<?xml version="1.0"?>
<div class="add">

<b>let </b><font color="Maroon">X</font> be    <a href="hidden.html#M1">set</a> ;<br/><b>let </b><font color="Maroon">A</font> be   <a href="setfam_1.html#NM1">Subset-Family</a> of <font color="Maroon">X</font>;<br/>



<a NAME="E1:13"/>
 <a href="xboole_0.html#K1">{}</a>  is   <a href="setfam_1.html#NM1">Subset-Family</a> of <font color="Maroon">X</font>
 
<b>by </b><i><a class="ref" href="xboole_1.html#T2">XBOOLE_1:2</a></i>;<br/>
<a NAME="E2:13"/><b>then </b>
 <a href="xboole_0.html#K1">{}</a>  is   <a href="setfam_1.html#NM1">Subset-Family</a> of <font color="Maroon">X</font>
 
;<br/>
<b>then consider </b><font color="Maroon">y</font> being   <a href="setfam_1.html#NM1">Subset-Family</a> of <font color="Maroon">X</font><b> such that </b><br/><a NAME="E4:13"/><i><font color="Green">E23</font></i>: 
<font color="Maroon">y</font> <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a> 
 ;<br/>
<a NAME="E5:13"/>
( <font color="Maroon">y</font> <a href="tarski.html#R1">c=</a> <font color="Maroon">A</font> &amp; <font color="Maroon">y</font> is <a href="finset_1.html#V1">finite</a> &amp;  <a href="setfam_1.html#K8">Intersect</a> <font color="Maroon">y</font> <a href="hidden.html#R1">=</a> <font color="Maroon">X</font> )
 
<b>by </b><i>, <a class="ref" href="setfam_1.html#D10">SETFAM_1:def 10</a>, <a class="ref" href="xboole_1.html#T2">XBOOLE_1:2</a></i>;<br/>
<b>hence </b><a NAME="E6:13"/>
<font color="Maroon">X</font> <a href="hidden.html#R2">in</a>  <a href="cantor_1.html#K2" target="_self">FinMeetCl</a> <font color="Maroon">A</font>
 <b>by </b><i/>;<br/>


</div>
