Metamath Proof Explorer


Theorem evthf

Description: A version of evth using bound-variable hypotheses instead of distinct variable conditions. (Contributed by Glauco Siliprandi, 20-Apr-2017)

Ref Expression
Hypotheses evthf.1 𝑥 𝐹
evthf.2 𝑦 𝐹
evthf.3 𝑥 𝑋
evthf.4 𝑦 𝑋
evthf.5 𝑥 𝜑
evthf.6 𝑦 𝜑
evthf.7 𝑋 = 𝐽
evthf.8 𝐾 = ( topGen ‘ ran (,) )
evthf.9 ( 𝜑𝐽 ∈ Comp )
evthf.10 ( 𝜑𝐹 ∈ ( 𝐽 Cn 𝐾 ) )
evthf.11 ( 𝜑𝑋 ≠ ∅ )
Assertion evthf ( 𝜑 → ∃ 𝑥𝑋𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 ) )

Proof

Step Hyp Ref Expression
1 evthf.1 𝑥 𝐹
2 evthf.2 𝑦 𝐹
3 evthf.3 𝑥 𝑋
4 evthf.4 𝑦 𝑋
5 evthf.5 𝑥 𝜑
6 evthf.6 𝑦 𝜑
7 evthf.7 𝑋 = 𝐽
8 evthf.8 𝐾 = ( topGen ‘ ran (,) )
9 evthf.9 ( 𝜑𝐽 ∈ Comp )
10 evthf.10 ( 𝜑𝐹 ∈ ( 𝐽 Cn 𝐾 ) )
11 evthf.11 ( 𝜑𝑋 ≠ ∅ )
12 7 8 9 10 11 evth ( 𝜑 → ∃ 𝑎𝑋𝑏𝑋 ( 𝐹𝑏 ) ≤ ( 𝐹𝑎 ) )
13 nfcv 𝑏 𝑋
14 nfcv 𝑦 𝑏
15 2 14 nffv 𝑦 ( 𝐹𝑏 )
16 nfcv 𝑦
17 nfcv 𝑦 𝑎
18 2 17 nffv 𝑦 ( 𝐹𝑎 )
19 15 16 18 nfbr 𝑦 ( 𝐹𝑏 ) ≤ ( 𝐹𝑎 )
20 nfv 𝑏 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 )
21 fveq2 ( 𝑏 = 𝑦 → ( 𝐹𝑏 ) = ( 𝐹𝑦 ) )
22 21 breq1d ( 𝑏 = 𝑦 → ( ( 𝐹𝑏 ) ≤ ( 𝐹𝑎 ) ↔ ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 ) ) )
23 13 4 19 20 22 cbvralfw ( ∀ 𝑏𝑋 ( 𝐹𝑏 ) ≤ ( 𝐹𝑎 ) ↔ ∀ 𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 ) )
24 23 rexbii ( ∃ 𝑎𝑋𝑏𝑋 ( 𝐹𝑏 ) ≤ ( 𝐹𝑎 ) ↔ ∃ 𝑎𝑋𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 ) )
25 nfcv 𝑎 𝑋
26 nfcv 𝑥 𝑦
27 1 26 nffv 𝑥 ( 𝐹𝑦 )
28 nfcv 𝑥
29 nfcv 𝑥 𝑎
30 1 29 nffv 𝑥 ( 𝐹𝑎 )
31 27 28 30 nfbr 𝑥 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 )
32 3 31 nfralw 𝑥𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 )
33 nfv 𝑎𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 )
34 fveq2 ( 𝑎 = 𝑥 → ( 𝐹𝑎 ) = ( 𝐹𝑥 ) )
35 34 breq2d ( 𝑎 = 𝑥 → ( ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 ) ↔ ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 ) ) )
36 35 ralbidv ( 𝑎 = 𝑥 → ( ∀ 𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 ) ↔ ∀ 𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 ) ) )
37 25 3 32 33 36 cbvrexfw ( ∃ 𝑎𝑋𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑎 ) ↔ ∃ 𝑥𝑋𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 ) )
38 24 37 bitri ( ∃ 𝑎𝑋𝑏𝑋 ( 𝐹𝑏 ) ≤ ( 𝐹𝑎 ) ↔ ∃ 𝑥𝑋𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 ) )
39 12 38 sylib ( 𝜑 → ∃ 𝑥𝑋𝑦𝑋 ( 𝐹𝑦 ) ≤ ( 𝐹𝑥 ) )