Theorem wl-mo3t 34343

Description: Closed form of mo3 2604. (Contributed by Wolf Lammen, 18-Aug-2019.)

Assertion

Ref	Expression
wl-mo3t	⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃*𝑥𝜑 ↔ ∀𝑥∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦)))

Distinct variable group:   𝑥,𝑦

Allowed substitution hints:   𝜑(𝑥,𝑦)

Proof of Theorem wl-mo3t

Dummy variable 𝑢 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		nfa1 2121	. . 3 ⊢ Ⅎ𝑥∀𝑥Ⅎ𝑦𝜑
2		nfmo1 2597	. . 3 ⊢ Ⅎ𝑥∃*𝑥𝜑
3		nfnf1 2124	. . . . . . 7 ⊢ Ⅎ𝑦Ⅎ𝑦𝜑
4	3	nfal 2305	. . . . . 6 ⊢ Ⅎ𝑦∀𝑥Ⅎ𝑦𝜑
5		sp 2146	. . . . . . 7 ⊢ (∀𝑥Ⅎ𝑦𝜑 → Ⅎ𝑦𝜑)
6	1, 5	nfmod 2601	. . . . . 6 ⊢ (∀𝑥Ⅎ𝑦𝜑 → Ⅎ𝑦∃*𝑥𝜑)
7	4, 6	nfan1 2165	. . . . 5 ⊢ Ⅎ𝑦(∀𝑥Ⅎ𝑦𝜑 ∧ ∃*𝑥𝜑)
8		df-mo 2576	. . . . . . 7 ⊢ (∃*𝑥𝜑 ↔ ∃𝑢∀𝑥(𝜑 → 𝑥 = 𝑢))
9		sp 2146	. . . . . . . . . 10 ⊢ (∀𝑥(𝜑 → 𝑥 = 𝑢) → (𝜑 → 𝑥 = 𝑢))
10		spsbim 2050	. . . . . . . . . . 11 ⊢ (∀𝑥(𝜑 → 𝑥 = 𝑢) → ([𝑦 / 𝑥]𝜑 → [𝑦 / 𝑥]𝑥 = 𝑢))
11		equsb3 2076	. . . . . . . . . . 11 ⊢ ([𝑦 / 𝑥]𝑥 = 𝑢 ↔ 𝑦 = 𝑢)
12	10, 11	syl6ib 252	. . . . . . . . . 10 ⊢ (∀𝑥(𝜑 → 𝑥 = 𝑢) → ([𝑦 / 𝑥]𝜑 → 𝑦 = 𝑢))
13	9, 12	anim12d 608	. . . . . . . . 9 ⊢ (∀𝑥(𝜑 → 𝑥 = 𝑢) → ((𝜑 ∧ [𝑦 / 𝑥]𝜑) → (𝑥 = 𝑢 ∧ 𝑦 = 𝑢)))
14		equtr2 2011	. . . . . . . . 9 ⊢ ((𝑥 = 𝑢 ∧ 𝑦 = 𝑢) → 𝑥 = 𝑦)
15	13, 14	syl6 35	. . . . . . . 8 ⊢ (∀𝑥(𝜑 → 𝑥 = 𝑢) → ((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦))
16	15	exlimiv 1908	. . . . . . 7 ⊢ (∃𝑢∀𝑥(𝜑 → 𝑥 = 𝑢) → ((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦))
17	8, 16	sylbi 218	. . . . . 6 ⊢ (∃*𝑥𝜑 → ((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦))
18	17	adantl 482	. . . . 5 ⊢ ((∀𝑥Ⅎ𝑦𝜑 ∧ ∃*𝑥𝜑) → ((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦))
19	7, 18	alrimi 2178	. . . 4 ⊢ ((∀𝑥Ⅎ𝑦𝜑 ∧ ∃*𝑥𝜑) → ∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦))
20	19	ex 413	. . 3 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃*𝑥𝜑 → ∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦)))
21	1, 2, 20	alrimd 2180	. 2 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃*𝑥𝜑 → ∀𝑥∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦)))
22		nfa1 2121	. . . . . 6 ⊢ Ⅎ𝑥∀𝑥((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦)
23		nfs1v 2237	. . . . . 6 ⊢ Ⅎ𝑥[𝑦 / 𝑥]𝜑
24		pm3.3 449	. . . . . . . 8 ⊢ (((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → (𝜑 → ([𝑦 / 𝑥]𝜑 → 𝑥 = 𝑦)))
25	24	com23 86	. . . . . . 7 ⊢ (((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → ([𝑦 / 𝑥]𝜑 → (𝜑 → 𝑥 = 𝑦)))
26	25	sps 2148	. . . . . 6 ⊢ (∀𝑥((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → ([𝑦 / 𝑥]𝜑 → (𝜑 → 𝑥 = 𝑦)))
27	22, 23, 26	alrimd 2180	. . . . 5 ⊢ (∀𝑥((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → ([𝑦 / 𝑥]𝜑 → ∀𝑥(𝜑 → 𝑥 = 𝑦)))
28	27	aleximi 1813	. . . 4 ⊢ (∀𝑦∀𝑥((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → (∃𝑦[𝑦 / 𝑥]𝜑 → ∃𝑦∀𝑥(𝜑 → 𝑥 = 𝑦)))
29	28	alcoms 2127	. . 3 ⊢ (∀𝑥∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → (∃𝑦[𝑦 / 𝑥]𝜑 → ∃𝑦∀𝑥(𝜑 → 𝑥 = 𝑦)))
30		moabs 2579	. . . 4 ⊢ (∃*𝑥𝜑 ↔ (∃𝑥𝜑 → ∃*𝑥𝜑))
31		wl-sb8et 34320	. . . . 5 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃𝑥𝜑 ↔ ∃𝑦[𝑦 / 𝑥]𝜑))
32		wl-mo2t 34342	. . . . 5 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃*𝑥𝜑 ↔ ∃𝑦∀𝑥(𝜑 → 𝑥 = 𝑦)))
33	31, 32	imbi12d 346	. . . 4 ⊢ (∀𝑥Ⅎ𝑦𝜑 → ((∃𝑥𝜑 → ∃*𝑥𝜑) ↔ (∃𝑦[𝑦 / 𝑥]𝜑 → ∃𝑦∀𝑥(𝜑 → 𝑥 = 𝑦))))
34	30, 33	syl5bb 284	. . 3 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃*𝑥𝜑 ↔ (∃𝑦[𝑦 / 𝑥]𝜑 → ∃𝑦∀𝑥(𝜑 → 𝑥 = 𝑦))))
35	29, 34	syl5ibr 247	. 2 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∀𝑥∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦) → ∃*𝑥𝜑))
36	21, 35	impbid 213	1 ⊢ (∀𝑥Ⅎ𝑦𝜑 → (∃*𝑥𝜑 ↔ ∀𝑥∀𝑦((𝜑 ∧ [𝑦 / 𝑥]𝜑) → 𝑥 = 𝑦)))

Syntax hints:   → wi 4   ↔ wb 207   ∧ wa 396  ∀wal 1520  ∃wex 1761  Ⅎwnf 1765  [wsb 2042  ∃*wmo 2574

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1777  ax-4 1791  ax-5 1888  ax-6 1947  ax-7 1992  ax-10 2112  ax-11 2126  ax-12 2141  ax-13 2344

This theorem depends on definitions:  df-bi 208  df-an 397  df-or 843  df-tru 1525  df-ex 1762  df-nf 1766  df-sb 2043  df-mo 2576

This theorem is referenced by: (None)