<?xml version="1.0"?>
<div><span class="kw">theorem </span><a NAME="T33"><span class="comment"><font color="firebrick">:: ORDINAL4:33</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">W</font> being   <a href="classes2.html#NM1" title="CLASSES2:NM.1">Universe</a> holds <br/> (  <a href="ordinal4.html#K2" title="ORDINAL4:func.2">0-element_of</a> <font color="Olive" title="b1">W</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  &amp;  <a href="ordinal4.html#K3" title="ORDINAL4:func.3">1-element_of</a> <font color="Olive" title="b1">W</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> 1 ) ;<br/></div></div>
