Metamath Proof Explorer


Theorem pconnconn

Description: A path-connected space is connected. (Contributed by Mario Carneiro, 11-Feb-2015)

Ref Expression
Assertion pconnconn ( 𝐽 ∈ PConn → 𝐽 ∈ Conn )

Proof

Step Hyp Ref Expression
1 df-3an ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ∧ ( 𝑥𝑦 ) = ∅ ) ↔ ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ) ∧ ( 𝑥𝑦 ) = ∅ ) )
2 n0 ( 𝑥 ≠ ∅ ↔ ∃ 𝑎 𝑎𝑥 )
3 n0 ( 𝑦 ≠ ∅ ↔ ∃ 𝑏 𝑏𝑦 )
4 2 3 anbi12i ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ) ↔ ( ∃ 𝑎 𝑎𝑥 ∧ ∃ 𝑏 𝑏𝑦 ) )
5 exdistrv ( ∃ 𝑎𝑏 ( 𝑎𝑥𝑏𝑦 ) ↔ ( ∃ 𝑎 𝑎𝑥 ∧ ∃ 𝑏 𝑏𝑦 ) )
6 4 5 bitr4i ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ) ↔ ∃ 𝑎𝑏 ( 𝑎𝑥𝑏𝑦 ) )
7 simpll ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝐽 ∈ PConn )
8 simprll ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝑎𝑥 )
9 simplrl ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝑥𝐽 )
10 elunii ( ( 𝑎𝑥𝑥𝐽 ) → 𝑎 𝐽 )
11 8 9 10 syl2anc ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝑎 𝐽 )
12 simprlr ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝑏𝑦 )
13 simplrr ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝑦𝐽 )
14 elunii ( ( 𝑏𝑦𝑦𝐽 ) → 𝑏 𝐽 )
15 12 13 14 syl2anc ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → 𝑏 𝐽 )
16 eqid 𝐽 = 𝐽
17 16 pconncn ( ( 𝐽 ∈ PConn ∧ 𝑎 𝐽𝑏 𝐽 ) → ∃ 𝑓 ∈ ( II Cn 𝐽 ) ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) )
18 7 11 15 17 syl3anc ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → ∃ 𝑓 ∈ ( II Cn 𝐽 ) ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) )
19 simplrr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑥𝑦 ) = ∅ )
20 simplrr ( ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) → ( 𝑓 ‘ 1 ) = 𝑏 )
21 20 adantl ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑓 ‘ 1 ) = 𝑏 )
22 iiuni ( 0 [,] 1 ) = II
23 iiconn II ∈ Conn
24 23 a1i ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → II ∈ Conn )
25 simprll ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑓 ∈ ( II Cn 𝐽 ) )
26 9 adantr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑥𝐽 )
27 uncom ( 𝑦𝑥 ) = ( 𝑥𝑦 )
28 simprr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑥𝑦 ) = 𝐽 )
29 27 28 syl5eq ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑦𝑥 ) = 𝐽 )
30 13 adantr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑦𝐽 )
31 elssuni ( 𝑦𝐽𝑦 𝐽 )
32 30 31 syl ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑦 𝐽 )
33 incom ( 𝑦𝑥 ) = ( 𝑥𝑦 )
34 33 19 syl5eq ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑦𝑥 ) = ∅ )
35 uneqdifeq ( ( 𝑦 𝐽 ∧ ( 𝑦𝑥 ) = ∅ ) → ( ( 𝑦𝑥 ) = 𝐽 ↔ ( 𝐽𝑦 ) = 𝑥 ) )
36 32 34 35 syl2anc ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( ( 𝑦𝑥 ) = 𝐽 ↔ ( 𝐽𝑦 ) = 𝑥 ) )
37 29 36 mpbid ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝐽𝑦 ) = 𝑥 )
38 pconntop ( 𝐽 ∈ PConn → 𝐽 ∈ Top )
39 38 ad3antrrr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝐽 ∈ Top )
40 16 opncld ( ( 𝐽 ∈ Top ∧ 𝑦𝐽 ) → ( 𝐽𝑦 ) ∈ ( Clsd ‘ 𝐽 ) )
