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<b>let </b><font color="Maroon" title="c1">C</font> be   <a href="cat_1.html#NM4" title="CAT_1:NM.4">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>assume </b><a NAME="E1:69"/>
<font color="Maroon" title="c2">a</font> is <a href="cat_1.html#V7" title="CAT_1:attr.7">initial</a>
 ;<br/>

<b>then consider </b><font color="Maroon" title="c3">f</font> being    <a href="cat_1.html#M1" title="CAT_1:mode.1">Morphism</a> of <font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c2">a</font><b> such that </b><br/><a NAME="E3:69"/><i><font color="Green" title="E43">A1</font></i>: 
for <font color="Olive" title="b1">g</font> being   <a href="cat_1.html#M1" title="CAT_1:mode.1">Morphism</a> of <font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c2">a</font> holds  <font color="Maroon" title="c3">f</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Olive" title="b1">g</font>
 <b>by </b><i><a class="ref" href="cat_1.html#D16" target="_self" title="CAT_1:def.16">Def16</a></i>;<br/>
<b>let </b><font color="Maroon" title="c4">h</font> be    <a href="cat_1.html#M1" title="CAT_1:mode.1">Morphism</a> of <font color="Maroon" title="c2">a</font>,<font color="Maroon" title="c2">a</font>;<br/>

<a NAME="E4:69"/>
 <a href="cat_1.html#K10" title="CAT_1:func.10">id</a> <font color="Maroon" title="c2">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c3">f</font>
 
<b>by </b><i><a class="txt" href="cat_1.html#E3:69"><i><font color="Green" title="E43">A1</font></i></a></i>;<br/>
<b>hence </b><a NAME="E5:69"/>
 <a href="cat_1.html#K10" title="CAT_1:func.10">id</a> <font color="Maroon" title="c2">a</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c4">h</font>
 <b>by </b><i><a class="txt" href="cat_1.html#E3:69"><i><font color="Green" title="E43">A1</font></i></a></i>;<br/>


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