Limit Inferior of Inclusion Net is Supremum of Directed Subset

Theorem
Let $L = \left({S, \vee, \wedge, \preceq}\right)$ be an up-complete lattice.

Let $D \subseteq S$ be a directed subset of $S$.

Let $\left({D, \preceq'}\right)$ be a directed ordered subset of $L$.

Let $i_D: D \to S$, the inclusion mapping, be a Moore-Smith sequence in $S$.

Then $\liminf i_D = \sup D$

Proof
We will prove that
 * $\forall j \in D: \inf_L\left({\preceq'\left({j}\right)}\right) = j$

Let $j \in D$.

By definitions of image of element and upper closure of element:
 * $\preceq'\left({j}\right) = j^{\succeq'}$

By Upper Closure in Ordered Subset is Intersection of Subset and Upper Closure:
 * $j^{\succeq'} = D \cap j^\succeq$

By Intersection is Subset:
 * $j^{\succeq'} \subseteq j^\succeq$

By Infimum of Subset and Infimum of Upper Closure of Element:
 * $j \preceq \inf_L\left({\preceq'\left({j}\right)}\right)$

By definition of reflexivity:
 * $j \preceq' j$

By definition

Thus