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<b>let </b><font color="Maroon" title="c2">M</font>, <font color="Maroon" title="c3">N</font> be   <a href="card_1.html#NM1" title="CARD_1:NM.1">Cardinal</a>;<br/>



<b>assume </b><a NAME="E1:28"/><i><font color="Green" title="E20">A1</font></i>: 
not <font color="Maroon" title="c2">M</font> is <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a>
 ;<br/>

<a NAME="E2:28"/>
<font color="Maroon" title="c2">M</font>,<font color="Maroon" title="c3">N</font> <a href="xboole_0.html#R3" title="XBOOLE_0:pred.3">are_c=-comparable</a> 
 
<b>by </b><i><a class="ref" href="ordinal1.html#T25" title="ORDINAL1:th.25">ORDINAL1:25</a></i>;<br/>
<a NAME="E3:28"/><b>then </b>
( <font color="Maroon" title="c2">M</font> <a href="card_1.html#NR1" title="CARD_1:NR.1">&lt;=`</a> <font color="Maroon" title="c3">N</font> or <font color="Maroon" title="c3">N</font> <a href="card_1.html#NR1" title="CARD_1:NR.1">&lt;=`</a> <font color="Maroon" title="c2">M</font> )
 
<b>by </b><i><a class="ref" href="xboole_0.html#D9" title="XBOOLE_0:def.9">XBOOLE_0:def 9</a></i>;<br/>
<a NAME="E4:28"/><b>then </b>
( ( <font color="Maroon" title="c2">M</font> <a href="card_1.html#NR1" title="CARD_1:NR.1">&lt;=`</a> <font color="Maroon" title="c3">N</font> &amp; not <font color="Maroon" title="c3">N</font> is <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> ) or ( <font color="Maroon" title="c2">M</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c3">N</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">M</font> &amp; <font color="Maroon" title="c3">N</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c2">M</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c2">M</font> ) )
 
<b>by </b><i><a class="txt" href="card_4.html#E1:28"><i><font color="Green" title="E20">A1</font></i></a>, <a class="ref" href="card_4.html#T26" target="_self" title="CARD_4:th.26">Th26</a>, <a class="ref" href="card_4.html#T34" target="_self" title="CARD_4:th.34">Th34</a></i>;<br/>
<b>hence </b><a NAME="E5:28"/>
( not <font color="Maroon" title="c2">M</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c3">N</font> is <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> &amp; not <font color="Maroon" title="c3">N</font> <a href="card_2.html#K1" title="CARD_2:func.1">+`</a> <font color="Maroon" title="c2">M</font> is <a href="finset_1.html#V1" title="FINSET_1:attr.1">finite</a> )
 <b>by </b><i><a class="txt" href="card_4.html#E1:28"><i><font color="Green" title="E20">A1</font></i></a>, <a class="ref" href="card_4.html#T34" target="_self" title="CARD_4:th.34">Th34</a></i>;<br/>


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