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<b>let </b><font color="Maroon" title="c1">L</font> be   <a href="robbins1.html#NM1" title="ROBBINS1:NM.1">preOrthoLattice</a>; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> ( <font color="Maroon" title="c1">L</font> is <a href="robbins2.html#V2" title="ROBBINS2:attr.2">satisfying_MD_1</a> &amp; <font color="Maroon" title="c1">L</font> is <a href="robbins2.html#V3" title="ROBBINS2:attr.3">satisfying_MD_2</a> &amp; <font color="Maroon" title="c1">L</font> is <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a> implies <font color="Maroon" title="c1">L</font> is <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a> )</span><br/>

<b>assume </b><a NAME="E1:68_1_1"/>
( <font color="Maroon" title="c1">L</font> is <a href="robbins2.html#V2" title="ROBBINS2:attr.2">satisfying_MD_1</a> &amp; <font color="Maroon" title="c1">L</font> is <a href="robbins2.html#V3" title="ROBBINS2:attr.3">satisfying_MD_2</a> &amp; <font color="Maroon" title="c1">L</font> is <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a> )
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> <font color="Maroon" title="c1">L</font> is <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a></span><br/>

<b>then reconsider </b><font color="Maroon" title="c2">L'</font> = <font color="Maroon" title="c1">L</font> as  <a href="robbins1.html#V9" title="ROBBINS1:attr.9">de_Morgan</a> <a href="robbins2.html#V2" title="ROBBINS2:attr.2">satisfying_MD_1</a> <a href="robbins2.html#V3" title="ROBBINS2:attr.3">satisfying_MD_2</a> <a href="robbins1.html#NM1" title="ROBBINS1:NM.1">preOrthoLattice</a> ;<br/>
<a NAME="E3:68_1_1"/>
<font color="Maroon" title="c2">L'</font> is <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a>
 
;<br/>
<b>hence </b><a NAME="E4:68_1_1"/>
<font color="Maroon" title="c1">L</font> is <a href="lattices.html#V17" title="LATTICES:attr.17">Boolean</a>
 ; <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> verum</span><br/>


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