41 39 30 40 syl2anc ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝐽𝑦 ) ∈ ( Clsd ‘ 𝐽 ) )
42 37 41 eqeltrrd ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑥 ∈ ( Clsd ‘ 𝐽 ) )
43 0elunit 0 ∈ ( 0 [,] 1 )
44 43 a1i ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 0 ∈ ( 0 [,] 1 ) )
45 simplrl ( ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) → ( 𝑓 ‘ 0 ) = 𝑎 )
46 45 adantl ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑓 ‘ 0 ) = 𝑎 )
47 8 adantr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑎𝑥 )
48 46 47 eqeltrd ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑓 ‘ 0 ) ∈ 𝑥 )
49 22 24 25 26 42 44 48 conncn ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑓 : ( 0 [,] 1 ) ⟶ 𝑥 )
50 1elunit 1 ∈ ( 0 [,] 1 )
51 ffvelrn ( ( 𝑓 : ( 0 [,] 1 ) ⟶ 𝑥 ∧ 1 ∈ ( 0 [,] 1 ) ) → ( 𝑓 ‘ 1 ) ∈ 𝑥 )
52 49 50 51 sylancl ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑓 ‘ 1 ) ∈ 𝑥 )
53 21 52 eqeltrrd ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑏𝑥 )
54 12 adantr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → 𝑏𝑦 )
55 inelcm ( ( 𝑏𝑥𝑏𝑦 ) → ( 𝑥𝑦 ) ≠ ∅ )
56 53 54 55 syl2anc ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ( 𝑥𝑦 ) ≠ ∅ )
57 19 56 pm2.21ddne ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ∧ ( 𝑥𝑦 ) = 𝐽 ) ) → ¬ ( 𝑥𝑦 ) = 𝐽 )
58 57 expr ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ) → ( ( 𝑥𝑦 ) = 𝐽 → ¬ ( 𝑥𝑦 ) = 𝐽 ) )
59 58 pm2.01d ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ) → ¬ ( 𝑥𝑦 ) = 𝐽 )
60 59 neqned ( ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) ∧ ( 𝑓 ∈ ( II Cn 𝐽 ) ∧ ( ( 𝑓 ‘ 0 ) = 𝑎 ∧ ( 𝑓 ‘ 1 ) = 𝑏 ) ) ) → ( 𝑥𝑦 ) ≠ 𝐽 )
61 18 60 rexlimddv ( ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) ∧ ( ( 𝑎𝑥𝑏𝑦 ) ∧ ( 𝑥𝑦 ) = ∅ ) ) → ( 𝑥𝑦 ) ≠ 𝐽 )
62 61 exp32 ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) → ( ( 𝑎𝑥𝑏𝑦 ) → ( ( 𝑥𝑦 ) = ∅ → ( 𝑥𝑦 ) ≠ 𝐽 ) ) )
63 62 exlimdvv ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) → ( ∃ 𝑎𝑏 ( 𝑎𝑥𝑏𝑦 ) → ( ( 𝑥𝑦 ) = ∅ → ( 𝑥𝑦 ) ≠ 𝐽 ) ) )
64 6 63 syl5bi ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) → ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ) → ( ( 𝑥𝑦 ) = ∅ → ( 𝑥𝑦 ) ≠ 𝐽 ) ) )
65 64 impd ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) → ( ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ) ∧ ( 𝑥𝑦 ) = ∅ ) → ( 𝑥𝑦 ) ≠ 𝐽 ) )
66 1 65 syl5bi ( ( 𝐽 ∈ PConn ∧ ( 𝑥𝐽𝑦𝐽 ) ) → ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ∧ ( 𝑥𝑦 ) = ∅ ) → ( 𝑥𝑦 ) ≠ 𝐽 ) )
67 66 ralrimivva ( 𝐽 ∈ PConn → ∀ 𝑥𝐽𝑦𝐽 ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ∧ ( 𝑥𝑦 ) = ∅ ) → ( 𝑥𝑦 ) ≠ 𝐽 ) )
68 16 toptopon ( 𝐽 ∈ Top ↔ 𝐽 ∈ ( TopOn ‘ 𝐽 ) )
69 38 68 sylib ( 𝐽 ∈ PConn → 𝐽 ∈ ( TopOn ‘ 𝐽 ) )
70 dfconn2 ( 𝐽 ∈ ( TopOn ‘ 𝐽 ) → ( 𝐽 ∈ Conn ↔ ∀ 𝑥𝐽𝑦𝐽 ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ∧ ( 𝑥𝑦 ) = ∅ ) → ( 𝑥𝑦 ) ≠ 𝐽 ) ) )
71 69 70 syl ( 𝐽 ∈ PConn → ( 𝐽 ∈ Conn ↔ ∀ 𝑥𝐽𝑦𝐽 ( ( 𝑥 ≠ ∅ ∧ 𝑦 ≠ ∅ ∧ ( 𝑥𝑦 ) = ∅ ) → ( 𝑥𝑦 ) ≠ 𝐽 ) ) )
72 67 71 mpbird ( 𝐽 ∈ PConn → 𝐽 ∈ Conn )