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

<b>reconsider </b><font color="Maroon">c<sub>2</sub></font> = <a href="qc_lang1.html#K5">QC-pred_symbols</a>  <a href="margrel1.html#K1">--&gt;</a> <span class="p1">(<span class="default"><a href="margrel1.html#K4">empty_rel</a> <font color="Maroon">c<sub>1</sub></font></span>)</span> as   <a href="funct_2.html#NM1">Function</a> of  <a href="qc_lang1.html#K5">QC-pred_symbols</a> , <a href="margrel1.html#K3">relations_on</a> <font color="Maroon">c<sub>1</sub></font> ;<br/>
<b>take </b>
<font color="Maroon">c<sub>2</sub></font>
;<br/>

<b>let </b><font color="Maroon">c<sub>3</sub></font> be    <a href="subset_1.html#M1">Element</a> of  <a href="qc_lang1.html#K5">QC-pred_symbols</a> ;<br/>

<b>thus </b><a NAME="E2:19_1_1"/>
for <font color="Olive">b<sub>1</sub></font> being   <a href="subset_1.html#M1">Element</a> of  <a href="margrel1.html#K3">relations_on</a> <font color="Maroon">c<sub>1</sub></font> holds <br/>(  not <font color="Maroon">c<sub>2</sub></font> <a href="funct_2.html#K3">.</a> <font color="Maroon">c<sub>3</sub></font> <a href="margrel1.html#R1">=</a> <font color="Olive">b<sub>1</sub></font> or <font color="Olive">b<sub>1</sub></font> <a href="margrel1.html#R1">=</a>  <a href="margrel1.html#K4">empty_rel</a> <font color="Maroon">c<sub>1</sub></font> or  <a href="qc_lang1.html#K6">the_arity_of</a> <font color="Maroon">c<sub>3</sub></font> <a href="hidden.html#R1">=</a>  <a href="margrel1.html#K5">the_arity_of</a> <font color="Olive">b<sub>1</sub></font> )
 <b>by </b><i><a class="ref" href="funcop_1.html#T13">FUNCOP_1:13</a></i>;<br/>


</div>
