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<span class="kw">let </span><font color="Maroon" title="c1">p</font>, <font color="Maroon" title="c2">q</font> be   <a href="xboolean.html#V1" title="XBOOLEAN:attr.1">boolean</a>   <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c1">p</font> <a href="xboolean.html#K8" title="XBOOLEAN:func.8">'nand'</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">p</font> <a href="xboolean.html#K6" title="XBOOLEAN:func.6">=&gt;</a> <font color="Maroon" title="c2">q</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboolean.html#K3" title="XBOOLEAN:func.3">'not'</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">p</font> <a href="xboolean.html#K4" title="XBOOLEAN:func.4">'&amp;'</a> <font color="Maroon" title="c2">q</font></span>)</span></span><br/>



<a NAME="E1:65"/>
( <font color="Maroon" title="c1">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboolean.html#K1" title="XBOOLEAN:func.1">FALSE</a>  or <font color="Maroon" title="c1">p</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboolean.html#K2" title="XBOOLEAN:func.2">TRUE</a>  )
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="xboolean.html#D3" target="_self" onmouseover="rs('xboolean/D3')" onmouseout="rh()">Def3</a></span>;<br/>
<span class="kw">hence </span><a NAME="E2:65"/>
<font color="Maroon" title="c1">p</font> <a href="xboolean.html#K8" title="XBOOLEAN:func.8">'nand'</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">p</font> <a href="xboolean.html#K6" title="XBOOLEAN:func.6">=&gt;</a> <font color="Maroon" title="c2">q</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboolean.html#K3" title="XBOOLEAN:func.3">'not'</a> <span class="p1">(<span class="default"><font color="Maroon" title="c1">p</font> <a href="xboolean.html#K4" title="XBOOLEAN:func.4">'&amp;'</a> <font color="Maroon" title="c2">q</font></span>)</span>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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