Theorem posasymb 18486

Description: A poset ordering is asymmetric. (Contributed by NM, 21-Oct-2011.)

Hypotheses

Ref	Expression
posi.b	⊢ 𝐵 = (Base‘𝐾)
posi.l	⊢ ≤ = (le‘𝐾)

Assertion

Ref	Expression
posasymb	⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) ↔ 𝑋 = 𝑌))

Proof of Theorem posasymb

Step	Hyp	Ref	Expression
1		simp1 1154	. . . 4 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → 𝐾 ∈ Poset)
2		simp2 1155	. . . 4 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → 𝑋 ∈ 𝐵)
3		simp3 1156	. . . 4 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → 𝑌 ∈ 𝐵)
4		posi.b	. . . . 5 ⊢ 𝐵 = (Base‘𝐾)
5		posi.l	. . . . 5 ⊢ ≤ = (le‘𝐾)
6	4, 5	posi 18484	. . . 4 ⊢ ((𝐾 ∈ Poset ∧ (𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵)) → (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑌) → 𝑋 ≤ 𝑌)))
7	1, 2, 3, 3, 6	syl13anc 1399	. . 3 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → (𝑋 ≤ 𝑋 ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌) ∧ ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑌) → 𝑋 ≤ 𝑌)))
8	7	simp2d 1161	. 2 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) → 𝑋 = 𝑌))
9	4, 5	posref 18485	. . . . 5 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵) → 𝑋 ≤ 𝑋)
10		breq2 5107	. . . . 5 ⊢ (𝑋 = 𝑌 → (𝑋 ≤ 𝑋 ↔ 𝑋 ≤ 𝑌))
11	9, 10	syl5ibcom 248	. . . 4 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵) → (𝑋 = 𝑌 → 𝑋 ≤ 𝑌))
12		breq1 5106	. . . . 5 ⊢ (𝑋 = 𝑌 → (𝑋 ≤ 𝑋 ↔ 𝑌 ≤ 𝑋))
13	9, 12	syl5ibcom 248	. . . 4 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵) → (𝑋 = 𝑌 → 𝑌 ≤ 𝑋))
14	11, 13	jcad 522	. . 3 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵) → (𝑋 = 𝑌 → (𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋)))
15	14	3adant3 1150	. 2 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → (𝑋 = 𝑌 → (𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋)))
16	8, 15	impbid 215	1 ⊢ ((𝐾 ∈ Poset ∧ 𝑋 ∈ 𝐵 ∧ 𝑌 ∈ 𝐵) → ((𝑋 ≤ 𝑌 ∧ 𝑌 ≤ 𝑋) ↔ 𝑋 = 𝑌))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   ∧ w3a 1103   = wceq 1570   ∈ wcel 2145   class class class wbr 5103  ‘cfv 6537  Basecbs 17380  lecple 17428  Posetcpo 18474

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-ext 2733  ax-nul 5260

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-sb 2100  df-clab 2740  df-cleq 2753  df-clel 2836  df-ne 2957  df-ral 3078  df-rex 3088  df-rab 3414  df-v 3453  df-sbc 3740  df-dif 3902  df-un 3904  df-ss 3916  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-iota 6493  df-fv 6545  df-proset 18461  df-poset 18480

This theorem is used by:  odupos  18493  pltnle  18503  pltval3  18504  lublecllem  18525  poslubmo  18576  posglbmo  18577  latasymb  18609  latleeqj1  18618  latleeqm1  18634  posrasymb  33521  mgcf1olem1  33555  mgcf1olem2  33556  archirngz  33743  archiabllem1a  33745  ople0  40224  op1le  40229  atlle0  40342