Metamath Proof Explorer


Theorem ipobas

Description: Base set of the inclusion poset. (Contributed by Stefan O'Rear, 30-Jan-2015) (Revised by Mario Carneiro, 25-Oct-2015)

Ref Expression
Hypothesis ipoval.i ⊢ I = toInc ⁡ F
Assertion ipobas ⊢ F ∈ V → F = Base I

Proof

Step Hyp Ref Expression
1 ipoval.i ⊢ I = toInc ⁡ F
2 ipostr ⊢ Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ∪ ≤ ndx x y | x y ⊆ F ∧ x ⊆ y oc ⁡ ndx x ∈ F ⟼ ⋃ y ∈ F | y ∩ x = ∅ Struct 1 11
3 baseid ⊢ Base = Slot Base ndx
4 snsspr1 ⊢ Base ndx F ⊆ Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y
5 ssun1 ⊢ Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ⊆ Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ∪ ≤ ndx x y | x y ⊆ F ∧ x ⊆ y oc ⁡ ndx x ∈ F ⟼ ⋃ y ∈ F | y ∩ x = ∅
6 4 5 sstri ⊢ Base ndx F ⊆ Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ∪ ≤ ndx x y | x y ⊆ F ∧ x ⊆ y oc ⁡ ndx x ∈ F ⟼ ⋃ y ∈ F | y ∩ x = ∅
7 2 3 6 strfv ⊢ F ∈ V → F = Base Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ∪ ≤ ndx x y | x y ⊆ F ∧ x ⊆ y oc ⁡ ndx x ∈ F ⟼ ⋃ y ∈ F | y ∩ x = ∅
8 eqid ⊢ x y | x y ⊆ F ∧ x ⊆ y = x y | x y ⊆ F ∧ x ⊆ y
9 1 8 ipoval ⊢ F ∈ V → I = Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ∪ ≤ ndx x y | x y ⊆ F ∧ x ⊆ y oc ⁡ ndx x ∈ F ⟼ ⋃ y ∈ F | y ∩ x = ∅
10 9 fveq2d ⊢ F ∈ V → Base I = Base Base ndx F TopSet ⁡ ndx ordTop ⁡ x y | x y ⊆ F ∧ x ⊆ y ∪ ≤ ndx x y | x y ⊆ F ∧ x ⊆ y oc ⁡ ndx x ∈ F ⟼ ⋃ y ∈ F | y ∩ x = ∅
11 7 10 eqtr4d ⊢ F ∈ V → F = Base I