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<span class="kw">let </span><font color="Maroon" title="c1">Y</font>, <font color="Maroon" title="c2">X</font>, <font color="Maroon" title="c3">Z</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">set</a> ; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c1">Y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> &amp; <font color="Maroon" title="c3">Z</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c1">Y</font> implies <font color="Maroon" title="c3">Z</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> )</span><br/>





<a NAME="E1:8"/>
 <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> <a href="classes1.html#R1" title="CLASSES1:pred.1">is_Tarski-Class_of</a> <font color="Maroon" title="c2">X</font>
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="classes1.html#D4" target="_self" title="CLASSES1:def.4">Def4</a></span>;<br/>
<a NAME="E2:8"/><span class="kw">then </span>
 <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> is  <a href="classes1.html#V2" title="CLASSES1:attr.2">Tarski</a> 
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="classes1.html#D3" target="_self" title="CLASSES1:def.3">Def3</a></span>;<br/>
<a NAME="E3:8"/><span class="kw">then </span>
 <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> is  <a href="classes1.html#V1" title="CLASSES1:attr.1">subset-closed</a> 
 
<span class="kw">by</span> <span class="lab"><a class="ref" href="classes1.html#D2" target="_self" title="CLASSES1:def.2">Def2</a></span>;<br/>
<span class="kw">hence </span><a NAME="E4:8"/>
( <font color="Maroon" title="c1">Y</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> &amp; <font color="Maroon" title="c3">Z</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c1">Y</font> implies <font color="Maroon" title="c3">Z</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="classes1.html#K1" title="CLASSES1:func.1">Tarski-Class</a> <font color="Maroon" title="c2">X</font> )
 <span class="kw">by</span> <span class="lab"><a class="ref" href="classes1.html#D1" target="_self" title="CLASSES1:def.1">Def1</a></span>; <a class="txt" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


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