<?xml version="1.0"?>
<div class="add">

<b>let </b><font color="Maroon">L</font> be   <a href="lattices.html#NM1">Lattice</a>;<br/><b>let </b><font color="Maroon">F</font> be    <a href="filter_0.html#M1">Filter</a> of <font color="Maroon">L</font>;<br/>



<a NAME="E1:16"/>
for <font color="Olive">p</font>, <font color="Olive">q</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L</font>  st <font color="Olive">p</font> <a href="hidden.html#R2">in</a> <font color="Maroon">F</font> &amp; <font color="Olive">q</font> <a href="hidden.html#R2">in</a> <font color="Maroon">F</font> holds <br/>( <font color="Olive">p</font> <a href="lattices.html#K4">"/\"</a> <font color="Olive">q</font> <a href="hidden.html#R2">in</a> <font color="Maroon">F</font> &amp; <font color="Olive">p</font> <a href="lattices.html#K3">"\/"</a> <font color="Olive">q</font> <a href="hidden.html#R2">in</a> <font color="Maroon">F</font> )
 
<b>by </b><i><a class="ref" href="filter_0.html#T10">FILTER_0:10</a>, <a class="ref" href="filter_0.html#D1">FILTER_0:def 1</a></i>;<br/>
<b>hence </b><a NAME="E2:16"/>
<font color="Maroon">F</font> is    <a href="lattice4.html#M2" target="_self">ClosedSubset</a> of <font color="Maroon">L</font>
 <b>by </b><i/>;<br/>


</div>
