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<b>let </b><font color="Maroon" title="c1">C</font> be   <a href="cat_4.html#NM1" title="CAT_4:NM.1">Cartesian_category</a>;<br/><b>let </b><font color="Maroon" title="c2">a</font> be   <a href="cat_1.html#NM1" title="CAT_1:NM.1">Object</a> of <font color="Maroon" title="c1">C</font>;<br/>



<b>thus </b><a NAME="E1:44"/>
<font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c2">a</font> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <span class="p1">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span> <a href="cat_1.html#R1" title="CAT_1:pred.1">are_isomorphic</a> 
 <div><a class="txt" onclick="hs2(this)" href="javascript:()" title="44_1"><b>proof </b></a><div class="add">

<b>thus </b><a NAME="E1:44_1"/>
(  <a href="cat_1.html#K7" title="CAT_1:func.7">Hom</a> <font color="Maroon" title="c2">a</font>,<span class="p1">(<span class="default"><font color="Maroon" title="c2">a</font> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <span class="p2">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span></span>)</span> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  &amp;  <a href="cat_1.html#K7" title="CAT_1:func.7">Hom</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">a</font> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <span class="p2">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span></span>)</span>,<font color="Maroon" title="c2">a</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  )
 <b>by </b><i><a class="ref" href="cat_4.html#T21" target="_self" title="CAT_4:th.21">Th21</a>, <a class="ref" href="cat_4.html#T30" target="_self" title="CAT_4:th.30">Th30</a></i>; <i><font color="Red">:: according to </font></i><a class="ref" href="cat_4.html#D2" target="_self" title="CAT_4:def.2">CAT_4:def 2</a><br/>

<b>take </b>
 <a href="cat_4.html#K13" title="CAT_4:func.13">rho'</a> <font color="Maroon" title="c2">a</font>
;<br/>

<b>take </b>
 <a href="cat_4.html#K12" title="CAT_4:func.12">rho</a> <font color="Maroon" title="c2">a</font>
;<br/>

<b>thus </b><a NAME="E2:44_1"/>
( <span class="p1">(<span class="default"><a href="cat_4.html#K13" title="CAT_4:func.13">rho'</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="cat_1.html#K9" title="CAT_1:func.9">*</a> <span class="p1">(<span class="default"><a href="cat_4.html#K12" title="CAT_4:func.12">rho</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="cat_1.html#K10" title="CAT_1:func.10">id</a> <span class="p1">(<span class="default"><font color="Maroon" title="c2">a</font> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <span class="p2">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span></span>)</span> &amp; <span class="p1">(<span class="default"><a href="cat_4.html#K12" title="CAT_4:func.12">rho</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="cat_1.html#K9" title="CAT_1:func.9">*</a> <span class="p1">(<span class="default"><a href="cat_4.html#K13" title="CAT_4:func.13">rho'</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="cat_1.html#K10" title="CAT_1:func.10">id</a> <font color="Maroon" title="c2">a</font> )
 <b>by </b><i><a class="ref" href="cat_4.html#T31" target="_self" title="CAT_4:th.31">Th31</a></i>;<br/>


</div><b>end;</b></div>

<b>thus </b><a NAME="E2:44"/>
(  <a href="cat_1.html#K7" title="CAT_1:func.7">Hom</a> <font color="Maroon" title="c2">a</font>,<span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  &amp;  <a href="cat_1.html#K7" title="CAT_1:func.7">Hom</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <font color="Maroon" title="c2">a</font></span>)</span>,<font color="Maroon" title="c2">a</font> <a href="hidden.html#NR2" title="HIDDEN:NR.2">&lt;&gt;</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  )
 <b>by </b><i><a class="ref" href="cat_4.html#T21" target="_self" title="CAT_4:th.21">Th21</a>, <a class="ref" href="cat_4.html#T30" target="_self" title="CAT_4:th.30">Th30</a></i>; <i><font color="Red">:: according to </font></i><a class="ref" href="cat_4.html#D2" target="_self" title="CAT_4:def.2">CAT_4:def 2</a><br/>

<b>take </b>
 <a href="cat_4.html#K11" title="CAT_4:func.11">lambda'</a> <font color="Maroon" title="c2">a</font>
;<br/>

<b>take </b>
 <a href="cat_4.html#K10" title="CAT_4:func.10">lambda</a> <font color="Maroon" title="c2">a</font>
;<br/>

<b>thus </b><a NAME="E3:44"/>
( <span class="p1">(<span class="default"><a href="cat_4.html#K11" title="CAT_4:func.11">lambda'</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="cat_1.html#K9" title="CAT_1:func.9">*</a> <span class="p1">(<span class="default"><a href="cat_4.html#K10" title="CAT_4:func.10">lambda</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="cat_1.html#K10" title="CAT_1:func.10">id</a> <span class="p1">(<span class="default"><span class="p2">(<span class="default"><a href="cat_4.html#K1" title="CAT_4:func.1">[1]</a> <font color="Maroon" title="c1">C</font></span>)</span> <a href="cat_4.html#K2" title="CAT_4:func.2">[x]</a> <font color="Maroon" title="c2">a</font></span>)</span> &amp; <span class="p1">(<span class="default"><a href="cat_4.html#K10" title="CAT_4:func.10">lambda</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="cat_1.html#K9" title="CAT_1:func.9">*</a> <span class="p1">(<span class="default"><a href="cat_4.html#K11" title="CAT_4:func.11">lambda'</a> <font color="Maroon" title="c2">a</font></span>)</span> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="cat_1.html#K10" title="CAT_1:func.10">id</a> <font color="Maroon" title="c2">a</font> )
 <b>by </b><i><a class="ref" href="cat_4.html#T31" target="_self" title="CAT_4:th.31">Th31</a></i>;<br/>


</div>
