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<b>let </b><font color="Maroon">p</font> be    <a href="subset_1.html#M2">Element</a> of  <a href="cqc_lang.html#K7">CQC-WFF</a> ;<br/>

<b>assume </b><a NAME="E1:58"/><i><font color="Green">E55</font></i>: 
 <a href="qc_lang1.html#K23">still_not-bound_in</a> <font color="Maroon">p</font> <a href="tarski.html#R1">c=</a>  <a href="substut1.html#K9">Bound_Vars</a> <font color="Maroon">p</font>
 ;<br/>

<a NAME="E2:58"/>
 <a href="cqc_lang.html#K10">'not'</a> <font color="Maroon">p</font> is <a href="qc_lang1.html#V3">negative</a>
 
<b>by </b><i><a class="ref" href="qc_lang1.html#D18">QC_LANG1:def 18</a></i>;<br/>
<a NAME="E3:58"/><b>then </b>
 <a href="substut1.html#K9">Bound_Vars</a> <span class="p1">(<span class="default"><a href="cqc_lang.html#K10">'not'</a> <font color="Maroon">p</font></span>)</span> <a href="hidden.html#R1">=</a>  <a href="substut1.html#K9">Bound_Vars</a> <span class="p1">(<span class="default"><a href="qc_lang1.html#K17">the_argument_of</a> <span class="p2">(<span class="default"><a href="cqc_lang.html#K10">'not'</a> <font color="Maroon">p</font></span>)</span></span>)</span>
 
<b>by </b><i><a class="ref" href="substut1.html#T4">SUBSTUT1:4</a></i>;<br/>
<a NAME="E4:58"/><b>then </b>
 <a href="substut1.html#K9">Bound_Vars</a> <span class="p1">(<span class="default"><a href="cqc_lang.html#K10">'not'</a> <font color="Maroon">p</font></span>)</span> <a href="hidden.html#R1">=</a>  <a href="substut1.html#K9">Bound_Vars</a> <font color="Maroon">p</font>
 
<b>by </b><i><a class="ref" href="qc_lang2.html#T2">QC_LANG2:2</a></i>;<br/>
<b>hence </b><a NAME="E5:58"/>
 <a href="qc_lang1.html#K23">still_not-bound_in</a> <span class="p1">(<span class="default"><a href="cqc_lang.html#K10">'not'</a> <font color="Maroon">p</font></span>)</span> <a href="tarski.html#R1">c=</a>  <a href="substut1.html#K9">Bound_Vars</a> <span class="p1">(<span class="default"><a href="cqc_lang.html#K10">'not'</a> <font color="Maroon">p</font></span>)</span>
 <b>by </b><i>, <a class="ref" href="qc_lang3.html#T11">QC_LANG3:11</a></i>;<br/>


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