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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E12">Th19</font></span>: <a NAME="T21"><span class="comment"><font color="firebrick">:: OPPCAT_1:21</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">C</font> being   <a href="cat_1.html#NM4" title="CAT_1:NM.4">Category</a><br/>  for <font color="Olive" title="b2">a</font> being   <a href="cat_1.html#NM1" title="CAT_1:NM.1">Object</a> of <span class="p1">(<span class="default"><font color="Olive" title="b1">C</font> <a href="oppcat_1.html#K1" title="OPPCAT_1:func.1">opp</a></span>)</span> holds   <a href="oppcat_1.html#K5" title="OPPCAT_1:func.5">opp</a> <span class="p1">(<span class="default"><a href="cat_1.html#K4" title="CAT_1:func.4">id</a> <font color="Olive" title="b2">a</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="cat_1.html#K4" title="CAT_1:func.4">id</a> <span class="p1">(<span class="default"><a href="oppcat_1.html#K3" title="OPPCAT_1:func.3">opp</a> <font color="Olive" title="b2">a</font></span>)</span></div></div>
