝑚  ∧  Ord  𝑘 )  →  ( 𝑘  ∈  𝑚  ↔  ¬  𝑚  ⊆  𝑘 ) ) | 
						
							| 85 | 79 82 84 | syl2anc | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  ( 𝑘  ∈  𝑚  ↔  ¬  𝑚  ⊆  𝑘 ) ) | 
						
							| 86 | 77 85 | mpbird | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  𝑘  ∈  𝑚 ) | 
						
							| 87 | 44 51 86 | jca31 | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  ( ( 𝑘  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) )  ∧  𝑘  ∈  𝑚 ) ) | 
						
							| 88 |  | elin | ⊢ ( 𝑘  ∈  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ↔  ( 𝑘  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∧  𝑘  ∈  𝑚 ) ) | 
						
							| 89 |  | breq2 | ⊢ ( 𝑛  =  𝑘  →  ( 𝑥  ≈  𝑛  ↔  𝑥  ≈  𝑘 ) ) | 
						
							| 90 | 89 | anbi1d | ⊢ ( 𝑛  =  𝑘  →  ( ( 𝑥  ≈  𝑛  ∧  𝜑 )  ↔  ( 𝑥  ≈  𝑘  ∧  𝜑 ) ) ) | 
						
							| 91 | 90 | exbidv | ⊢ ( 𝑛  =  𝑘  →  ( ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 )  ↔  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) ) ) | 
						
							| 92 | 91 | elrab | ⊢ ( 𝑘  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ↔  ( 𝑘  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) ) ) | 
						
							| 93 | 92 | anbi1i | ⊢ ( ( 𝑘  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∧  𝑘  ∈  𝑚 )  ↔  ( ( 𝑘  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) )  ∧  𝑘  ∈  𝑚 ) ) | 
						
							| 94 | 88 93 | bitri | ⊢ ( 𝑘  ∈  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ↔  ( ( 𝑘  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑘  ∧  𝜑 ) )  ∧  𝑘  ∈  𝑚 ) ) | 
						
							| 95 | 87 94 | sylibr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  𝑘  ∈  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 ) ) | 
						
							| 96 | 95 | ne0d | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  ∧  ( ( 𝑘  ∈  ω  ∧  𝑦  ≈  𝑘 )  ∧  𝑦  ⊊  𝑥 ) )  →  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ≠  ∅ ) | 
						
							| 97 | 96 | exp44 | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑘  ∈  ω  →  ( 𝑦  ≈  𝑘  →  ( 𝑦  ⊊  𝑥  →  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ≠  ∅ ) ) ) ) | 
						
							| 98 | 97 | rexlimdv | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( ∃ 𝑘  ∈  ω 𝑦  ≈  𝑘  →  ( 𝑦  ⊊  𝑥  →  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ≠  ∅ ) ) ) | 
						
							| 99 | 43 98 | biimtrid | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  ∈  Fin  →  ( 𝑦  ⊊  𝑥  →  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ≠  ∅ ) ) ) | 
						
							| 100 | 99 | com23 | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  ⊊  𝑥  →  ( 𝑦  ∈  Fin  →  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ≠  ∅ ) ) ) | 
						
							| 101 | 42 100 | mpdd | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  ⊊  𝑥  →  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  ≠  ∅ ) ) | 
						
							| 102 | 101 | necon2bd | ⊢ ( ( 𝑚  ∈  ω  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅  →  ¬  𝑦  ⊊  𝑥 ) ) | 
						
							| 103 | 102 | ex | ⊢ ( 𝑚  ∈  ω  →  ( ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 )  →  ( ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅  →  ¬  𝑦  ⊊  𝑥 ) ) ) | 
						
							| 104 | 103 | com23 | ⊢ ( 𝑚  ∈  ω  →  ( ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅  →  ( ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 )  →  ¬  𝑦  ⊊  𝑥 ) ) ) | 
						
							| 105 | 104 | imp31 | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ¬  𝑦  ⊊  𝑥 ) | 
						
							| 106 | 105 | pm2.21d | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  ⊊  𝑥  →  𝑥  =  𝑦 ) ) | 
						
							| 107 |  | equcomi | ⊢ ( 𝑦  =  𝑥  →  𝑥  =  𝑦 ) | 
						
							| 108 | 107 | a1i | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  =  𝑥  →  𝑥  =  𝑦 ) ) | 
						
							| 109 | 106 108 | jaod | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( ( 𝑦  ⊊  𝑥  ∨  𝑦  =  𝑥 )  →  𝑥  =  𝑦 ) ) | 
						
							| 110 | 33 109 | biimtrid | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  ∧  𝜓 ) )  →  ( 𝑦  ⊆  𝑥  →  𝑥  =  𝑦 ) ) | 
						
							| 111 | 110 | expr | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( 𝜓  →  ( 𝑦  ⊆  𝑥  →  𝑥  =  𝑦 ) ) ) | 
						
							| 112 | 111 | com23 | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( 𝑦  ⊆  𝑥  →  ( 𝜓  →  𝑥  =  𝑦 ) ) ) | 
						
							| 113 | 112 | impd | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) | 
						
							| 114 | 113 | alrimiv | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) | 
						
							| 115 | 32 114 | jca | ⊢ ( ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  ∧  ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) | 
						
							| 116 | 115 | ex | ⊢ ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  →  ( ( 𝑥  ≈  𝑚  ∧  𝜑 )  →  ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 117 | 31 116 | eximd | ⊢ ( ( 𝑚  ∈  ω  ∧  ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅ )  →  ( ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 )  →  ∃ 𝑥 ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 118 | 117 | impancom | ⊢ ( ( 𝑚  ∈  ω  ∧  ∃ 𝑥 ( 𝑥  ≈  𝑚  ∧  𝜑 ) )  →  ( ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅  →  ∃ 𝑥 ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 119 | 14 118 | sylbi | ⊢ ( 𝑚  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  →  ( ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅  →  ∃ 𝑥 ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) ) | 
						
							| 120 | 119 | rexlimiv | ⊢ ( ∃ 𝑚  ∈  { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) } ( { 𝑛  ∈  ω  ∣  ∃ 𝑥 ( 𝑥  ≈  𝑛  ∧  𝜑 ) }  ∩  𝑚 )  =  ∅  →  ∃ 𝑥 ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) | 
						
							| 121 | 20 26 120 | 3syl | ⊢ ( ∃ 𝑥  ∈  Fin 𝜑  →  ∃ 𝑥 ( 𝜑  ∧  ∀ 𝑦 ( ( 𝑦  ⊆  𝑥  ∧  𝜓 )  →  𝑥  =  𝑦 ) ) ) |