Theorem isposi 18369

Description: Properties that determine a poset (implicit structure version). (Contributed by NM, 11-Sep-2011.)

Hypotheses

Ref	Expression
isposi.k	⊢ 𝐾 ∈ V
isposi.b	⊢ 𝐵 = (Base‘𝐾)
isposi.l	⊢ ≤ = (le‘𝐾)
isposi.1	⊢ (𝑥 ∈ 𝐵 → 𝑥 ≤ 𝑥)
isposi.2	⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦))
isposi.3	⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐵) → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧))

Assertion

Ref	Expression
isposi	⊢ 𝐾 ∈ Poset

Distinct variable groups:   𝑥,𝑦,𝑧,𝐵   𝑥, ≤ ,𝑦,𝑧

Allowed substitution hints:   𝐾(𝑥,𝑦,𝑧)

Proof of Theorem isposi

Step	Hyp	Ref	Expression
1		isposi.k	. 2 ⊢ 𝐾 ∈ V
2		isposi.1	. . . . 5 ⊢ (𝑥 ∈ 𝐵 → 𝑥 ≤ 𝑥)
3	2	3ad2ant1 1134	. . . 4 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐵) → 𝑥 ≤ 𝑥)
4		isposi.2	. . . . 5 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦))
5	4	3adant3 1133	. . . 4 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐵) → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦))
6		isposi.3	. . . 4 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐵) → ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧))
7	3, 5, 6	3jca 1129	. . 3 ⊢ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐵) → (𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧)))
8	7	rgen3 3204	. 2 ⊢ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧))
9		isposi.b	. . 3 ⊢ 𝐵 = (Base‘𝐾)
10		isposi.l	. . 3 ⊢ ≤ = (le‘𝐾)
11	9, 10	ispos 18360	. 2 ⊢ (𝐾 ∈ Poset ↔ (𝐾 ∈ V ∧ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐵 (𝑥 ≤ 𝑥 ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑥) → 𝑥 = 𝑦) ∧ ((𝑥 ≤ 𝑦 ∧ 𝑦 ≤ 𝑧) → 𝑥 ≤ 𝑧))))
12	1, 8, 11	mpbir2an 711	1 ⊢ 𝐾 ∈ Poset

Syntax hints:   → wi 4   ∧ wa 395   ∧ w3a 1087   = wceq 1540   ∈ wcel 2108  ∀wral 3061  Vcvv 3480   class class class wbr 5143  ‘cfv 6561  Basecbs 17247  lecple 17304  Posetcpo 18353

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-ext 2708  ax-nul 5306

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2065  df-clab 2715  df-cleq 2729  df-clel 2816  df-ne 2941  df-ral 3062  df-rex 3071  df-rab 3437  df-v 3482  df-dif 3954  df-un 3956  df-ss 3968  df-nul 4334  df-if 4526  df-sn 4627  df-pr 4629  df-op 4633  df-uni 4908  df-br 5144  df-iota 6514  df-fv 6569  df-poset 18359

This theorem is referenced by:  isposix  18370  isposixOLD  18371  xrstos  33012  xrge0omnd  33088