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<b>let </b><font color="Maroon" title="c1">S</font> be    <a href="msualg_1.html#L1" title="MSUALG_1:struct.1">ManySortedSign</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">S</font> is <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a> &amp; <font color="Maroon" title="c1">S</font> is <a href="instalg1.html#V1" title="INSTALG1:attr.1">feasible</a> implies <font color="Maroon" title="c1">S</font> is <a href="struct_0.html#V11" title="STRUCT_0:attr.11">void</a> )</span><br/>

<b>assume </b><a NAME="E1:9_3_1"/><i><font color="Green" title="E7">A1</font></i>: 
the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Maroon" title="c1">S</font> is <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="struct_0.html#D1" title="STRUCT_0:def.1">STRUCT_0:def 1</a> <a class="txt" onclick="hs(this)" href="javascript:()"><i><font color="Red">::  thesis: </font></i></a><span class="hide"> (  not <font color="Maroon" title="c1">S</font> is <a href="instalg1.html#V1" title="INSTALG1:attr.1">feasible</a> or <font color="Maroon" title="c1">S</font> is <a href="struct_0.html#V11" title="STRUCT_0:attr.11">void</a> )</span><br/>

<b>assume </b><a NAME="E2:9_3_1"/>
( the <a href="struct_0.html#U1" title="STRUCT_0:sel.1">carrier</a> of <font color="Maroon" title="c1">S</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  implies the <a href="struct_0.html#U4" title="STRUCT_0:sel.4">carrier'</a> of <font color="Maroon" title="c1">S</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  )
 ; <i><font color="Red">:: according to </font></i><a class="ref" href="instalg1.html#D1" target="_self" title="INSTALG1:def.1">INSTALG1:def 1</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">S</font> is <a href="struct_0.html#V11" title="STRUCT_0:attr.11">void</a></span><br/>

<b>hence </b><a NAME="E3:9_3_1"/>
<font color="Maroon" title="c1">S</font> is <a href="struct_0.html#V11" title="STRUCT_0:attr.11">void</a>
 <b>by </b><i><a class="txt" href="#E1:9_3_1"><i><font color="Green" title="E7">A1</font></i></a></i>; <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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