Theorem ordtri2or2exmid 4555

Description: Ordinal trichotomy implies excluded middle. (Contributed by Jim Kingdon, 29-Aug-2021.)

Hypothesis

Ref	Expression
ordtri2or2exmid.1	⊢ ∀𝑥 ∈ On ∀𝑦 ∈ On (𝑥 ⊆ 𝑦 ∨ 𝑦 ⊆ 𝑥)

Assertion

Ref	Expression
ordtri2or2exmid	⊢ (𝜑 ∨ ¬ 𝜑)

Distinct variable group:   𝜑,𝑥,𝑦

Proof of Theorem ordtri2or2exmid

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		ordtri2or2exmid.1	. . . 4 ⊢ ∀𝑥 ∈ On ∀𝑦 ∈ On (𝑥 ⊆ 𝑦 ∨ 𝑦 ⊆ 𝑥)
2		ordtri2or2exmidlem 4510	. . . . 5 ⊢ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ∈ On
3		suc0 4396	. . . . . 6 ⊢ suc ∅ = {∅}
4		0elon 4377	. . . . . . 7 ⊢ ∅ ∈ On
5	4	onsuci 4500	. . . . . 6 ⊢ suc ∅ ∈ On
6	3, 5	eqeltrri 2244	. . . . 5 ⊢ {∅} ∈ On
7		sseq1 3170	. . . . . . 7 ⊢ (𝑥 = {𝑧 ∈ {∅, {∅}} ∣ 𝜑} → (𝑥 ⊆ 𝑦 ↔ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ 𝑦))
8		sseq2 3171	. . . . . . 7 ⊢ (𝑥 = {𝑧 ∈ {∅, {∅}} ∣ 𝜑} → (𝑦 ⊆ 𝑥 ↔ 𝑦 ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}))
9	7, 8	orbi12d 788	. . . . . 6 ⊢ (𝑥 = {𝑧 ∈ {∅, {∅}} ∣ 𝜑} → ((𝑥 ⊆ 𝑦 ∨ 𝑦 ⊆ 𝑥) ↔ ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ 𝑦 ∨ 𝑦 ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑})))
10		sseq2 3171	. . . . . . 7 ⊢ (𝑦 = {∅} → ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ 𝑦 ↔ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅}))
11		sseq1 3170	. . . . . . 7 ⊢ (𝑦 = {∅} → (𝑦 ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}))
12	10, 11	orbi12d 788	. . . . . 6 ⊢ (𝑦 = {∅} → (({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ 𝑦 ∨ 𝑦 ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}) ↔ ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∨ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑})))
13	9, 12	rspc2va 2848	. . . . 5 ⊢ ((({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ∈ On ∧ {∅} ∈ On) ∧ ∀𝑥 ∈ On ∀𝑦 ∈ On (𝑥 ⊆ 𝑦 ∨ 𝑦 ⊆ 𝑥)) → ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∨ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}))
14	2, 6, 13	mpanl12 434	. . . 4 ⊢ (∀𝑥 ∈ On ∀𝑦 ∈ On (𝑥 ⊆ 𝑦 ∨ 𝑦 ⊆ 𝑥) → ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∨ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}))
15	1, 14	ax-mp 5	. . 3 ⊢ ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∨ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑})
16		elirr 4525	. . . . 5 ⊢ ¬ {∅} ∈ {∅}
17		simpl 108	. . . . . . 7 ⊢ (({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∧ 𝜑) → {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅})
18		simpr 109	. . . . . . . 8 ⊢ (({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∧ 𝜑) → 𝜑)
19		p0ex 4174	. . . . . . . . . 10 ⊢ {∅} ∈ V
20	19	prid2 3690	. . . . . . . . 9 ⊢ {∅} ∈ {∅, {∅}}
21		biidd 171	. . . . . . . . . 10 ⊢ (𝑧 = {∅} → (𝜑 ↔ 𝜑))
22	21	elrab3 2887	. . . . . . . . 9 ⊢ ({∅} ∈ {∅, {∅}} → ({∅} ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ 𝜑))
23	20, 22	ax-mp 5	. . . . . . . 8 ⊢ ({∅} ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ 𝜑)
24	18, 23	sylibr 133	. . . . . . 7 ⊢ (({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∧ 𝜑) → {∅} ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑})
25	17, 24	sseldd 3148	. . . . . 6 ⊢ (({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∧ 𝜑) → {∅} ∈ {∅})
26	25	ex 114	. . . . 5 ⊢ ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} → (𝜑 → {∅} ∈ {∅}))
27	16, 26	mtoi 659	. . . 4 ⊢ ({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} → ¬ 𝜑)
28		snssg 3716	. . . . . 6 ⊢ (∅ ∈ On → (∅ ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}))
29	4, 28	ax-mp 5	. . . . 5 ⊢ (∅ ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑})
30		0ex 4116	. . . . . . . 8 ⊢ ∅ ∈ V
31	30	prid1 3689	. . . . . . 7 ⊢ ∅ ∈ {∅, {∅}}
32		biidd 171	. . . . . . . 8 ⊢ (𝑧 = ∅ → (𝜑 ↔ 𝜑))
33	32	elrab3 2887	. . . . . . 7 ⊢ (∅ ∈ {∅, {∅}} → (∅ ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ 𝜑))
34	31, 33	ax-mp 5	. . . . . 6 ⊢ (∅ ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} ↔ 𝜑)
35	34	biimpi 119	. . . . 5 ⊢ (∅ ∈ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} → 𝜑)
36	29, 35	sylbir 134	. . . 4 ⊢ ({∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑} → 𝜑)
37	27, 36	orim12i 754	. . 3 ⊢ (({𝑧 ∈ {∅, {∅}} ∣ 𝜑} ⊆ {∅} ∨ {∅} ⊆ {𝑧 ∈ {∅, {∅}} ∣ 𝜑}) → (¬ 𝜑 ∨ 𝜑))
38	15, 37	ax-mp 5	. 2 ⊢ (¬ 𝜑 ∨ 𝜑)
39		orcom 723	. 2 ⊢ ((¬ 𝜑 ∨ 𝜑) ↔ (𝜑 ∨ ¬ 𝜑))
40	38, 39	mpbi 144	1 ⊢ (𝜑 ∨ ¬ 𝜑)

Syntax hints:  ¬ wn 3   ∧ wa 103   ↔ wb 104   ∨ wo 703   = wceq 1348   ∈ wcel 2141  ∀wral 2448  {crab 2452   ⊆ wss 3121  ∅c0 3414  {csn 3583  {cpr 3584  Oncon0 4348  suc csuc 4350

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-13 2143  ax-14 2144  ax-ext 2152  ax-sep 4107  ax-nul 4115  ax-pow 4160  ax-pr 4194  ax-un 4418  ax-setind 4521

This theorem depends on definitions:  df-bi 116  df-3an 975  df-tru 1351  df-nf 1454  df-sb 1756  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ne 2341  df-ral 2453  df-rex 2454  df-rab 2457  df-v 2732  df-dif 3123  df-un 3125  df-in 3127  df-ss 3134  df-nul 3415  df-pw 3568  df-sn 3589  df-pr 3590  df-uni 3797  df-tr 4088  df-iord 4351  df-on 4353  df-suc 4356

This theorem is referenced by:  onintexmid  4557