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Mirrors > Home > MPE Home > Th. List > Mathboxes > setinds | Structured version Visualization version GIF version |
Description: Principle of set induction (or E-induction). If a property passes from all elements of 𝑥 to 𝑥 itself, then it holds for all 𝑥. (Contributed by Scott Fenton, 10-Mar-2011.) |
Ref | Expression |
---|---|
setinds.1 | ⊢ (∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝜑 → 𝜑) |
Ref | Expression |
---|---|
setinds | ⊢ 𝜑 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | vex 3477 | . 2 ⊢ 𝑥 ∈ V | |
2 | setind 9735 | . . . . 5 ⊢ (∀𝑧(𝑧 ⊆ {𝑥 ∣ 𝜑} → 𝑧 ∈ {𝑥 ∣ 𝜑}) → {𝑥 ∣ 𝜑} = V) | |
3 | dfss3 3970 | . . . . . . 7 ⊢ (𝑧 ⊆ {𝑥 ∣ 𝜑} ↔ ∀𝑦 ∈ 𝑧 𝑦 ∈ {𝑥 ∣ 𝜑}) | |
4 | df-sbc 3778 | . . . . . . . . 9 ⊢ ([𝑦 / 𝑥]𝜑 ↔ 𝑦 ∈ {𝑥 ∣ 𝜑}) | |
5 | 4 | ralbii 3092 | . . . . . . . 8 ⊢ (∀𝑦 ∈ 𝑧 [𝑦 / 𝑥]𝜑 ↔ ∀𝑦 ∈ 𝑧 𝑦 ∈ {𝑥 ∣ 𝜑}) |
6 | nfcv 2902 | . . . . . . . . . . 11 ⊢ Ⅎ𝑥𝑧 | |
7 | nfsbc1v 3797 | . . . . . . . . . . 11 ⊢ Ⅎ𝑥[𝑦 / 𝑥]𝜑 | |
8 | 6, 7 | nfralw 3307 | . . . . . . . . . 10 ⊢ Ⅎ𝑥∀𝑦 ∈ 𝑧 [𝑦 / 𝑥]𝜑 |
9 | nfsbc1v 3797 | . . . . . . . . . 10 ⊢ Ⅎ𝑥[𝑧 / 𝑥]𝜑 | |
10 | 8, 9 | nfim 1898 | . . . . . . . . 9 ⊢ Ⅎ𝑥(∀𝑦 ∈ 𝑧 [𝑦 / 𝑥]𝜑 → [𝑧 / 𝑥]𝜑) |
11 | raleq 3321 | . . . . . . . . . 10 ⊢ (𝑥 = 𝑧 → (∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝜑 ↔ ∀𝑦 ∈ 𝑧 [𝑦 / 𝑥]𝜑)) | |
12 | sbceq1a 3788 | . . . . . . . . . 10 ⊢ (𝑥 = 𝑧 → (𝜑 ↔ [𝑧 / 𝑥]𝜑)) | |
13 | 11, 12 | imbi12d 344 | . . . . . . . . 9 ⊢ (𝑥 = 𝑧 → ((∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝜑 → 𝜑) ↔ (∀𝑦 ∈ 𝑧 [𝑦 / 𝑥]𝜑 → [𝑧 / 𝑥]𝜑))) |
14 | setinds.1 | . . . . . . . . 9 ⊢ (∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝜑 → 𝜑) | |
15 | 10, 13, 14 | chvarfv 2232 | . . . . . . . 8 ⊢ (∀𝑦 ∈ 𝑧 [𝑦 / 𝑥]𝜑 → [𝑧 / 𝑥]𝜑) |
16 | 5, 15 | sylbir 234 | . . . . . . 7 ⊢ (∀𝑦 ∈ 𝑧 𝑦 ∈ {𝑥 ∣ 𝜑} → [𝑧 / 𝑥]𝜑) |
17 | 3, 16 | sylbi 216 | . . . . . 6 ⊢ (𝑧 ⊆ {𝑥 ∣ 𝜑} → [𝑧 / 𝑥]𝜑) |
18 | df-sbc 3778 | . . . . . 6 ⊢ ([𝑧 / 𝑥]𝜑 ↔ 𝑧 ∈ {𝑥 ∣ 𝜑}) | |
19 | 17, 18 | sylib 217 | . . . . 5 ⊢ (𝑧 ⊆ {𝑥 ∣ 𝜑} → 𝑧 ∈ {𝑥 ∣ 𝜑}) |
20 | 2, 19 | mpg 1798 | . . . 4 ⊢ {𝑥 ∣ 𝜑} = V |
21 | 20 | eqcomi 2740 | . . 3 ⊢ V = {𝑥 ∣ 𝜑} |
22 | 21 | eqabri 2876 | . 2 ⊢ (𝑥 ∈ V ↔ 𝜑) |
23 | 1, 22 | mpbi 229 | 1 ⊢ 𝜑 |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 = wceq 1540 ∈ wcel 2105 {cab 2708 ∀wral 3060 Vcvv 3473 [wsbc 3777 ⊆ wss 3948 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1796 ax-4 1810 ax-5 1912 ax-6 1970 ax-7 2010 ax-8 2107 ax-9 2115 ax-10 2136 ax-11 2153 ax-12 2170 ax-ext 2702 ax-rep 5285 ax-sep 5299 ax-nul 5306 ax-pr 5427 ax-un 7729 ax-reg 9593 ax-inf2 9642 |
This theorem depends on definitions: df-bi 206 df-an 396 df-or 845 df-3or 1087 df-3an 1088 df-tru 1543 df-fal 1553 df-ex 1781 df-nf 1785 df-sb 2067 df-mo 2533 df-eu 2562 df-clab 2709 df-cleq 2723 df-clel 2809 df-nfc 2884 df-ne 2940 df-ral 3061 df-rex 3070 df-reu 3376 df-rab 3432 df-v 3475 df-sbc 3778 df-csb 3894 df-dif 3951 df-un 3953 df-in 3955 df-ss 3965 df-pss 3967 df-nul 4323 df-if 4529 df-pw 4604 df-sn 4629 df-pr 4631 df-op 4635 df-uni 4909 df-iun 4999 df-br 5149 df-opab 5211 df-mpt 5232 df-tr 5266 df-id 5574 df-eprel 5580 df-po 5588 df-so 5589 df-fr 5631 df-we 5633 df-xp 5682 df-rel 5683 df-cnv 5684 df-co 5685 df-dm 5686 df-rn 5687 df-res 5688 df-ima 5689 df-pred 6300 df-ord 6367 df-on 6368 df-lim 6369 df-suc 6370 df-iota 6495 df-fun 6545 df-fn 6546 df-f 6547 df-f1 6548 df-fo 6549 df-f1o 6550 df-fv 6551 df-ov 7415 df-om 7860 df-2nd 7980 df-frecs 8272 df-wrecs 8303 df-recs 8377 df-rdg 8416 |
This theorem is referenced by: setinds2f 35222 |
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