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<div class="add">

<span class="kw">let </span><font color="Maroon" title="c3">G</font> be   <a href="struct_0.html#NM3" title="STRUCT_0:NM.3">Subset-Family</a> of <font color="Maroon" title="c1">P</font>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c3">G</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) iff  for <font color="Olive" title="b1">B1</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font> holds <br/> ( <font color="Olive" title="b1">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Maroon" title="c3">G</font> iff <font color="Olive" title="b1">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  ) )</span><br/>

<span class="kw">set </span><font color="Maroon" title="c4">Om</font> =  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>);<br/>
<a NAME="E1:81_1_1"/>
 for <font color="Olive" title="b1">B1</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font> holds <br/> ( <font color="Olive" title="b1">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) iff <font color="Olive" title="b1">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  )
 
<div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="81_1_1_1"><span class="kw">proof </span></a><div class="add">

<span class="kw">let </span><font color="Maroon" title="c5">B1</font> be   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c5">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) iff <font color="Maroon" title="c5">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  )</span><br/>

<span class="kw">thus </span><a NAME="E1:81_1_1_1"/>
( <font color="Maroon" title="c5">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) implies <font color="Maroon" title="c5">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  )
  <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( <font color="Maroon" title="c5">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  implies <font color="Maroon" title="c5">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) )</span><div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="81_1_1_1_1"><span class="kw">proof </span></a><div class="add">

<span class="kw">assume </span><a NAME="E1:81_1_1_1_1"/>
<font color="Maroon" title="c5">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>)
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a> </span><br/>

<span class="kw">then </span><span class="kw">consider </span><font color="Maroon" title="c6">B2</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font><span class="kw"> such that </span><br/><a NAME="E3:81_1_1_1_1"/><span class="lab"><font color="Green" title="E30">A5</font></span>: 
( <font color="Maroon" title="c6">B2</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">B1</font> &amp; <font color="Maroon" title="c6">B2</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  )
 ;<br/>
<span class="kw">thus </span><a NAME="E4:81_1_1_1_1"/>
<font color="Maroon" title="c5">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a> 
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:81_1_1_1_1"><span class="lab"><font color="Green" title="E30">A5</font></span></a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div><span class="kw">end;</span></div>

<span class="kw">thus </span><a NAME="E2:81_1_1_1"/>
( <font color="Maroon" title="c5">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  implies <font color="Maroon" title="c5">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) )
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div><span class="kw">end;</span></div>
<span class="kw">hence </span><a NAME="E2:81_1_1"/>
( <font color="Maroon" title="c3">G</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) implies  for <font color="Olive" title="b1">B1</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font> holds <br/> ( <font color="Olive" title="b1">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Maroon" title="c3">G</font> iff <font color="Olive" title="b1">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  ) )
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> ( (  for <font color="Olive" title="b1">B1</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font> holds <br/> ( <font color="Olive" title="b1">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Maroon" title="c3">G</font> iff <font color="Olive" title="b1">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  ) ) implies <font color="Maroon" title="c3">G</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) )</span><br/>

<span class="kw">assume </span><a NAME="E3:81_1_1"/><span class="lab"><font color="Green" title="E30">A10</font></span>: 
 for <font color="Olive" title="b1">B1</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font> holds <br/> ( <font color="Olive" title="b1">B1</font> <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Maroon" title="c3">G</font> iff <font color="Olive" title="b1">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  )
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c3">G</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>)</span><br/>

<span class="kw">thus </span><a NAME="E4:81_1_1"/>
<font color="Maroon" title="c3">G</font> <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>)
  <span class="comment"><font color="firebrick">:: according to </font></span><a class="ref" href="xboole_0.html#D10" onmouseover="rs('xboole_0/D10')" onmouseout="rh()">XBOOLE_0:def 10</a> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide">  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) <a href="tarski.html#R1" title="TARSKI:pred.1">c=</a> <font color="Maroon" title="c3">G</font></span><div><a class="txt" onmouseover="tooltip.show('hs2',this)" onmouseout="tooltip.hide()" onclick="hs2(this)" href="javascript:()" title="81_1_1_2"><span class="kw">proof </span></a><div class="add">

<span class="kw">let </span><font color="Maroon" title="c5">a</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <span class="comment"><font color="firebrick">:: according to </font></span><a class="ref" href="tarski.html#D3" onmouseover="rs('tarski/D3')" onmouseout="rh()">TARSKI:def 3</a> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> (  not <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">G</font> or <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) )</span><br/>

<span class="kw">assume </span><a NAME="E1:81_1_1_2"/><span class="lab"><font color="Green" title="E31">A11</font></span>: 
<font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">G</font>
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>)</span><br/>

<span class="kw">then </span><span class="kw">reconsider </span><font color="Maroon" title="c6">B1</font> = <font color="Maroon" title="c5">a</font> as   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font> ;<br/>
<a NAME="E3:81_1_1_2"/>
<font color="Maroon" title="c6">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a> 
 
<span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:81_1_1"><span class="lab"><font color="Green" title="E30">A10</font></span></a>, <a class="txt" href="#E1:81_1_1_2"><span class="lab"><font color="Green" title="E31">A11</font></span></a></span>;<br/>
<span class="kw">hence </span><a NAME="E4:81_1_1_2"/>
<font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>)
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div><span class="kw">end;</span></div>

<span class="kw">let </span><font color="Maroon" title="c5">a</font> be    <a href="hidden.html#M1" title="HIDDEN:mode.1">object</a> ; <span class="comment"><font color="firebrick">:: according to </font></span><a class="ref" href="tarski.html#D3" onmouseover="rs('tarski/D3')" onmouseout="rh()">TARSKI:def 3</a> <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> (  not <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>) or <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">G</font> )</span><br/>

<span class="kw">assume </span><a NAME="E5:81_1_1"/>
<font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a>  <a href="proofs_1.html#K10" title="PROOFS_1:func.10">Omit</a> (<font color="Maroon" title="c1">P</font>,<font color="Maroon" title="c2">B</font>)
 ; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> <font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">G</font></span><br/>

<span class="kw">then </span><span class="kw">consider </span><font color="Maroon" title="c6">B1</font> being   <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <font color="Maroon" title="c1">P</font><span class="kw"> such that </span><br/><a NAME="E7:81_1_1"/><span class="lab"><font color="Green" title="E31">A21</font></span>: 
( <font color="Maroon" title="c6">B1</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a> <font color="Maroon" title="c5">a</font> &amp; <font color="Maroon" title="c6">B1</font> is <font color="Maroon" title="c2">B</font> <a href="proofs_1.html#V13" title="PROOFS_1:attr.13">-omitting</a>  )
 ;<br/>
<span class="kw">thus </span><a NAME="E8:81_1_1"/>
<font color="Maroon" title="c5">a</font> <a href="hidden.html#R2" title="HIDDEN:pred.2">in</a> <font color="Maroon" title="c3">G</font>
 <span class="kw">by</span> <span class="lab"><a class="txt" href="#E3:81_1_1"><span class="lab"><font color="Green" title="E30">A10</font></span></a>, <a class="txt" href="#E7:81_1_1"><span class="lab"><font color="Green" title="E31">A21</font></span></a></span>; <a class="txt" onmouseover="tooltip.show('hs',this)" onmouseout="tooltip.hide()" onclick="hs(this)" href="javascript:()"><span class="comment"><font color="firebrick">::  thesis: </font></span></a><span class="hide"> verum</span><br/>


</div>
