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<b>let </b><font color="Maroon">H</font> be  non <a href="struct_0.html#V3">empty</a> <a href="yellow_0.html#V1">lower-bounded</a>  <a href="orders_2.html#L1">RelStr</a> ;<br/>

<b>assume </b><a NAME="E1:133"/><i><font color="Green">E32</font></i>: 
<font color="Maroon">H</font> <a href="waybel_1.html#NR13" target="_self">is_a_Heyting_algebra</a> 
 ;<br/>

<b>let </b><font color="Maroon">a</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">H</font>, <font color="Maroon">b</font> be   <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">H</font>;<br/>

<a NAME="E2:133"/><i><font color="Green">E35</font></i>: 
<font color="Maroon">H</font> is   <a href="waybel_0.html#NM8">LATTICE</a>
 
<b>by </b><i>, </i>;<br/>
<a NAME="E3:133"/>
( (  <a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">b</font> <a href="lattice3.html#K11">"/\"</a> <font color="Maroon">a</font> implies <font color="Maroon">b</font> <a href="waybel_1.html#K6" target="_self">=&gt;</a> <span class="p1">(<span class="default"><a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font></span>)</span> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">a</font> ) &amp; ( <font color="Maroon">b</font> <a href="waybel_1.html#K6" target="_self">=&gt;</a> <span class="p1">(<span class="default"><a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font></span>)</span> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">a</font> implies  <a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">b</font> <a href="lattice3.html#K11">"/\"</a> <font color="Maroon">a</font> ) &amp; (  <a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">a</font> <a href="lattice3.html#K11">"/\"</a> <font color="Maroon">b</font> implies <font color="Maroon">a</font> <a href="waybel_1.html#K6" target="_self">=&gt;</a> <span class="p1">(<span class="default"><a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font></span>)</span> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">b</font> ) &amp; ( <font color="Maroon">a</font> <a href="waybel_1.html#K6" target="_self">=&gt;</a> <span class="p1">(<span class="default"><a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font></span>)</span> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">b</font> implies  <a href="yellow_0.html#K3">Bottom</a> <font color="Maroon">H</font> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">a</font> <a href="lattice3.html#K11">"/\"</a> <font color="Maroon">b</font> ) )
 
<b>by </b><i>, </i>;<br/>
<b>hence </b><a NAME="E4:133"/>
(  <a href="waybel_1.html#K7" target="_self">'not'</a> <font color="Maroon">a</font> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">b</font> iff  <a href="waybel_1.html#K7" target="_self">'not'</a> <font color="Maroon">b</font> <a href="orders_2.html#NR2" target="_self">&gt;=</a> <font color="Maroon">a</font> )
 <b>by </b><i><a class="ref" href="waybel_1.html#D11" target="_self">Def11</a>, <a class="ref" href="lattice3.html#T15">LATTICE3:15</a></i>;<br/>


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